So hello everybody, my name is Kyle Freund and on behalf of Lucas, Nico and myself, I'd like to officially welcome you to the IOC 2021. And of course, as many of you know, this builds upon the very successful IOC 2019 in Hungary, and we hope we live up to the standard that was set there. I think this was originally going to be a live conference and we had lots of fun things prepared for you. Various obsidian sources and so forth but I think it's going to work out very well and we have really great program prepared for you. Some topics we're going to cover over the next three days include obsidian sourcing studies and archaeology. So that's divided up regionally so we will have some talks from all over the world. And theoretical methods with another theme of the conference, lithic and technological concerns and theoretical and cultural concerns. Of course, we're going to kick off today with a keynote speaker, Dr. Stephen Shackley and I'm really looking forward to that. I guess I'd like to start by thanking some of our sponsors that have really made this possible. The National Association for Obsidian Studies being one of them. The Society for Archaeological Sciences and far Western Anthropological Research Group and XRF lab. I have all been really great sponsors for this and helped us put it all together and made it possible. Hello, yes, thank you. My name is Nico Tripsovich of UC Berkeley Archaeological Research Facility. I'm the organizer of this meeting along with Lucas Martindale Johnson and Kyle Friend. I'd like to welcome you to this meeting with and begin with a land acknowledgement. We recognize that Berkeley sits on the territory of Huchin, the ancestral and unceded land of the Chochenyo speaking Muacma aloney people. Every member of the UC Berkeley community has benefited and continues to benefit from the use and occupation of this land since the institution's founding in 1968. So with that, I'd like to go ahead and introduce our keynote speaker. Professor emeritus Stephen Shackley is a highly regarded archaeological scientist whose 30 plus year career has spanned the fields of anthropology, archaeology, geology and museum studies. He was awarded the 2018 Frixell Award for his interdisciplinary research by the Society of American Archaeology. In addition to his long career at the University of California Berkeley, Dr. Shackley is also the former director of the NSF funded geoarcheological XRF laboratory and he continues to teach as an adjunct at the University of New Mexico, serving as director of a new geoarcheological XRF laboratory in Albuquerque. He received his BA and MA in anthropology and geological science at San Diego State University and his PhD in anthropology from Arizona State University. He came to Berkeley in 1990 as a research archaeologist at the Phoebe Hearst Museum of Anthropology before joining the faculty of the University of the University Department of Anthropology. Professor Shackley's main research focus has been on the American Southwest and he is the author of over 130 journal articles and book chapters as well as numerous technical reports. He has also published several prominent monographs and edited volumes including X-ray fluorescence spectrometry in geoarcheology in 2011, obsidian geology and archaeology in the North American Southwest 2005, and archaeological obsidian studies method and theory in 1998. He is perhaps best known for his work on obsidian characterization in the American Southwest where he has been on the forefront of elemental characterization studies using X-ray fluorescence spectrometry. In this capacity he has been a steady voice arguing for the importance of high quality scientific research in archaeology and geological sciences, particularly in the wake of increasing ease of access to complex portable technologies. In addition to a productive academic career, Shackley has extensive experience in museum creation and display, having curated exhibits at prominent museums throughout California and the American Southwest. He has also served on numerous committees and boards, including as president of the International Association of Obsidian Studies, the vice president of the Society for Archaeological Sciences, and associate editor for the journals, geoarcheology and archaeometry. We are honored to introduce Dr. Shackley as our keynote speaker today. Welcome Steve. Thank you. Thank you very much, Nico. After hearing that I do feel tired, as well as retired. So I want to kind of set the tone here. So first I want to thank the three musketeers for putting this thing together, because I know it can be a real pain, particularly since we have to do this by waving at each other, you know, across the, across the, across the miles. Let's see if I can show you this. This was in our local paper. Now take a look at it closely. I think it worked in Ireland for a year. I found that pretty interesting.  It's just pretty great. And they wouldn't publish my letter. This is in the local paper in Albuquerque. They wouldn't publish my letter again. No, they don't publish any of my letters. Okay. This is of course my particular view, and over 35 years. And of course everyone here knows that there's been significant changes in what we do in provenance studies that period of time, most of which I find to be amazing and wonderful. So I'm going to try and do this in 50 minutes so there's plenty of time to talk and ask questions and maybe come up with a few answers. So the first part of this is going to be a little bit tongue in cheek but maybe does have some utility in a way. Since I'm going to make fun of myself so I want to talk a little bit about my background. So we're going to talk a little bit more about how things have changed in our discipline over time. Because I started in the 70s, like Richard Burger did, a little different place. And when I got out of the service, those of you not from the US, don't know that combat veterans get something called the GI Bill, which is actually cash to go to college. I don't know why not go back to college. So that's what I did, although I chose geology in this case, and that worked out pretty good for me you can see this picture down here my senior State University ID that the cool geology student.  I chose when I went. I always hate it when people put these long lists up here but since I'm the plenary speaker I can do whatever I want so that's what I decided to do. So, so what's happened since the 2011 obsidian. The book came out through University of Arizona praise press. So, actually, as you'll see even always spent many years working on sources there's seven new sources or source groups that we discovered. And plus, for my Mexican colleagues that may be online here, 10 more archeologically identified in Sonora but not yet discovered. So we're working on that. I don't understand any of the complexity of the mugging that teal volcanic province sources. Why this might be important to others from other parts of the world is that a number of sources that have the same geochemistry, but a great distance apart from the same volcanic province and I think there's other areas I think of Georgia and the caucus and some others that are like that. So there's a more sites have been added to the analytical pool that's another reason I'm tired. 35,000 more artifacts and been added to the regional archaeological database, and the largest group comes from that late classic social network project. I mean 15,000 and 20,000 samples. And then one that most people don't know about the El Segundo project in northwest New Mexico, which is almost entirely early and middle archaic sites, there's 7,000 samples. And this increases the number in this time period by thousands. So we have Mills and Clark late our class social network project again, approaching 20,000 samples. And Nico mentioned this briefly, all lab reports between 85 and 2016. And he's hassled me to put the rest of them up on East scholarship.org and if you haven't taken a look at that. It's a great open access. A place to go to get almost anything that we at Berkeley have written, including all the garbage, the junk. And a continuing collaboration with my Russian colleagues headed by Ekaterina Kate during a cheva in the caucuses and she's going to give a couple of papers on this. I believe first thing tomorrow morning. And most of the work I do in my lab now on the Southwest is geological. Okay, so, since you've been talking a lot about Berkeley and this Berkeley thing I wanted to bring up a short history of Berkeley's relationship with obsidian provenance and XRS specifically. And while XRF wasn't the first thing. Excuse me Berkeley wasn't the first place to use XRF and obsidian studies. I know that hall wrote that 1960 paper on use of XRF and archaeology, but it was one of the first. And it's created this expansion. Over time, even before I got there in 1990. Bob Jack and Bob hyzer and my department department of anthropology, published the first XRF analysis new world of city, but I know the next year Carmichael and Jack published the chemical fingerprinting of acid volcanic rocks from a geological perspective. And the 70s and 80s. I don't know if either one of these guys are online now Tom Jackson knows as a student of Stanford Richard use it UC Davis, use the same instrument for Northern California city and provenance studies. And then after 1990 after finishing my PhD at ASU coming to Berkeley I use that same spectrum instrument to quantitatively reanalyze the North American Southwest sources. And in the 90s I purchased two spectrase quantum instruments from Intel replacing the spectrase 440 that died. And that was an interesting perspective of those that you've set up XRF themselves. And I'm trying to find the. The rowdy and peak with that took about two months. That was a real fun job. And then oh, oh five I think Nico mentioned this I received NSF sponsorship for eight years to purchase the thermo scientific context instrument training students and XRF and obsidian studies. And that's the same instrument that's all over the world now and been used tremendously I think that the instrument itself is not what's unique but I think the software is one of the best that I've ever used, certainly the easiest, particularly for training students. Okay I'm going to just throw this up here's a partial list of grad students and postdocs. Now mostly faculty, some of which are actually online right now. They were trained in the Berkeley XRS system. So, at least there's that. This is what the lab used to look like at Berkeley, long long gone. I want to talk a little bit about an instrument that a lot of people don't really realize was a Berkeley except for Carolyn certain who did most of registration work on this. And then Carmichael, a very prominent pathologist and geologist approached me to get this Phillips pw 2400 through NSF, which we did do. Yeah, I was a little bit reluctant because I go oh fellas, this is wavelength XRF great instrumental precision but it requires, you know it's going to be a destructive analysis. I received the instrument I found that there was a routine in there to to ratio to the Compton Scatter, as well as the brimstone. So I lucked out in that because the spectrase 440 was dead, it was gone. So that worked out pretty well. So a little bit more history on this. Nico can correct me now but I think that instrument is either completely defunct, or has been scrapped. I think it's gone. And one of the reasons is those of you that work on the geological side of what we're doing is that geologists, geology is pretty much left x-ray fluorescence spectrometry for ICP MS. Certainly because they just later really don't care about whether the analysis is destructive or not like we do. And so if you really look at it x-ray fluorescence spectrometry is spectrometry is in our hands now in archaeology. That's not completely true geologists still use it a bit but mainly it's us. Okay, I've talked about maybe I've talked about this a little bit too much is the importance of a database. And let's see if this works, because you don't have not seen mine. We did this yesterday and it worked pretty well. In 1996, I think Rob Tycott did it about the same time to set up a regional database for Northwest Mexico and the US Southwest on the obsidian sources and pick one here I'm going to return to this a little bit later. Let's try that. I'm going to talk a lot about the Hamas Mountains here so. Your screen is dark. Yes, it didn't come up this time. Nothing showing. Okay, what should I try. I'll try to resume. Okay, now where am I am I back at the first slide. Yes. Why did it work yesterday and not today. Who knows right. Okay. I'll just wave my arms you won't be able to see. So you can look at this and then all of the. I think I can say this all of the known sources in this region are available. raw data, mean and central tendency. Generally the analysis of the oxides as well as the traces are available to everyone and in fact, people that are right actually online right now. So those using portable XRF, use this data set to assign the source and it works quite well. Lee Panitch and Santa Clara University have experimented then he can determine source quite well from this, this data. Okay, so I'll leave that alone maybe what maybe we'll work next time. Okay, so a little more history on this when I. When I arrived at Arizona State University. Frank Bam was beginning a project called the cultural reservoir archaic project large cultural resource management project in central Arizona. And he hired me to do the lithic analysis.  You know go out there, and you could source quote unquote source all the subsidian. Okay well I'll do that I pretty much left geology in the late 70s because all the money was making money in archaeology. So I had done that so I started doing the research, and you can see the map on the left here. Those were the norms known sources of art archaeological or artifact quality of sitting at that time. So, another reason I'm tired is after 35 years. This is what it looks like on the right. Those that are circled in red are the most recent ones ones I was talking about that be more recent. And can you see my cursor. So tank mountains and saline or saline are going to figure prominently here in a little while. When I talk about the issues of similar chemistry. Okay, I think that's enough. One of our former students from Berkeley lead panic I mentioned earlier it's Santa Cruz and Antonio porcato. Who works for Ena and by California, have really done it tremendous amount of work in by California. I often get the question has, does obsidian has obsidian ever quote, moved across the Colorado River from this side, over to this side. The answer is after 35 years we've never seen. It just hasn't happened. The way I explain that, or explain it away is that there's plenty of adequate obsidian sources on both sides, so they really need to do that. It's not that there hasn't been any communication. I think that Sean Dolan is going to talk about the relationship between the Southwest and Mesoamerica coming up. Maybe tomorrow. So there's plenty of communication in this region, but not obsidian. And that's another question that people are dealing with throughout the world. And it's mainly today is going to be a bit more on the geological aspects of what we do and provenance, more so than the archaeological application there's plenty of those coming up. And if we look at it at the continental level, there's a couple of points that are we're talking about and most of you guys know this, but some of you might not. I'm getting into my teacher mode here. The first thing I want to point out is the thickness of the continental versus the oceanic crust. What's somewhat unique about the continental versus the oceanic crust is the proportion of silica that's within that. And as a rare event in volcanic rocks, if it wasn't, we wouldn't be talking right now, I mean it'd be available everywhere, trying to deal with social networking exchange group interaction all that stuff wouldn't be very easy. Would, or it wouldn't be something that we could use to explain that. In the case it's very rare and one of the reasons is that almost exclusively and there's some exceptions to that. Most relic extrusive events occur because a magma plume is moved up into the continental press from the upper mantle and remelted material I'm going to talk about a case in the southwest where was a large pre came here and granite basement that was and that's we think what's causing similar chemistry over a radius of 200 kilometers. So that's something to keep in mind. So there's two general eruptive events that can produce obsidian or I like last, and I was looking through some of the presentations are coming up and there's examples of both of these, and I'll show some from the North American countries. The fusive eruptions are the ones that most people think about lava domes and coolies coolies are essentially a small flow that's occurred from a lava dome complex. Relatively rare and the reason it is of course because in order for us and pathology to classify it as a rhyolite. Proportion of silicon dioxide has to be relatively high in this case, mainly over 70% 78% or more. There's exceptions to that but generally that's case. And of course you have to have quenching and I'll get to that moment. Explosive volcanism not everybody thinks about although I noticed that there's a few papers. They're dealing with looks like what might have been plenty on their subplenium events, of course, made for me for plenty of the younger who was lucky enough to see that the Suvious event killed everybody in her killing and pay and might do it again. And that part of Italy, depending on how fast they get out of there. And some of the city and producing events can exhibit both the fusive and explosive volcanism. Like for me the pre Mount Taylor that's the most Mexican that's the look, let's look at a few of these. I use this image up in the top which is from Richard Hughes and Bob Smith's paper 1993.  And we got there a few weeks later a few months or a year or two later. Not too many look like this although there was a number of them in Southwest to do. So this would be very recent. If you get the conditions to create quenching a classic when the one I were to think about. Frank Skinner certainly familiar with this is in Yellowstone where the eruptive event occurred under continental glaciers. And when you have a two kilometer thick glacier, it's going to cool very rapidly, and it's certainly going to quench, but also can occur. From high wind events. If the event is small enough in order for it to cool rapidly that's another way. I also might interject here that to my knowledge, no one is is actually seeing an event that created obsidian. It's not just a late geologist named McDonald, who supposedly saw one in Ethiopia I think it might have been phantali, but he's gone. So, that also gives you an idea of how rare these events are compared to Hawaii, for instance, result eruptive events which are very common. So here is near and dear to Carolyn's heart, the Glass Mountain event and medicine like Highlands, Northern California we were talking about that earlier.  And there's, there's boulders there over three meters in diameter. What's interesting here is that this is less than 1000 years old. Certainly environmental conditions that allowed this to occur. And this is one of those sources that's of great interest to geologists and pathologists to because of the character of the flow. The de vitrification that's occurred very rapidly, a whole variety of other things that are not generally of interest to us in archaeology. But this is a relatively unique event, not that these don't occur, something like this all over the world, but generally that's, it's pretty rare event. And parentetically, what Carolyn was working on under dissertation was that they rarely you very rarely use this obsidian for production of small by faces. It's almost all those very large by faces that were used in the Urocks, white deer skin dance. And in fact, I've napt this stuff a number of times, and it lends itself very well to percussion but not pressure. This is one I've worked on recently. It's another policy and it's very interesting about 2.2 to 2.5 million years ago this is old this is right on the San Andreas fault line near them, the US Mexican border and Imperial County. And of course, this is distributed throughout that region. Well, very recent. One that I'll spend a little bit of time on is the in the Hamas Mountains is the Cerro de Medio event by us Riley in northern New Mexico in the Hamas Mountains. This is biometrically the largest source in the North American Southwest. You can see those very large pieces. It's about 900,000 to about 1.2 million years old. And there's a video here and I want to hopefully this one's going to work it worked yesterday. And since it's YouTube we're probably going to get some, some damn advertisement first but let's see if work. So Nico let me know if this works. I did yesterday. Did it show up. Yeah, yes. Okay, I'm not going to. There's your ad. I'm not going to make you listen to the ad. The bias caldera is famous, famous, famous to volcanologists and geologists alike, because this is the place where the universal model of caldera formation and development was first devised by Bob Smith and Roy Bailey of the US geological survey back in the 1960s. I can designate the bias as a type, this guy's still alive with the dome, following subsidence with the structural dome. A type structure is the base model used to describe a concept. The bias caldera is used as that defining structure for all volcanic calderas in the world. The origin dome, like redondo P is a structural dome. When the caldera forms. It blows a big hole in the ground because you're evacuating 95 cubic miles of pyroclastic flows. What happens first is that the floor of the caldera collapses, and it fills in with some of the pyroclastic material. The magma body is still rising. It's less dense than surrounding cold country rock. And as it rises, it pushes the floor of the caldera up into the sky. And redondo peak is a result of that uplift of continued magma pressure from beneath. So when you look at the rocks, the geology of redondo peak, what you're looking at is uplifted. Bandal are tough that at one time was in filling the hole, but the magma body has pushed it up in the sky, and you see that it's broken into a multitude of faulted blocks. One of the beautiful things about bias is that all the features are so perfectly exposed. You have this symmetrical circular caldera. You have this. So, can you hear me. Okay, yes. So this is Gerald a radio and you get an idea of that size. And this is part of that large ring eruption that's very well preserved. And I would add that I spent quite a bit of time working on these sources up there. And I have met geology field camps from all over the world. Germany, Mexico, and certainly the US, because this is the type site for this kind of eruptive event. Centralized resurgent dome with a dramatic uplift, you have an almost a perfect ring of rhyolite domes that have erupted along the ring fracture zone. And so you can put all this together and create this model other calderas it's not as well expressed. And so it took the work of these two guys at this place to develop the model that became so universally accepted and used to this day. All right, so do I stop this share and do a new share to get back. Probably, let's see what happens when you close it. Right. Yeah. Is it good. Yes. Okay. So, the geologist that was speaking is Fraser Goff, a guy I've been collaborating with for about a decade now. We publish into Mexico geology bear her bri lights, and I do a lot of the oxide analysis for him in my lab. And you can see the cell Dometio dome complex here, and that size. Now, there's obsidian sources that we work with all over the world of this large but in the Southwest, this is one of the major sources. And relatively recent. Okay. Another one that's very important for those working over farther in the West is government mountain dome complex. When I got there in the 80s. You could still get nodule sizes, half as big as your car and now you're lucky to get one as big as a rock hammer, because unlike the bias caldera that's in a national park protection system.  All right, let's get a little bit earlier here into the knee gene. These are the same kind of a fuse of events. But you'll notice that in general, most of the original obsidian has a de vitrified into pearlite. What's important here, and these more recognized sources are all over the world, certainly is that the obsidian that's left was probably the most vitreous and the driest in that original event. And so the quality is very great. The nodule sizes generally are quite a bit smaller of course than in the paternity. It doesn't mean they weren't used. They were certainly used from the paleo Indian period in the, in the late Pleistocene all the way through the colonial period, and I'm sure that we can say this all over the world, the same thing. These are just some classic. All right, this one here at sand tanks. You notice that all the fertilization that's occurred with the remnant Americanites. And some of these are quite are quite large. This is at Antelope Creek and meal Creek in Western Mexico. I'll return to that a little bit later. Here are some other examples. Sand tanks again was it deals to allow a northern sonora, which is fairly recently discovered. I'll tell you a story about me and the quality of my field work. There's another source nearby called los videos appropriately for those of the Spanish speakers here. We, we discovered this in the 80s. And it's very excited about it. We came up to wash recorded that source. And within 200 kilometers where we were was this other source that remained an quote, an unknown to Steve Shackley for about two decades. So this goes to show you you got to look around. Okay, look, violent eruptive events events that can occur, produce obsidian. I use this one because everybody's familiar with this Mount St. Helens which of course is not Rila it was an anti state strata volcano but everybody smear with it. I'll have a video in a moment to show this. This is also the sequence of events in a collapse called era. During the planning phase and then the ring eruptions. Volcanic history in the Hamas Mountains began long before the Caldera farm. First eruptions occurred here more than 15 million years ago. And so much of what we see here behind us are the rocks that were produced by those earlier eruptions. Lava flows and layers of pumice and ash that accumulated on the landscape and built up the mountains before the vias caldera tore them down. Fast forwarding to approximately 1.6 and 1.2 million years ago, the vias caldera was the epicenter of two massive volcanic eruptions that left deposits several hundred feet deep in the surrounding area. The most recent eruption emitted an astounding 300 cubic kilometers of molten rock and debris before collapsing into the vacated magma chamber leaving a depression 12 miles wide that can be clearly seen from space. Well the type of eruptions that happen at the vias caldera are impossible to imagine. The ground probably shook for months. Earthquakes every day. There might have been smoking ground. But once the crack opened and the volcano really got going, it started with a blast. A huge huge crack of thunder magnified thousands or millions of times. The initial blast sent out a shockwave so powerful it compressed air to the temperature of between 400 and 500 degrees simultaneously leveling forests and incinerating trees. But that was just the beginning. Huge toxic steam clouds billowed from the volcano's mouth skyrocketing some 30 miles into the stratosphere. Within minutes chunks of pumice rained down. The column eventually collapsed under its own weight and crashed to earth sending superheated torrents of ash, steam and gas racing across the countryside at supersonic speeds and forming the dramatic maces of the bandolier tuff. Eruptions may have continued for weeks. Many of us remember the destruction rot when Mount St. Helens erupted in 1980. But scientists believe the eruptions of the Vias Caldera were up to 250 times more powerful. Amazingly, the Vias Caldera isn't even the largest caldera in the state. That title goes to a collection of calderas in southwestern New Mexico that are some of the biggest in the solar system. Debris carried aloft by the ash clouds can be confirmed as far east as Kansas, Oklahoma and Texas. And some scientists speculate ash may have reached the east coast. Well, let's believe the dust cloud would have blocked out the sun over much of the United States for years and altered the world's climate. This will happen again, perhaps not at the Vias, but at some other volcano here in the west. And when it does, it will truly stop life as we know it. So, this is another example of ash low tough eruption, called around the world often ignombrites, although ignombrites for me is when the tough is welded. This is not a welded tough, but anyway, you can see what we call obsidian lapeli and petroleum lapeli is generally those pirate class less than 64 millimeter so they can be larger. But generally that's the case here. This is it. Laura Mesa, Mount Taylor. Fraser got mentioned the band of their tough that was from the Serral Toledo eruptive event. And all of this upper member of the tough here is full of obsidian that was quenched as and that that video would have showed that graphically. As the ash low tough was occurring, it usually moves at supersonic speeds and any lava within it. If it the glass warmers are high enough silicon aluminum oxides, it will create obsidian. And I have an example from Russia coming up that you'll see from the caucuses are the same thing. Let's talk a bit about secondary deposit issues in our area and of course all over the world, and this eruptive event was so large that it through this ash low tough down into the proto Rio Grande, and you can find this obsidian all the way to Chihuahua. This is an example from the caucuses we published this in the iOS bulletin actually was I a cool or box on source in the caucuses. And this is pretty classic look. This is quite an advantage you can see, and where this guy is standing there's nodules like this, in part of the vitrified if you can see it. The nodules are quite large 78 centimeters so this is a an important way that obsidian is produced. What's important for us, and I'm going to talk about that in a few minutes is that this is courses very friable. It enters in the environment through erosion, and can be distributed over great distances. What's important. I'm going to spend a lot of time on this that the range of variability of obsidian sources around the world. Paralumnius and Peralcon are probably the two major classifications for while, while Canucks at least as far as obsidian is concerned that we can classify Peralcon obsidian. The most famous example is Pachuca in Mexico. The reason it's so green is because the, you see in these propellants, the proportion of iron is very high. The same thing those of you. There's not many historic archaeologists here but green bottle glass is green for that very same reason. Often in Peralcon glasses, zirconium is very high. The two regions where there's quite a bit of Peralcon is the Sierra Madre Occidental in northern Mexico, and of course the Great Rift Valley. Now, we don't usually think about total alkalis silica plots, and the work that we do, but recently a project in Northwest New Mexico, this has become valuable. Many of the projectile points are made from a whole variety of different volcanics, including something I never would have considered trachea basalt and basalt agandasite. But in that early archaic they were using it. Nobody really knew where these sources were. And by determining the rock type, we were able to go back to the geological mapping and find some of these sources. So this is another method that we can use. And I know I'm going to forget his name, the guy at Montreal. Sorry, I forgot his name, especially if he's here. But he's been doing this in Canada too. It's very useful. Okay, I want to spend a little bit of my time here. A few minutes talking about the role of secondary deposition, or what is an obsidian source. And I know many of you think about it. It's been a big deal for us in the Southwest, both in the Gila River system and the Rio Grande. So when I was running my field practice in archeological field camps in New Mexico in the 2000s, we began to collect the secondary deposits along obsidian along the Rio Grande. This exclusively comes from the Hamas sources, which I talked about earlier, and Mount Taylor over here, coming through the Rio Marco into the Rio Grande. And I often tell my students, and I'm a flint knapper to when you carry everything that you own on your back. So when you think about that, I drive a pickup around the Southwest, but when you carry everything in your back, back you're going to be pretty parsimonious about where you get raw materials. And if you can pick it up close to where you're living. In this case along the Rio Grande that's what you're going to do. But is it an issue of epiphanality. It could be from the primary source but it could be from the secondary deposits so what we did was we looked at 11 sites along the Rio Grande, and collected in six areas along 400 kilometer area in the Rio Grande, and to make a long story short. Indeed, the correlation between the mix of sources at various areas along the Rio Grande, and the sites that were nearby was almost one to one. So if you're making an argument where, where are they getting this. And we're all interested in exchange and group interaction I mean, and we have fun with our instruments. What you have to do is understand the past and explain social networking group interaction, and all of these different things. This is the kind of thing that you really have to do. So I'm just calling your attention to the, the issues of secondary deposition and keep that in mind. It's not always an issue one of the sources, the one that we saw exploding. And this is a video from the bias right light. That's fairly recent. The eruptive event wasn't very plenty and they're supplementing, and it didn't get outside of the caldera. So we don't find that in the Rio Grande so that if we find it in archaeological sites in this region. It's got to be from the primary source. I want to beat that to death. This is some of the caldera and pre caldera sources we've been working with. So there's eight million years of eruptive events that have been emptying into the Rio Grande and the proto Rio Grande. And by the way, that river, the Rio Grande is only about four million years old. So those of you familiar with Western North America know how active tectonically it is there. And that's another example. Okay, I bring up Graham Mord's paper all the time, mainly because I made students read this it probably hated it on the ease of sourcing artifacts and the difficulty of knowing prehistory. That's what we're really doing here. I mean it's fun to do the science and determine the source, but we're trying to know prehistory. Again, I'm. So we still I still have some issues in the Southwest.  Again, this is an issue of having sources that are not near each other with similar similar elemental composition. Also, I'm not going to talk about the autonomous mountains today, because I spent all that time trying to get this to work. So the elemental discrimination issues again, saline or saline a sonora versus tank mountains. And how we're dealing with this. Now the muggy and that teal volcanic province study has come up. And these of course are near Jean they're very early. And I'll say that as far as I know, the oldest dated artifact of city and in the world is one of them that we found here called that mountain that over 31 million. The reason that's an issue of course is obsidian as a disorder substances moving toward an order state through absorption of water and of course that's the basis of hydration. So it's not generally very old doesn't last very long geologically. So we were quite surprised to get that kind of day. But what we have here is over a radius about 200 kilometers a composition that is very similar. So again if you're interested in generating models of group interaction exchange, you damn well better be able to separate or discriminate these things so there's a number of ways to do it. So what we did is went to various granny agencies and decided to let's date these are they similar in age. That would make some sense. They asked isotopically different, are they the same. And what is their elemental composition, and which we did. Let's see if I want to go to the next. Yeah. So the first thing we did was date all of these. And in this volcanic province, you'll notice that the earliest dates are in the south, and it moves through this to the latest date so it's moving south to north, mainly because of tectonic processes and I'm not going to get into. And so that's fine so we know that. And about this time, I talked to a geologist, late geologists at UNM named Wolf Elston, we've been working out here for God 40 years or something. And he was convinced that there was a granite basement. And we've been working on underneath all of this. And so, all of these sources had been remelting that granite basin basement, a basement that probably has very similar composition over a large area. So let's see if indeed that that's the case. So this is, sorry. This is what we're dealing with here. And these two here. Mule mountains and not mountain are the ones that are the farthest apart of course, and the most similar elementally this is called the Murphy's law of obsidian provenance studies. You know this kind of stuff always happens. We were able to elementally separate it a little bit if you look at these numbers it's not very much with barium. And I throw barium out because only recently have portable extra instruments be able to get to 50 KV and do that and I believe that I was talking about the new broker that's can get to that either that are Matt, one of the two. And this makes a very big difference why is that. I don't want to spend a lot of time talking about incompatible elements but barium happens to have very high ionic charge and it has difficulty finding mineral hosts in the solid phases. It stays in that melt for a long time. So barium is very useful at least for us in Western North America discriminating sources. Just want to throw that out. And of course in the laboratory XR even able to do that for a long time. And this this plot here makes isotope geochemists just grind their teeth whenever you plot age against isotopic composition but it works very well for us. Okay, and that's what we did here. I'm running out of time to stay online. Okay, another two sources that are as you can see here are great distance apart, have very similar elemental chemistry, at least in the mid Zs. And again here is barium that really helps discriminate these. So if you're working in the Southwest, and you're only able to analyze the mid Z elements, you can be in trouble. And these are this this one here and this source and sonora is distributed over a very large area well into above the border. So it's important to be able to do that. Okay. Final thought we'll see if I'm going to be able to do this. So in regards to whether your data are acquired through PXR effort lab XR effort ICMS or any whatever it is. I think we're in dire need of international city and database.  And if I am for instance, I'm somebody sending me something from the caucuses. And it's very difficult to fair it out the data on those sources. And I think I'm not going to do this but somebody here needs to do this, we need to have an international database. We've just done a great job in the Americans, putting that together, at least North America. But we need to have need to have not only physical description of the source and the bibliography, but also the raw data. Lucas was talking about publishing also, I think peak and background intensities and error. That's, I haven't done that, just publish the outside and ppm values but. And mean and simple tendency, including minimum maximum maximum really helps you assign the source it does me. Now I'm going to try this and see if we can do it again. So if I want to go to my website. Alright, so this is what I've done, and probably a lot of you seen this thing. You can click on this which one I want to go to. And of course that, having the images that's great to, but this is what we really need. Now I also analyze the major oxides to values plots. Maps of the location of sources that comes as the source composition you've seen this before this kind of thing. That's got a cow canyon. You're really good be helpful to have something like this. This is what I'm talking about is providing the mean intent and central tendency, especially minimum maximum you know what the range is at least that ability, and a number of people in North America with portable X or F and been able to use these data and assign the source. Yeah, I know right Lucas. I know, I know that Matt's done it. A whole variety of people have done it. As far as I know as long as you have a good understanding of your calibration and maybe even some scans of some standards. Yeah, okay that's a secret. Yeah Lucas that's the secret word standards. Jesus, come on you guys analyze the same standards, at least international standards so you can go and compare it. There are some differences between the results from the broker and my laboratory X or F, but if you look at the analysis. I use RGM one a lot or IGM two. You can standardize the data. And it works quite well. The simple thing so I've been lecturing enough, and I'm going to stop. Okay, I'm going to stop share. And anybody that has, let's see how much time we got, we got about seven minutes. Okay, are there any questions are preferably answers. If not everybody go to the bathroom or go have some coffee. Steve, I have a quick question. And this is more on the archaeology side in particular, whether there was any control over the territory, where these obsidian sources were that might have affected the actual use coming from different places. Yeah, that's a really good question. There is one great example of that in Arizona. There was more about 80 1300 I think this is what you're asking. There was a source superior picket post mountain that was used throughout the region. After about 1300 when with the rise of what's called Salado, which we all argue about whether really exist or not. It was territorially circumscribed and was no longer available. That's a really good example of that I think that's what you're talking about isn't it Rob. Yeah, I'm sure you probably have the same kind of thing in the Mediterranean. Does that make sense.  All right, well, thank you Steve. That was a really wonderful talk and inspiring how much information you put on your website, more regions have that kind of detail on their sources and the country. That's why I'm tired. So, I'm sorry about. It was funny yesterday we tried this and everything worked fine and now it's somewhere. Yeah, we'll help others have more luck. All right, well, Well, thank you very much. Yeah. Thank you. Yeah, thanks. No beer though. Well, people you'll be around if people have further questions right we can catch you on a in between other talks maybe. Well, let's get the landscaper's here and they have some questions for me so I'll be back in a few minutes. Okay, great. Thanks again Steve. All right, well let's go ahead and begin with our first talk of the session. Today we have, we're beginning with the chat on the obsidian source and its role in the pre-Hispanic exchange networks of the city kaka basin, presented by Richard Berger, Martin Gueso, Vanessa Jimenez, Bob Goldstein and Michael glasscock. Richard here with us I know. Welcome. Hi. Can everyone see this. Yeah. Yeah. There we are. Well, thank you for the invitation to come and it's my pleasure to be here and speak on behalf of the group of people that were just mentioned. In the 1970s, 846 obsidian artifacts from 98 archaeological sites, improving Bolivia or analyze that Lawrence Berkeley lab with Frank Isaro and Helen Michael in a pilot project that was designed to provide foundations for the study of obsidian trade and exchange in the ancient central Andes. The results were published in 1977 at LBL and also in Peru, and permitted the identification of eight compositional groups or types from Peru and northern Bolivia. And at the time, none of these eight compositional groups could be linked to geological sources of obsidian. But in the following three decades, seven of these eight compositional groups were successfully matched with obsidian deposits located in the southern highlands of Peru. And one of these, the key species saw source, the alka source, and the device source accounted for most of the artifacts. In the report of the results from Lawrence, it was acknowledged that the geographical distribution and sampling of obsidian artifacts in the study was uneven and unsystematic. But it was really quite likely that additional sources existed above and beyond the eight originally identified. And reflecting this reservation, 12 obsidian artifacts that didn't fit into any of the eight original compositional groups were analyzed by neutron activation. Their trace element abundances were published in the LBL publication as rare types one to eight. And it was suggested that some of these rare types could come from sources that were important in antiquity, but were scarce in the sample that had been looked at. And then not much happened for about 20 years. But 20 years later, I did some research with Sergio and Karen Chavez along with Frank Sorrow, looking at a large sample from the Lake Titicaca area and Cusco. And I found that there were a substantial number of artifacts that match what we call the rare type one. And they were especially common at a site called Tumuku, and we began calling this the Tumuku type. And based on the number of sites where these Tumuku type artifacts were located. We suggested that in fact, the source was probably located somewhere near the border between Peru, Bolivia, and Chile. And because of the frequency at the Tramacda pre ceramic site as well as the Tumuku site and here's Lake Titicaca, for those of you who are unfamiliar. Shortly after that, Martin Gueso launched a study of obsidian recovered from the famous site of Tiawanaco and related Bolivian sites. And he identified additional chemical groups, three of which were matched the geological sources in Bolivia. And one of the compositional groups that initially he didn't have a source location for, and was particularly common at the conco Juan Cane site in Bolivia. So he began calling it the conco type. In this talk, I'm going to present evidence of an obsidian deposit referred here as the Cherania source that matches the chemical composition of both the Tumuku type, or our rare type one and the conco obsidian type. It's located as expected in Bolivia near the border with Peru and Chile, although the distribution of the material from the source was not extensive. It has a history of exploitation that spans over three millennia. Our sample of obsidian artifacts from the Cherania source remains small but the available evidence suggests the exchangeable kind of glass from the source increase during the middle horizon, the period when this region was dominated by the Tiawanaco culture. In 2007, Vanessa Jimenez, then a student of archaeology at the Universidad Nacional de San Andreas La Paz identified the Cherania source while doing a regional survey for her licenciaturas thesis. The geological source labeled PAM 16 in her survey, which you can see down here. It's located at 3998 meters above sea level in the Marca Nasa Valley, 14 kilometers east of the town of Cherania. I'm in the province of Paca, his department of La Paz. The site is located in the high grasslands in the headwaters of the Mallory Valley. And in this region, there exists a variety of raw materials that were used in pre Hispanic mid times for napping including obsidian church Chalcedony the salt Jasper day site and Opal. The geology of this region is characterized by neogene magnetism, but I'm not going to really go into the detail in the into the geology. At the upper most level, there's a layer of Raya light and it's adjacent to a volcano, which is called the Seric volcano and a French group that studied the local geology thinks that the obsidian may have been produced by the eruption of that feature. The tyrannosaurus is situated on an arid plateau between the Marca Nasa and can you valleys, small obsidian nodules are scattered over the surface for approximately half a heck there. The tyrannosaurus obsidian is dark gray to black and appears translucent or opaque. Most of the nodules are small and rounded usually less than five centimeters in length. An example of unworked modules was collected and it at the locus and then it was taken to the Missouri research reactor for compositional analysis. Jimenez located 24 sites in our archaeological survey of Bolivia's Western Cordillera and obsidian was widely used for artifacts at these sites and enters survey to recover. Many flakes and small projectile points. About 9.5 kilometers from the tyrannosaurus near the juncture of two rivers was the site of PAM 10. This archaeological site covers about a hectare and a half. The residential camp where lithic production took place at 3962 meters above sea level. It seems to be slightly warmer area, and it's covered with debris suggesting abundance stone tool manufacturer. Here the stone nodules that had been brought there were no larger than three centimeters. The obsidian artifacts in the study. We're submitted to the mirror archaeometry lab at different times between 1992 and 2005. The geological samples from Turania were submitted in 2009. All the artifacts and geological samples were analyzed by neutron activation analysis using procedures that Mike Lascaucas described elsewhere. Now, some of you may know Mike and I want to show this picture. What's remarkable, particularly in light of the previous talk is that when we compared MERS results with the results from Berkeley that had been done almost half a century earlier. They provided almost a perfect match between our rare one or the tamuku type and the Turania source which shows you here this piece of information had languished for 50 years without any apparent use, but now it turned out to be important. The unique composition of the Turania source relative to other sources in the region is illustrated by a plot of the elements cesium versus half neum that you see here. But several other elements, such as manganese rubidium and also support difference between Turania and other sources. The red plot that you see shows the artifacts analyzed in MERS and Lawrence projected against the 90% confidence ellipse from the Turania source as derived from the 10 geological specimens analyzed and confirmed that the tamuku type artifacts are in fact from Turania. These are the conco artifacts that had been analyzed by Martin Jesus. The identification of the Turania source permits a preliminary review of its distribution prior to the Spanish conquest and a consideration of the implications of this patterning. As noted, the Turania source obsidian appears as nodules scattered across land surface, none of them larger than five centimeters on the side. This would have limited their utility for the production of large obsidian artifacts, but the nodules still would have been appropriate for making flakes and small tools. The size of the Turania nodules is in stark contract to the blocks, large blocks of high quality obsidian found at the Chavae source in Arraquipas Colca Valley. Not surprisingly obsidian from the Chavae deposit was heavily exploited throughout pre Hispanic times, and it was the dominant type of obsidian used in the Titi Kaka basin, including in Tioanaka. Nonetheless, despite its intrinsic limitations, Turania obsidian was utilized beginning in pre ceramic times and continued to be used for several millennia. Unfortunately, at present time the relatively small number of obsidian artifacts analyzed from the southern Titi Kaka basin limits our understanding but some tentative conclusions or discussion at least can be offered. In our sample 29 artifacts recovered from seven sites in Peru and Bolivia were made of obsidian from the Turania source. Three of these sites are pre ceramic in date. One is formative in date. One is early intermediate period in date and two others date to the middle horizon. The Turania source was exploited despite the size of its small obsidian nodules, located in the high grasslands near the upper level of agriculture. This geologic deposit was initially utilized by hunters and gatherers in the zone immediately surrounding the source. And then by agro-pastoralists who combined their herding of domesticated chameleons, yamas and alpacas with the farming of high end altitude and being crops. Obsidian was collected from the surface in the form of nodules. And at least increased ceramic times it was then transported to nearby locations, such as the rock shelter PAM 10 in order to be worked. The high quality of the Turania source obsidian, which is free of bubbles cracks and inclusions was appropriate for producing sharp edge flakes and small tools including projectile points. Like other minor obsidian sources in the central Andes, such as the Pusilana source in Ayacucho, the Lisa Wacho in Potrero Pampa, sources in Aparimac, and the Akonkawa source in Puno. Obsidian sources characterized by small obsidian nodules were generally of local importance with a restricted range of distribution. Even the Makusani source in the northern Titicaca basin had a range of no more than 120 kilometers, despite the exceptional visual attractiveness of its obsidian. In the case of the Turania source, before the middle horizon, its utilization seems to have been limited to the Alpiplano of the southern Titicaca basin with a distribution of between 120 and 140 kilometers. At the pre-ceramic sites, Turania artifactual obsidian appears primarily in the form of flakes and by faces, such as knives and projectile points. The flakes were probably used for butchering, scraping and cheering while the by faces were probably used for hunting and interpersonal violence. Pre-Hispanic hunters and herders preferred to make their obsidian tools from larger nodules of volcanic glass, and consequently they made the extra effort to acquire it from the major source at Javai, where blocks of obsidian sometimes measured up to 30 centimeters on the side. At late pre-ceramic and formative settlements like Kel Katani in the headwaters of the Asmori drainage, the occupants acquired most of their obsidian, some 77% from the Javai source in the Colca valley, despite the proximity of the Turania source. So the Javai is 250 kilometers away versus the Turania source, which is only 60 kilometers away. The pattern of augmenting or replacing the small local obsidian source with obsidian from a major source continued unchanged after chameleon herding in high altitude agriculture came to fully dominate the Altiplana. Although minor obsidian sources such as the Turania source did not play a central role in the regional pattern of trade and exchange, the sourcing of volcanic glass can provide insights into the movements and social relationships of the inhabitants of the people living in the Turania area, where today a border exists between Bolivia Peru and Chile. If pre-Hispanic people from this zone traveled beyond their homeland for exchange kinship obligations, or other purposes, it would be expected that traces of their short term presence might be left in the form of small amounts of obsidian debitage or tool fragments, constituting less than 3% of the total obsidian assemblage. Viewing the occasional presence of rare obsidian pipes as an index of these kinds of ephemeral interactions or visits, rather than as part of a formal provisioning strategy, suggests alternative interpretations for the presence of a small number of obsidian artifacts from small sources. For example, in the case of the Tewanaco capital in Bolivia, Turania obsidian constitutes less than 2% of the obsidian found at the site. Its presence at a minor mound or settlement such as Moyukontu can be hypothesized as the result of pilgrims from the Turania zone or visitors to kin visiting the urban center. From this perspective, the emergence of a large civic ceremonial center such as Tewanaco would be understood as providing the rationale for Turania source obsidian to be carried beyond its normal restricted use area. The presence at Tewanaco of a dozen types of obsidian from different sources in Peru, Bolivia, and the borderland between Chile, Bolivia, and Argentina can be interpreted as a testament to the cosmopolitan character of that site rather than a reflection of a complex system of lithic procurement. If this perspective is adopted, how can we interpret the lack of Turania source obsidian in the central and northern Titicaca basin and its analogous absence in Arequipa and Cusco? Given the large samples of obsidian that have been analyzed from these regions, we do not think that the observed pattern is the result of inadequate sampling. It seems more likely that the Turania area was relatively isolated and had only weak of any social and economic ties to peoples residing in the central and northern Titicaca basin, Cusco and Arequipa. Given the pattern described, how should we interpret the obsidian and analyze for the middle horizon site of Omo in the Asmori Valley? Here's Omo over here. The Asmori Valley is over here. Turania is located over here. At the site of Omo in the Asmori Valley, 54% of the current sample analyzed comes from the Turania obsidian source, a lowland Tiwanaco provincial center located 170 kilometers from Turania. It's the only site outside of the Pune environment that has yielded evidence of volcanic glass from the Turania source. While at first blush, this predominance of Turania source obsidian appears to be an anomaly, it is in fact consistent with Paul Goldstein's interpretation of the site as being the result of a diaspora of diverse groups living in the Turanaco region and neighboring areas of the Altiplano. Tiwanaco culture pastoralists and agriculturalists settling in Omo continued to maintain their links with the related communities in the Altiplano. Sometimes in the form of Yama caravans connecting the high grasslands with the warmer climbs of the mid-coastal valleys. While the western Altiplano has thus far yielded little evidence of a Tiwanaco road system, the least cost path corridors for caravan routes between the Moquego Valley and Tiwanaco pass well to the north of the Turania source. After these circumstances, Moquego's provisioning with Turania obsidian took some effort suggesting an arrangement with partners in Turania perhaps in response to Omo's isolation from Tiwanaco's Chivain network. Obsidian from the Turania source could have been brought to households in Omo as gifts from relatives or friends coming from the Bolivian Altiplano within the context of Andean reciprocity or by pastoralists leading Yama caravans to the coast, opportunistically picking up exotic materials such as obsidian nodules for gifts or exchange items along the way. Well, thank you. That's it. Thank you Richard. We're running a little late here behind, but do we have any quick questions? We can hit Richard up with questions later. Okay. I have a few, Richard. Let's move ahead. With the next paper it's obsidian exchange among hunter-gatherers in northwestern Patagonia, presented by Fernando, Francietti, Clara, Ota, Ota, Ota, Ola, Laura Sargan and Miguel Giardina. I'm sure who's going to be presenting. Hello. Yes, we can. Thank you. Well, good morning or good afternoon. Please be patient with my accent. We present obsidian exchange among hunter-gatherers in northwestern Patagonia. In this graph, we observed that local raw materials such as basalt and crystal-piston were predominant in the Diamante Valley. As you can see here, the gray part of the graph showed samples from the highlands and in black from the pigment, and we observed very low proportions of obsidian in compared to the other raw materials. The goal of this paper is to assess the convenience and use of obsidian as discussing aspects of mobility and exchange within hunter-gatherers from the Diamante Valley where obsidian was relatively rare. And where research questions are, was obsidian acquired directly or indirectly? Can we interpret exchange from some obsidian sources? In this figure, we observe the three locations that represents highland villages and El Indigeno, the highlands with the site Perdido 1 and the pigment with unit 115. We also observe the obsidian sources identified in this work, Laguna del Diamante, Las Cargas, Maule 1, Maule 2, Coche Quemado, El Peseño 1 and 2. It is important to mention that during the late Holocene, for southern Mendoza, we have observed an intensification process with the broader diet breadth, an expansion of social networks, technological changes, such as the incorporation of ceramics. All these ideas are being understudied at the moment by our group. To explore the use of obsidian in the Diamante Valley, we propose two hypotheses, one of direct access to obsidian and other indirect access and therefore to exchange. For direct acquisition, we expect a source to have a high representation among the assemblies. All the stages of reduction sequence would be present, coarse, flakes, with and without cortex, flakes with age maintenance and tools. There will be high diversity of artifact types, for example, projected bones, side scrapers, scrapers, knives and vices. And we would observe abundant cores, high proportion of cortex and low resharpening of tools. For indirect acquisition, we expect a low frequency of a source present in the assemblies. We would observe only the final stages of the reduction sequence, with exalted cores, flakes without cortex, flakes with age maintenance and tools. Low diversity of artifact types and absent or exalted cores, also no cortex present and high resharpening of tools. We chemically analyze all the recover obsidian from the Diamante Valley with a size larger than 8 millimeters. The 180 obsidian sample include surface and stratigraphy assemblies. We use the XRF portable spectrometer from the University of Nevada, which Christopher Morgan brought to Mendoza. We only included variables from mid-Z elements, which can be detected with little background effect. We loaded the geochemical data into the freegal software. The ellipses were more clear when we worked samples at the level of their geological site. However, we present the ellipses graph with all the samples included. Here we show the map of Mendoza in the upper right with the obsidian sources. In the ellipses graph in yellow are samples from highland villages, in green samples from the highlands and in light blue samples from the bitmap. We could determine that 70% of the samples belongs to las cargas, 7% to el peseño 1, 4% to el peseño 2, 8% for cochequemado, 6% for el maule 1, and 2% for Laguna de Amant. And finally, 1% for el maule 2. From the central place of the basin, las cargas is around 150 kilometers per distance. It's the most abundant. In contrast, Laguna del Diamante is around 70 kilometers away, which is the closest source, and is the less abundant. The first prediction which relates direct acquisition with proximity did not meet. From the 180 analyzed samples in the Diamante basin, 58 had chronological association. Despite archaeological sites at the basin have chronologies from the Hurley Holocene, in this analysis we had only lake Holocene samples. We divided the sample in 500 years intervals during the last 2000 and 500 years before present to explore the variation in the use of sources through time. As expected, in a context of exchange, the number of exploited sources increased a long time. We observe that las cargas persists being the most used source and also increase its uses in later times. This might be because las cargas was the best quality source among the region in terms of sizes of cores and properties. It caused our attention that even during the last 1500 years, when the intensification process occurs, hunter-gatherers use other sources but still seem to prefer las cargas. We also explored trends in the relationship among sources and the use of space in different ecological zones. You can see here in the right the different images of the different environments. The Highland villages, which are located above 2,600 meters above sea level, the Highlands with an altitude between 2,000 and 2,900 meters above sea level and the Piedmont with an altitude between 1,000 and 1,900 meters above sea level. Las Cargas source is the most abundant in the three ecological zones showing again that there is no relationship between distance and abundance. We inspired part of our work in this amazing book and here we have a chapter from Kelly to 2011 who summarized the average maximum distance for logistical forest among different hunter-gatherers. He established that on average we could think of a 175 kilometer distance for these trips considering a travel rate of 40 kilometers per day. But this distance and travel rate might be considered an acceleration and therefore he also explored a radius of 88 kilometers considering a travel rate of 20 kilometers per day. Despite we know there are some groups with larger logistic trips, we use this logic to generate this ready for the Yamante Valley to the sources. This major circle in orange is the 175 kilometers radius and in yellow the 88 kilometer radius. If we consider the 175 kilometers radius, Laguna del Maule 1 and 2 and Cochequemado all outside the expected logistical forest zone. When we consider the 88 radius of the sources but Laguna del Yamante all outside the expected logistical forest zone and only Laguna del Yamante is in the circle. We must also consider that both ranges are accelerated when we add terrain constraints and time expended in hunting and securing subsistence during the trip. In some we consider that an embedded acquisition of logistical trips of obsidian was very unlikely. Therefore, we suggest that obsidian acquisition was product of conveyance through potential hoods visible in their least cost path analysis. In the pit moon, despite el peseño is a good quality source and is closer than las cargas, it presents very low percentages. Why do we observe this pattern? Which was the role of las cargas? Does this imply that the pit moon had higher reliability in the mobility year round pattern towards the highlands in the west in opposition to the east? This pattern may support the idea that las cargas had a direct access as we observed in the variables above, while the others sources had an indirect access. The least cost path from the highlands indicate all sources are 70 kilometers distance or more. This consolidates the idea of non-local availability of any of these sources. We observe a similar pattern than the one observed in the pit moon. However, we identified the presence of obsidian from Laguna del Yamante, the only source that has a path exclusively from the highlands. The access to the rest of the sources implies a path through the pit moon or the lowlands, suggesting that even the sources in the whole visera like las cargas and el maule 1 had access from lower altitude from these locations in the highlands. Therefore, we consider that even for many areas of the highlands, mostly those adjacent to the pit moon, there were paths that favor north south roads at lower altitudes. In a context of territoriality and enhance of exchange, this would imply that areas further south in the pit moon lowlands like Jancanelo or El Nevado may have been hotspots for exchange circulation nodes. We observe that only three sources were used in the highland villages, las cargas, coche quemado, and maule 1. The importance of las cargas may be explained by the access through a corridor and roads. In addition, this route from las cargas to Laguna del Yamante connects the four highland villages, Los Peucenes, Risco de los Indios, El Indígeno, and Laguna del Yamante located there. This route may have been a crucial node of exchange networks across the highlands with its implications to the complementary networks in the eastern side of the Andes. We may hypothesize that las cargas obsidian was acquired indirectly through El Indígeno or other highland villages, as the list cost path indicated that the shorter distance to las cargas from the Yamante valley is El Indígeno. It is probable that the groups from the pit moon and the highlands acquired obsidian from las cargas in El Indígeno. This notion may be reinforced by the presence of force from las cargas in El Indígeno and presence of projected points and bifaces in the highlands and the pit moon. In a context of high mobility and therefore for direct access to all the sources present, we would have expected that all sources had similar representation, showed similar plate sizes, variability, and diversity of certified types regardless of distance. This was not the pattern in the Yamante valley. Following the expectations, we observed that las cargas has direct access while the other sources have indirect access. Las cargas source, considered the best quality source is the most abundant, has higher artifact called class richness, present presence of all the reduction segments, higher variation coefficient for size, and higher frequency of force and core flakes. Closer sources should evidence higher frequencies, higher variability of sizes, some small force to be also present and high diversity of artifact types. In contrast to expectations, Laguna del Yamante did not show abundant frequencies in the Yamante valley. In a context of higher use of local raw materials, basalt and crystal-crystalline, the closest source Laguna del Yamante indicate legal use. Las cargas was the main source used and its importance increased in the late Holocene, despite the use of other sources. The use of obsidian in the Yamante valley, framed in mobility exchange routes, may find a model in the list cost analysis. However, hunter-gatherers surely follow the courses of water across an arid and altitude landscape, many times ignoring a straight-efficient line in a span that do not secure water. Also, these routes, and mainly for the occupations in the highlands or highland villages, accommodated to specific patches of resources where the gregarious populations of Guanacos travel in summer. Thank you so much. Do you have any questions for the speaker? An interesting place with a lot of types of obsidian, Fernando, looks like a great region for study. Thank you. Well, our next speaker is not able to be here, but she has provided a video, so I'm going to play her video. Pre-recorded. The talk is titled prehistoric use of an obsidian-rich, igneous-bright deposit northwestern Patagonia. And the authors are Raven Garvey, Ramira Barberino, Augustina Rudini, Victoria Fernandez, Guadalupe Romero Villanueva, and Brandy McDonald. Hi, I'm Raven Garvey. I regret that I couldn't attend the conference in real time, but my co-authors and I really appreciate the organizer's flexibility, which has allowed us to participate nonetheless. Since I'm not there to answer questions during the event, I provide my contact information here, and would welcome any feedback or questions that you might have. My email address will appear again on the final slide of this presentation. I'm presenting some preliminary results of a collaborative project with the co-authors you see listed here. These data relate to one of our primary goals when one of the things that motivates our ongoing research in northwestern Patagonia, which is to understand prehistoric use of the region's multiple obsidian sources, one of which is a vast obsidian-rich ignombrite deposit. I'll say more about this momentarily. To orient those perhaps unfamiliar with the region, Patagonia is roughly the area indicated by the yellow ellipse here, so southernmost South America. And this talk centers on northern Neuken province, Argentina. The study area extends from the Andes, which form the border between Chile and Argentina, down through a foothills and the Piedmont of the Andes, and eventually out onto an arid plain in the eastern part of the project area. The region is correspondingly ecologically diverse on account of this vertical arrangement of habitat types and also due to dramatic differences in precipitation caused in part by the Andes themselves. This was probably first inhabited around 11,000 years ago, and throughout the Holocene was home to relatively small and highly mobile groups of hunter-gatherers who subsisted primarily on Guanaco, which is a medium-bodied camelid. This is the Mesquite and eggs of Rea, which is an ostrich-sized, flightless bird, and a variety of plants including prosopis, which is a genus of legume that also includes North American Mesquite. This of course is an absurdly simplistic sketch of the region's prehistory, but it helps to set the stage anyway. Prior to this project, I worked a bit farther north in Mendoza province, also indicated on this map. It's similar in many ways to Nuquen, the basic geography, ecology, and that caricature of human prehistory that I just described. All of these things are fairly similar between the two regions, but the two provinces are different in important ways as well. Relevant here are differences in the distribution of Napapl stone, namely obsidian. There are several known sources in southern Mendoza province, and some of them were clearly important archaeologically given the abundance of obsidian in the region's archaeological sites. But there are other Napable volcanics in the region as well, and some crystal-cryptolin silicates besides. Currently speaking, one thing that I'm quite interested in is how stone availability and tool use interact to influence technological change. So in the context of the Mendoza project, I developed a microeconomic model of toolstone procurement. Here's the basic cost-benefit structure that the model assumes with time along the x-axis divided into production time to the right of the origin, and production here includes procurement and manufacturing. Now we have use time to the left of the origin. The y-axis represents returns, which is a term left deliberately ambiguous here to be specified as appropriate to a given study. Returns could include cutting edge per unit weight, for example, calories produced by a tool's use, or even social variables like prestige if a tool was used in virtual display, for example. These are two of the most commonly occurring stone types in archaeological records are obsidian and basalt. These differ in their nabability and in the quality of tools that can be produced from them, such that in many cases obsidian will provide higher return rates. And importantly, obsidian basalt also differ in their availability on the Mendoza landscape. Generally speaking, basalts are fairly ubiquitous in the surface geology, and so they're locally available relative to most sites. So their production time is less. The production time associated with salt, basalt tools is generally lower. Obsidians on the other hand are much more patchily distributed on the Mendoza landscape. The most commonly used ones, according to archaeological records, are located in the Andes, and they're really only seasonally available. These obsidian sources tend not to coincide, the ones in the Andes anyway, tend not to coincide spatially with the most abundant food resources. So obsidian procurement generally requires special trips to these distant sources. Even these characteristics, the relationship between obsidian basalt defines a critical use time indicated by the heavy black line here, and also there on the on the x axis. Any amount of use time beyond this critical threshold, the stone forager should choose obsidian. This is represented by the red dashed line here. The use of use time that is less than this critical use time would favor the use of lower quality but but ubiquitous basalt as depicted by the blue dashed line. And in fact the model's predictions are well supported by Mendoza's archaeological record, particularly through major climatic fluctuations that triggered behavioral reorganizations, and that's demonstrated in the publications that you see here. In fact, Mendoza province is Nukin, and the distribution of obsidian is really quite different there, making it a really attractive independent test case for for this model. Lake Mendoza Nukin is tectonically active and surveys over the last two decades have identified several sources of obsidian in the study area. We started with a shaded ellipse in this figure, indicating our it's showing our current best estimate of the extent of each of these sources. Each is fairly aerially extensive. You might note the scale bar there in the lower right hand corner for reference and I'll return to this point in just a minute. The materials were collected and analyzed at the Missouri research reactors archaeometry lab. We started with extra fluorescence to determine the chemical composition of the obsidian sources in the region, and quickly realize that further analysis was necessary to better differentiate the, the, the tangle of groups in the lower right corner of plot a. So the relevant samples underwent neutron activation analysis which was better able to differentiate those sources so we now have reasonable chemical characterizations of these sources. So a slide or two ago I noted the geographic extent of the new Ken sources. And this owes largely to geomorphic processes during the Lake quaternary, including the, the formation and subsequent catastrophic failure of natural earth and dams which redistributed materials across the landscape. It's also the case that one of the most archaeologically important sources in the region is actually an extensive pyroclastic deposit containing obsidian nodules. This is the serial when will source indicated on the map by the yellow lips. And this asphalt tough is not only naturally expansive on the landscape erosion of the matrix has produced matrix has produced lag concentrations of obsidian nodules and gullies and other erosional landforms and the fluvial systems that flow through the source through flow through this tough deposit, further transport obsidian nodules downstream. As this map also indicates serial in all obsidians are distributed across multiple altitudinal zones from about 2000 meters above sea level, which are the local uplands. And really only seasonally habitable by humans, and the source extends down to about 800 or so meters above seal and sea level which is the lowlands available year round. The interaction between geographic availability of when the city and prehistoric human ecology creates this highly complex macro regional obsidian quote source scape as we call it in the paper referenced here. The serial obsidian are subangular to sub rounded and they reach about 10 centimeters along the major axis. It's mostly black but there is some variation gray and brown and brown black banded types are also fairly common. But despite this this sort of these these cosmetic differences serial and will presents a pretty low chemical variation. These samples of this obsidian show some level of translucency generally lacks inclusions and the napping quality is is pretty, pretty consistently excellent. So thinking back to this procurement model now, given the near ubiquity of when will obsidian in some parts of our study region, we would predict it's it's procurement, even at relatively low levels of tool use. We would predict it's used to the near exclusion of other types of stone, as in Mendoza nappable basalts are common in the region in no can, but given the ready availability of obsidian, and its superiority for the production of particular kinds of tools. So for anything that you might need a sharp edge for for example, there are these obsidian tools are also more easily maintained their easily resharpened. So for these reasons, the, the, the, their, their return rates are generally considered in their, and the model essentially predicts that any difference in the procurement of obsidian versus basalt will owe to their having served different purposes, whereas in Mendoza, their procurement owed more to the costs associated with going to get them finding on the landscape and obtaining them. In this case, we might assume that differences in their use would owe to something more like preferences for particular tools say obsidian for slicing and piercing tools and basalt for chopping and pounding tools. So consistent with expectations, Sarah when will obsidian dominates both stratified and surface sites, accounting for 93% of the 1000 plus obsidian artifacts considered in in the regional studies cited here. Contrary to Mendoza that the interesting question in no can becomes not when will people use non local obsidian versus local basalt but instead how were people using this local highly local immediately local obsidian, or to rephrase the question, what governs obsidian use when procurement costs are effectively removed from the equation are so minimized as to be relatively unimportant. So the stratified sites in the region provides some preliminary clues here. First is a site called Quema one will sharing its name with the source. It's indicated here with the star. The window source is is again here indicated by the ellipse that you can see that the window site is located more or less within the window source. It may be a bit hard to tell on this map but a better one is is coming in one or two slides time, but Quema rule is in the lowlands at about 1000 meters above sea level lowlands in our study region considered between anything less than about 1200 meters above sea level, considered the lowlands, the intermediate zone then being between about 1200 and 1800 meters above sea level. So going to this general model of human biogeography that guides our research in the area. The lowlands are generally considered less attractive than this intermediate zone, primarily due to the relatively lower rainfall and correspondingly lower primary biomass. The expectation characteristic of the Arab lowlands is evident in these pictures. And you may be able to make out a stream channel in the top left picture but this is a dry channel. It runs only very rarely. This site was occupied occupied intermittently between about 11,000 years ago and late prehistory so so nearing contact with Europeans as predicted by the procurement model obsidian dominates the lithic assemblage and is set on a new type accounts for almost 95% of all obsidian here, which is not at all surprising, given its location within the source region. Interestingly though there are very few courticated pieces in the record suggesting primary reduction elsewhere. The tools are also very few in this assemblage and the use of local when will obsidian is is pretty expedient these this neither is this very surprising it's consistent with the ways that local student stone is used elsewhere in the world relatively more expediently that is. This cave site, several kilometers to the northwest of que when will provides an interesting contrast here. This cave was excavated pretty recently and many of these data are preliminary, but there are nonetheless some interesting patterns emerging. The star at the top left indicates the location location of Kueva shaggy. And you can probably get a better sense here. This map is color coded to distinguish highlands and red from intermediate zone in in orange and lowlands in yellow. Now you can perhaps see better that which is just to the east of the star it's that first green dot to the east of the star is located in the lowlands whereas yaggy is is in the intermediate zone at about 1400 meters above sea level. It's also along a permanent creek. So already there are some important differences between kept quiet yaggy and when will. There will be lower elevation and also a much drier habitat. So it's being in the intermediate zone affords access to resources of the adjacent highlands which are seasonable seasonal but seasonally abundant, and the lowland resources which are available year round but generally scarcer on the landscape. This site is is the site itself the feature is quite complex with an open shelter. But there's been a lot of late Holocene erosion causing lots of of calving of the rock face itself creating you can see those very large boulder piles and the image the the line drawing on the bottom there indicates the the full extent of the feature which is about 220 square meters of covered surface it may all have been a shelter at one time but part of it now is a cave on account of of considerable rockfall. Here you can see that that there is currently very little head room inside the cave excavation was was impeded in part by this it made more difficult anyway. We excavated I should have mentioned on the previous slide, you may have noted that there is a square between what is currently shelter and what is currently cave so right at that transition we excavated a test unit. You can see its location here in what we what we take to be a relatively undisturbed part of the cave but adjacent to what is likely looters pit you may be able to make out in that top photo. We went down an arbitrary 10 centimeter levels to about 150 centimeters below surface. The table at the top of this slide provides the first radio carbon dates that we have for the site. There is a noteworthy reversal between levels three and six and also a pronounced break in the radio carbon record between about 6000 and 2000 Cal BP. This is likely an erosional unconformity that some data indicate that it is, it is probably not an abandonment of this site. I don't think I'll have time to say more about that. In this presentation below the table largely for illustration is a corresponding projectile chronology that is emerging from this study. Surprisingly, the test unit produced quite a lot of obsidian not surprising, again, given its location within the when will source consistent with data from Quavo when will that also the broader regional sample mentioned earlier, about 85% of the 400 on pieces of obsidian analyzed from the site that we analyzed by using XRF are assignable to the to the when will source. This sample of when will obsidian we selected a sub sample of 100 artifacts for a battery of tests related to obsidian hydration. I won't be able to talk about most of those tests now, but but in the context of these radio carbon dates one of our objectives is to serve probe the radio carbon anomalies that are evident here. So we selected between five and eight samples from each of the 14 excavation levels. All of them assigned to the when will sources I mentioned, Dr. Chris Stevenson of Virginia Commonwealth University performed a density analysis to estimate intrinsic water. Those data show pretty good consistency across samples and will be building on those data going forward. So the first of orators obsidian laboratory in California first measured all hydration rooms optically using a 12.5 power filar filar micrometer I piece mounted on a polarizing microscope. We then selected a 5% sample for analysis by secondary ion mass spectrometry for independent very verification rather of the optical measurements. As you can see in the top panel here that there's, there's excellent convergence or excellent correspondence between the optical and Sims measurements, which gives us a high level of confidence in the other optical measurements. So it's also worth mentioning that only three of the 100 samples showed any signs of weathering. And there were 16 total that failed to yield reliable hydration measurement for for various reasons, but there was no meaningful temporal pattern associated with these with the among these 16. The expected hydration rooms show a general correspondence between thickness and age as illustrated in the bottom panel here. As is also evident in this figure, there's a fair bit of variation in room values particularly in the more superficial excavation levels so near the surface. There's a broad data that that went into those box plots showing showing this a bit more clearly at the red line at about two and a half microns marks the median hydration room value there's no statistical significance here but it serves to illustrate that levels six and above regularly deviate from expectations with lots of rooms that are larger than expected, while level seven and below contain fewer, fewer values that are smaller than expected. This could be due to post deposition or disturbance, particularly affecting later occupations but an alternative hypothesis that we're exploring now is scavenging scavenging or later use of materials discarded during previous occupations. The whole lithics analysis for this site is ongoing so unfortunately I don't have additional data to present in this regard but the relationship between mean hydration values for each level and the degree of variation among hydration values within each level is intriguing. This is illustrated here in that in the red box on top, which shows that as mean hydration values go up. That is, as we move into these into the earlier occupations lower in the in the excavation. The coefficient of variation goes down, that is rim variables are rim values are less variable earlier in time. This could be due to post deposition or disturbance but if that's the only force responsible for this pattern. The implication is some real sort of turning of these deposits to bring those pieces with high hydration values to the surface. There really isn't evidence of this in the in the stratigraphy so again the alternative hypothesis is that it reflects routine scavenging or later use of previously deposited materials. The idea being that the opportunistic use of materials already in the cave would keep larger rimmed materials near the surface and available for subsequent selection and use, creating the pattern of greater variation and rim values later in time. So we're exploring this now and and hope to have a better sense soon of what, what best explains this pattern. So, assuming back out to more general interpretations of prehistoric use of this vast obsidian rich ignombrite called Sarah one rule. Here's a comparison between Kueva shaggy and Kueva one rule that that first site that I mentioned, also within the window source area. There are notable differences in their lithic assemblages as you can see here at Kueva shaggy there are four more formal tools particularly projectile points and scrapers. Even despite the much smaller excavated volume, whereas Kueva one rule is dominated by expedient tools and debitage. But if the pattern of hydration room values at shaggy does reflect routine scavenging of obsidian this would be consistent with a rather more casual the use of when will obsidian that we would expect given it's that it's immediately local relative to the to the shaggy site. So going to have been scavenged it has to have been discarded initially with with some remaining usable life, which becomes less and less common, the more distant sites are from sources. So in trying to understand the economics of immediately local stone use we might explore the fractal nature of the stone procurement model, or the self similarity at different scales. Before we were considering landscape level distributions of stone types. Here we might consider distributions within an area that most, I think, would consider immediately local, you know within a kilometer from from the site so if there's usable obsidian beneath your feet at Kueva shaggy. There's relatively low cost associated with procurement, you might have to root around to find a piece of the right size and shape, but there's still likely to be a level of use, you know level of need beyond which it still warrants the trip to the source for deliberate procurement of the materials that will maximize returns. With that, we we thank the many agencies and people who supported this research. And on behalf of the research team, half of whom are pictured here at Kueva shaggy. I thank you for your attention. I welcome your feedback and your questions here again as my email address on the left hand side just above the M. So, so thank you, and I'll look forward to to your feedback. Let's move along to the final paper in the this morning. We have a 12,000 year sequence of human use of the Alka obsidian source in Peru with Kurt Rademacher, David Reed, Michael Blasscock and Bruce Kaiser. Hey Kurt. Hey Nico. Can you hear me okay. Sure can. Okay, great. So today's talk is going to be a two parter. First part is I want to tell you about the Alka obsidian source. And then the second part is I want to explore the human use of this source over a long period of time over 12,000 years. So what you're looking at or the screenshot you're looking at right now is a Google Earth image of the Alka one bedrock outcrop at a mountain called Cerro Condor Siana, at about 4,800 meters above sea level.  So this is one of Peru's major obsidian sources as we heard. It's one of sort of the big three that provided lots of artifacts to, to societies throughout pre contact pre history. All three of these sources are located in the high end is above 4000 meters above sea level, and obsidians from all of these three sources were transferred extensively across the central Andes and archaeological sites that received obsidian sources are shown here in black triangles. I'm not the first person to work on Alka at all, a whole bunch of people have. And this again started with Richard Berger, he and his colleagues Frank Asaro and Mike Glasscock had identified artifacts of the Cusco site that were very numerous in the department of Cusco, east of where the source was eventually identified. But based on the spatial clustering of artifacts made from different chemical sources. Richard almost single handedly tracked down all of these bedrock outcrops throughout Peru. And one was brought that was brought to his attention was from a local townsperson who brought a big block of obsidian to cultural anthropologist working in this valley Paul Trey work with who I guess brought it to the attention of Richard. And Richard Mike Glasscock characterize that and realize that it matched the Cusco type of artifacts and so a follow up trip to the valley identified obsidian here where this red arrow is pointing. Following Richard's original publication of the source, Justin Jennings and Mike Glasscock together published on additional occurrences of obsidian in the in this valley. They identified more than one geochemical group these were called Alka X and Y. Nico trypsovich himself came here and mapped obsidian at Sarah icon, which I'll show you in just a bit. The Polish fellow Mikhail was a left ski was working in the area mostly east of here in the Valley of the volcanoes and found obsidian. He also visited the Alka Valley and collected an analyzed obsidian here with Mike Glasscock. And starting in 2004 I started working here in the Kota was he Valley, and then realized the Alka source was much bigger than than we had considered it. And he continued on trying to systematically map and characterize the Alka source till about 2015. When I first got started on this, I was started exploring east of the canyon where local towns people had informed us that there were much larger areas of obsidian, and within a pretty short walk from the town of Alka you get to see this this amazing area where I don't know if you'll be able to see my, my cursor but this talus cone here is is obsidian and volcanic ash that's raining down from the eroding. Rhyalite dome of Sarah Condor Siana. Here's in a Google aerial shot of that again. Again, this is what I showed you on the title slide, but the amount of obsidian here is enormous I've never seen anything like it. And, and large, large fragments and blocks of obsidian are eroding as bedrock, and also just appears there, it's being exfoliated from the surface by the erosion of fine material. Here's another Google Earth screenshot of a different area. This is a different Rhyalite dome that is being exfoliated, and this one's at higher elevation. This is south of Condor Siana. This one's called Navado Sappo, Havana, where a different geochemical group that we called Alka 2 is located. This one's above 5000 meters. And here's a third one called Cerro Icano, where, where the Alka 3 bedrock type is is our bedrock outcrops of the Alka 3 type are exposed here. Okay, so those are three of the Rhyalite domes with three different geochemical compositions. Those are here, Alka 1 in blue, Alka 2 in purple and Alka 3 in yellow. These are, these are clustered at the east rim of the Kota Wasi Valley, but, and these, these diamonds of different colors here are all the obsidian samples that our team has collected and analyzed throughout the years. We also found quite a lot of obsidian to the south in a different area called the Pocuncio Basin, this area here. And additional chemical groups are here as well, but Alka 1 obsidian is here, pyroclastic material, and, and then additionally, three other groups are here, Alka 4, Alka 5, and Alka 7. We originally identified a group called Alka 6, but it was within that Condorciana outcrop and not geographically different, so it was subsumed under the Alka 1 group. So in conclusion, oh, and I should mention there's pyroclastic material over here in the Andagua Valley that Mikhail Wasilevsky identified, and some up here as well. These match the, the groups that we've identified over here west of where he was working. So it seems that we have a collection of rhyolite domes. And we also have pyroclastic material that's distributed over 2000 square kilometers of this area of this area of the highlands, and it's especially exposed where erosion has has gone to work on on these, these deposits. There are six geochemically distinct subsources, and a variety of geochemical techniques differentiate them, including neutron activation analysis, wavelength and energy dispersive XRF and portable XRF. So, it took a while but neutron activation analysis is now fairly complete on all six of the Alka subsources. That's the plot in the upper left. In the lower right, portable XRF can also distinguish these same Alka subsources using the same samples and then all of the other samples that we've collected. When I started doing this, it was really an iterative process of exploring mapping obsidian coming back to the lab geochemically characterizing it and then going back to the field, trying to trying to make some sense of the patterns. Since I started doing this work. There's been some improvements in the bedrock mapping that's available in Peru. And when I we plot the two areas where obsidian is most common. We bring up some of the new geologic mapping we see that the obsidian clusters very beautifully in a couple of map formations. Obsidian is occurring outside of these formations. I believe it's because the geologic mapping is is a bit imprecise. So these formations are are referred to as the Senca or Arma formations and the terminology is Sean club through a has done some great work in this area that have has constrained the Alka of the deposits that seem to contain Alka obsidian to between 3.7 and 1.5 million years ago. Okay, what about human use of the Alka source. The source is actually local at a site called concha rock shelter. And here's a photo of the landscape that contains concha rock shelter it's right there in the cocoon show basin where all of this Alka obsidian is located. And in fact obsidian is available on the alluvial fan directly below the rock shelter, as well as in the in the basin as pyroclastic material. This is really remarkable for a lot of reasons I won't go into. But one of the ways that we've used it is that it has an amazing sequence intact sequence of stone tools, and because it's local to the Alka source and it has so many stone tools obsidian over. Over 1100 obsidian formal tools that we've analyzed, we can examine these of these, the pattern of use of obsidian through time. We don't have a sequence here, no site in this area is continuously occupied. We have sort of these windows in prehistory, and those are goes go back to about 12,000 years ago in the terminal Pleistocene, about 9000 years ago in the early Holocene, and about 6000 years ago in the late middle Holocene, and then within the last 4000 years or so. I just want to walk you through what those major patterns are showing. And I'm only going to talk about projectile points and these next four slides. I'm setting aside other kinds of stone tools made of obsidian projectile points are numerous and they tell a pretty neat story. So here we are at the terminal Pleistocene use of the Alka source here at Conchaica rock shelter. We see the presence of all of the obsidians that occur within the Pocuncio basin so these are all local obsidians that could be foraged within the normal day to sustain food and other resources around the Conchaica rock shelter. But we also see a predominance of the Alka for obsidian subsource and the Alka for subsources here located some distance. Why are why is more obsidian made from this more low more distant source was we've seen in some other talks today. We have obsidian here that this is a bedrock outcrop so the size of the obsidians larger, it's there in more, more quantity, and you can make anything you want out of it as long as you're willing to go for a walk. So it seems that that was worth it for these folks. I've seen it shifts a little bit. So the major shift is that we see a great increase in the amount of Alka one. Now I'll go one does occur locally in the basin and it has been used previously in the terminal Pleistocene. But I can't explain it's it's increased in this amount in any other way other than I think these people have discovered by this time condor say on a bedrock outcrop up here to the north. And that's the reason I can think of why there why the obsidian and what this type would increase. If that's true. It would imply a 66 kilometer round trip mostly above 5000 meters above sea level to go and obtain that material. In the late Middle Holocene. We see another interesting evolution, where the locally foraged obsidians the Alka five, the Alka seven those drop out. And now we see exclusive use of both bedrock outcrops, Alka one and Alka four, and that pattern only remains the same and maybe a strengthen in the late Holocene. Within the last 4000 years, where we see near exclusive exclusive use of those, but especially focusing in on this Alka one outcrop which is the biggest outcrop of all in the whole region. The size of obsidian and the quality is amazing as well. Okay, so that's the local story, but we also have this kind of interesting non local story right from the start, the Pocuncho basin on this on the plateau where I've been telling you about concha is the source of these obsidians the only place where these three obsidians are together, but obsidian also occurs almost at the same time at the coast about 150 kilometers away at a site called Gibraltar Hagwai. And Gibraltar Hagwai was originally thought to date to about 13,000 years ago, predating concha rock shelter in the highlands, and is often used to suggest that perhaps there was a coastal migration first, and that people moved into the afterwards. Work by our team has showed has shown that the coastal site is actually not earlier than the highland site. In fact, it might be a bit later, or we can't tell them apart. Maybe there are different groups of people living in each area, but at any rate, Alka obsidian has come down to the coast, right from the start at this site Gibraltar Hagwai. And it's coming down in various sub sources. West of Cape Rata Hagwai 42 additional sites at a place called Papa Colorado show a sustained presence of Alka obsidian throughout throughout the early and middle Holocene to about 5500 years ago. In fact, most of the the formal tools at this coastal area, even though there are local materials raw materials that are suitable. Most of the materials used for stone tools in this area are obsidian, and they come from the Alka source, Alka for Alka one Alka five and Alka seven all come down to Papa Colorado with the closest Alka subsource Alka for this one here, comprising the majority of the of the stone tools. These are these are patterns that hunter gatherers are responsible for, but we can come even more, even closer to now. And let's look at the end of the pre ceramic period this is pre pottery, and into the beginning of complex societies in the Andean region. This is also a time period when we see domestic camelids coming on the scene and Yama caravan starting up maybe. And if we look at the distribution of obsidian and Peru we see that that Alka one obsidian becomes quite widespread. It goes far beyond its source region. It's transferred over about 1000 kilometers up here to northern Peru at this time. This is before any state society is around. If we look at the early horizon when when we see some early complexity appearing we see even more of this pattern, where we start to see other Alka subsources going away from the source region such as Alka five. This is the middle horizon. This is the period where the Wari Empire is expanding and the Wari Empire is really interesting on this time period the middle horizon is very interesting in the Andes because this is when obsidian distribution really goes really goes haywire. Obsidian is going all over the place from all kinds of sources. And so we can look at how Alka figures into this by looking at this little area in the red box that my co-author here has has done a really interesting study. So this is the area called the Mahes Valley which is just to the south of the Alka source. And in this area. David has excavated two kinds of sites. One are sites that the Wari state seem to be responsible for their really complex sites, lots of architecture and very distinctive architecture that relates to the Wari specifically. And then there are these local caravan way stations. These are simpler sites that appear to not have so much of a Wari administrative footprint in them. And David analyzing over 300 artifacts of obsidian here has also and also the Alka subsource geologic material has been able to look at the different use patterns in obsidian here. So the Wari state sites have almost have an exclusive use of the two bedrock outcrops from the plateau, the local bedrock outcrops. The caravan way stations have this amazingly, a much more diverse obsidian profile with local material still comprising the majority of what's here. But material from very far away from a whole bunch of different sites in central and northern north central Peru are appearing here as well. And David thinks this is because long distance Yama caravans are coming in and bringing all of this obsidian to these sites. Going finally ending with the late horizons is Inca times when when people are really, really familiar with, with Peru. We, we continue to see Alka subsources moving away, including to a site called Yama Wilka that that Steve Shackley published on. So it's an interesting story of Alka subsources and, and, and analysis of larger artifacts sets by portable x-ray fluorescence is part of what's allowed us to see with this increased resolution, the, the evolution of behaviors, starting from the long distance gathers and long distance social connections, then moving probably to Yama caravans carrying obsidian far and wide along and across the Andes. And finally, states getting involved and seeing a very different kind of pattern when states are involved in the distribution of obsidians versus what when those states are not involved. And I just want to thank everybody for setting up this meeting and for inviting our team to present our work to you. Thank you Kurt over 10 minutes over time but we're going into the lunch now so we can presumably chat with Kurt and those of you who go to lunch will be resuming at 1pm Pacific time. So, I'd like to ask you a question Kurt. Is that data from my head is that in David dissertation. Is that available. Yes David, David, are you here. He was here. Yeah, there he is. Yeah, yeah, so that's in the dissertation soon to be submitted for publication. Thanks for sharing that here. So that's great that you're able to, to pick apart the different uses with all the sub sources. That's really interesting. And most of the Indian sources don't seem to at least central and he's done seem to have so many sub sources. I don't know why that is. I'm somebody who's smarter than me needs to speak up but maybe I, yeah, I don't know why that would be but it is interesting. I mean, the Yelma Erkins did work at the COSA source looking at the, you know, usefulness of sub sources and to archaeology to investigations and, you know, I wonder if maybe at Alka there was there was a series of extrusion events, you know, and Thorez data might answer some of that like how the timing works out for the different sub sources. So great, great papers. I actually had a question I was chatting with Dave about earlier and so maybe Richard and Kurt might help clear this up. Dave was telling me there's a bit of an overlap in at least PXRF values for Chiranya and Alka five. And I'm just wondering without higher resolution techniques, how we, how we might deal with that. Because I know especially in the region we're working in we're right between the two Alka comes in, mostly Alka one I guess we get a little bit about the five to I guess right Dave. Anyway, I'm wondering how much overlap there is between the two sources and what we might look at besides going to higher resolution techniques to differentiate them. Yeah, that's a great point. Ryan, recently, I had some information I studied an artifact set from a place called Hake Nasa cave in northern Chile. And I was pretty sure there was an Alka obsidian artifact there. I didn't know about the Chiranya source then. And, and I, and, but I noticed that it was, it was close to Alka one and I thought, oh, I, we've got to, we've got to go to neutron activation analysis on this. And I think, yeah, that might, that might be necessary in some of these cases but I actually asked my class cock, you know, he's the Dean of these things about how to do it, you know exactly your question. And he said that he couldn't figure out at the moment how to do it, except by using neutron activation. So, you know, what he suggested was that, you know, if there are these instances of ambiguities that a once you just take the time and effort to get it run by neutron activation. Of course, knowing Peru's export laws. It sounds easier to him than it does to someone like you or me, or Kurt, but, but that may be necessary. Who knows, maybe if, you know, if broker keeps improving the quality of this machine and it'll eventually allow us to get at the elements that the neutron activation is, is using now. But I can send you his response on that I have it in the email. So those six samples Richard that you analyze that you assigned to Toronto from Omo are via neutron activation. Yes, they're all via new track. And they were from Paul Goldstein's excavations. But you know, one of the interesting things is the difference between Omo and, you know, a serial vowel, you know, it says stark, you know, they're so close and yet it's a different. It shows the power of the state. Yeah, it does really. I mean we have hundreds and hundreds of city and artifacts and I think, well, Dave can speak more broadly that she's been working with Paul on analyzing everything else and T when Aku and the valley from XRF perspectives. But the difference in quantity is vast and the difference in the type of material. I was talking about Omo, I wanted to ask Richard. Do you think that the presence of Chiranya at Omo was maybe because she by wasn't accessible at some time, perhaps because of worry. No, because, you know, the, the chivay is. It's so common at T when Aku is 77% of the obsidian. So I think it has to do with sort of the, the internal social dynamics of the to be cock a drainage that the people in Omo must have had some social ties to this sort of God forsaken area. And where Chiranya is located, you know, it's a very provincial very local and rather than going to T when Aku and acquiring it through that source, Omo was instead calling in these kinship or, you know, fictive kinship, or other kinds of ties or or or caravans from that area. Everywhere else seems to, you know, you look at, you know, we ran really a large sample from the rest of the TV cock a base and, and I have a big set also that I did with chip Spanish I haven't we haven't published it yet, in part because it's so boring it's all chivay. You know, but none of the none of it showed the Chiranya signature. So, really, the, the that that source is just staying in the southern TV cock a base and, and with the exception of going to T when Aku or to Omo. And that's probably for different reasons. The route from the coast is is pretty nice like up to Utah near Erika. That's a possible route to Omo as well. Right now there's no trouble in getting to Omo. It's kind of in the works with Paul right now but some of the PXRF data of some of the smaller debitage from Omo is also picking up a lot of the smaller sources. So, potentially even anio and other some alco sub sources. Yeah, so, well, let's hear more about that in the future. But yeah, I think there's a lot of interesting stuff happening in Motegua drawing in a lot of different variable sources. Did you say there's a neo at Omo? Yeah. I guess I got to hold that site. Yeah. This is our, this is the Indianist session here. Is there any other any of these questions. Well, the other thing about Sharanya or about Kamuku is that it's so close to Akunkawa but it must, that must be pretty lousy obsidian because it doesn't go anywhere and they don't even use it at Calcutani, right? Even the people who are sort of sitting on it would rather go and get Sharanya. But yeah, the other one we're closing in on is, you know, in that article with Karen and Sarah here we talk about this Choombi Vilkas type. We came, someone found a source in the Choombi Vilkas area that we thought must be it because it was in exactly the right spot. But when we ran it by neutron activation, there were small differences between the source samples and the artifacts and we re-ran the artifacts from that old 2000 article. So now because of the pandemic, they were unable to go back. But my class got things that probably the actual source that was quarried is probably very close to where those source samples have been taken and so hopefully we can get that one out of the way I'm trying to knock these rare types off. But if you're in Choombi Vilkas, go look for it. You mentioned the Makusani being really unusual in appearance, but it's, is it very good for toolmaking? My sense from Nathan's article was that it wasn't that great for mapping that was just aesthetically interesting. Exactly. I think it was mainly that it's cool looking. Yeah. I don't know how much the visual qualities of obsidian affected the choices in the central Andes. Other parts of the world, it was very, very important. In central Andes, you know, you don't, for example, in QCC, you have all that sort of blood red, that dark red obsidian and, you know, you'd think that would have stimulated some sort of special attention or, but it's just mixed in, you know, with the other stuff. Not like the particular obsidian in Mexico. We found one good point at QCC said that had a, the red was on the tip and the rest was black as if they had mapped it to look like it had blood on it. Really? That was pretty neat. You should publish that. A book cover. Yeah. So I got a follow up question for Kurt and Dave about, I'm sorry, I'm going to keep on the worry stuff just because that's my passion, right. So what do you guys, I mean, so Dave stuff is pretty interesting in that specialization of the certain subsources. Are you guys still thinking though that these are still that there's no real like, kind of, I don't want to call it industrialized but, you know, worry kind of exclusive access to certain sources or industrialized kind of extraction at certain sources, like alcohol one, or do you really don't see any evidence of that on the ground is such a broad and expansive source that they're not going to be able to really control access to it and so we're never going to be able to understand that kind of perspective on how worry is interfacing with those sources. That was Donna by the way hitting me for going on too long. Hi Donna. Hey Donna. Yeah, it's, it's interesting right Justin Justin Jennings went to the Kota Wasi Valley to look for evidence of control of the Alka source, and then didn't find it. But, but now we know the Alka source, you know the action really isn't in the Kota Wasi Valley. It's above it. So, so if the if the sources way up on the plateau, you know there are no towns up there that are big and there are no massive installations. And I don't know I'm just spitballing here but it seems that one of the if you wanted to control it you would need to control the transport of it, not control the outcrop itself. And, and so you'd look, you'd look for installations in the in surrounding valleys along routes that lead away from the source to other places that are useful to take it. And, and maybe Dave's, Dave's, you know, found some of those in one of the principal routes and we probably need to look at others but I'll stop there. So just from the, the worry. State Center in the mahes that was the focus of my dissertation. I think it's more direct procurement. It's so much Alka one. And whereas the surrounding kind of local settlements have very, you know, makes a different long distance and local sources. I'm not too sure about control. I mean it's just such an expansive area. But yeah I think it is that was focused on trade routes. You know, might factor into it but the same time the locals have, you know, a lot of, you know, a lot of different forms and varieties so I really don't see any control except for cannot direct procurement maybe by by worry and it's going up to the major bedrock sources. Yeah, I mean I gave some thought to this, you know, in relationship to key species source but it's the same is, is just you know when people talk, you know, long ago about these different states controlling obsidian sources. And I think in their mind they were thinking of something closer to the South African diamond mines or the, or the Inca gold mines, you know, where you have very specific spots that you can actually control but all the major sources in the area are huge, you know what you said 2000 square kilometers or I mean it's gigantic I don't see how anything I mean we can't control our own border right and it's it's nothing like that so I'm why they could do that in history but on on, you know, the Wari Road system has never really been fully studied and one can imagine that there are various points along a highway system whether it Inca or Wari whatever that you could close off movement and and prevent the sort of long distance transport of obsidian that has been, you know, been authorized by the by the state so I think the highway system is a place to look if we're interested in in state intervention in the movement of the of the volcanic last. Yeah that was exactly what Dave's dissertation tackled so at least for the. I look forward to reading it. So go read it. I look forward to seeing it. It's not done yet right. I think it's interesting to see that this is because in the case of the by the Cusco, like, no in the Cusco valley, you could see all the sides, the main importance, the middle horizon sides. They show up this Chi Chi by source, you know, so the Chi by sources very important for this middle horizon sites controlled by the wise. So how they get there in because because including in Piki Yachta or New York will be I the source of the obsidian is Chi by so like Richard said, and we will agree that it's important to find the road, the water road, you know, to go to the bio Cusco or the agreement valley will be the next one to look like an area where they were going through to Cusco, which road they were choosing, you know, if it was one principle road like it in case we have secondary roads. It will be nice. I really would like to see you. David read. Yeah. Yeah, I defended in December so I can email it to those interested. Is it a Chicago circle. You I see. Yes. We used to be Chicago circle. We don't go by that anymore but I'm not. Yeah, I always confuse this is Chicago circle. Yeah. We're showing our East Coast, do you know. I will go to just a city and exchange question middle horizon. Dumbarton Oaks is sponsoring a workshop next weekend. And Mary Glacky gave it a nice paper on the worry sites of Cusco and specifically talks about. I mean from rock G where Bill Siller has been working down through our and Piki Yachta and, and down on further than that, there is there's a very interesting corridor of worry movement. That, that, that might. Hmm. Your question and calm. It's very interesting. I was excavating three weeks and Piki Yachta as a volunteer. So I got very interesting on that. You know, it's a new offering that they have found. The one, the same as a Reola is a new offering is so beautiful. The same figurines. Going to be another one just like that. Yeah. Heather like I run some of the XRF for Heather like man and I were preparing. For me. Give it to you guys after me. After the pandemic. Yeah, there is very eager to finish that job. So one thing I wanted to mention is I've been analyzing some stuff for Axl Nielsen from Northwest Argentina. And they have really high of rubidium over, over 1000 and some or over 700 parts per million.  One of them is moot is not the sunny. So it's useful for calibrating, or you can use one of these missed samples, but, but it's something relevant to the, to the andy's only I think is, is that we have these super high rubidium values if you do any work further south you'll run into this issue. And the 40 sample set from her doesn't go high enough for the rubidium down there or my Chris on it for that matter. And Mike only has one piece of my Chris on it from Nathan Craig so anybody's in I have beauty and has a few days to kill. If you can get some more Chris on it. Nico I've got, I've got about 12 sitting in my office. Mike would like some, I'll send it to me might with glacial geologic work over there and, and we just found it. And I mean we knew, we knew from Nathan Craig's work that it was over there but so that's why we knew what it was, but we never we've never done anything with it. Well, yeah, it's good for that upper end of rubidium then for, you know, raising the range of your calibrated results. Cool. We've actually found some artifacts of it too but really, it's almost cast to it. Sort of greenish clear. Yeah, I'll send them to I'll send them to him. Perfect. You know, Nico and also I'd like to also just throw in a pitch if people are looking for permanent repositories of raw material. The Field Museum has started a raw material collection of volcanics and in fact it's a big geoarcheological kind of a geoarcheological materials collection. And so, we're willing for long term to take on curation and then loaning that out to anybody who needs it. So, I know that people have a lot of collections that are wondering what they might do with their permanent raw material collections. So will the University of Chicago be there for a long time. We hope so. It's actually a field it's a field museum so we're actually an independent institution. That's better. That's better. Well, I can I just have a paper coming out in geoarcheology on the Rio Grande second you put secondary deposit study and, and, you know, I talked about, I don't know if you're on Ryan but the East scholarship.org that we have at University of California. And that one of the reviewers, it was anonymous I don't know who it was was saying well I don't know if that's very permanent you know you should keep it with Wiley publishers and I go, why did what somebody might buy Wiley publishers tomorrow and it could disappear you know I think the University of California probably be there for a little bit longer. That is one argument I didn't want. So we still have to launch our, our labs official webpage that will make public all of the results performed through the field museums elemental analysis facility, but all the data is being archived on the museum's enterprise database system, which also houses all the information for the museum's objects. Yeah, good idea to lose that. And so that means they can't afford to lose the data from the. That's great. I mean one thing I was when I was working with Steve on these reports we were trying to get the results, the part per million in a table format, so that, you know it's like a CSV file attached to the PDF. So you don't have to try to even have to retype it. I didn't do that. Yeah, I didn't do that through 2016 but I'm working on all of all of them through now, and I'll have a separate and attached CSV file to that. Yeah, that's a lot better. So I still need to talk to you about doing batch uploads. Okay. Well as long as the University of California keeps my pension coming. In New Mexico than the area. You can't believe it. Yeah, yeah. You're one of the many reasons I'm here. Well, Mike, harking back to your call about kind of centralizing some of the data and it might be interesting to think about how these different enterprise systems that are holding data can be linked together and be perhaps drawn up on I mean I know from this kind of work we are, we're on an enterprise database system that we can link to the other museums like the American Museum and so theoretically you could set up a web server that would dive into that database and pull out whatever you wanted from it, and if it could dive into multiple databases, you would actually allow people to maintain their independent databases for archiving their data, but have a central authority or a central portal for going on and searching and getting that's kind of an interesting per