The Earth, Inside and Out


1. How do they know about the layers in the earth – the core and the mantle, etc.

When we check earthquake activity we can see how the ‘push’ waves and ‘shove’ waves go through the earth and that tells us a lot about what the layers in the earth are, and whether they are fluid or solid. The different layers of the earth respond differently to the different waves.

earthquake waves


2. Is the earth continuously getting bigger?

No, not really.  We expanded that one time at the time of Peleg which caused the Atlantic Rift and formed the Atlantic Ocean, and that finished it.

3. How can you tell how hot it is in the earth’s core?

We know how deep it is, so we know the approximate pressure.  We know the central core is liquid.  For it to be liquid under those pressures, the temperature has to be at least 7000 degrees F.

4. What would happen if the ocean leaked into the mantle?

The pressure coming from deep in the earth pushes things up, which is why we have volcanoes and geysers.  That kind of pressure does not allow the oceans’ water to go down.

5. Is the mantle the same distance all the way around?

The mantle is approximately the same thickness all the way around the world.  However there are places where it is not so far down, such as at the bottom of the ocean.

6. Are there only water molecules in the mantle?

Water was driven out of the mantle due to the heating of the interior of the earth, but water was not all there was then and is not now all there is. The mantle is made up of a number of minerals, primarily silicates of various sorts (a silicate is a mineral which is a combination of silica and other elements, such as magnesium, calcium, sodium, aluminum, etc.). Each of the silicates has its own crystal structure which can incorporate water molecules into it. That is the water that can be driven out by heat. The water is found in the interlayer spaces of the crystals.

crystal molecule


7. Could rivers be made out of the sea?

Rivers flow downhill into the sea.  If the sea were higher than the rivers, it would not be the sea anymore but would drain away into another, lower basin that would then become the sea.

8. After thousands of years is water still coming up?

Yes.  We can see this in geysers and springs.

9. Why does the water under the crust become smoky and black?

You are thinking of black smokers, not  water under the crust itself.  When the black smokers come up in the ocean floors, they bring up a lot of minerals which make the water appear very dark.

black smokers

10. When water moves, does it take pieces of rock with it?

It depends on how fast the water is moving. Slow moving water carries very little with it. The only time it will carry a lot of sediment is when its tributaries (streams and rivers feeding into it) have increased THEIR contributions of muddy water due to rain storms or spring melts. On the other hand, rapidly moving water can carry quite a bit with it, and the more rapidly the water is moving, the larger the stones it can carry with it.

slow water fast water


11. Before the earth, were all the continents one supercontinent?

Before the earth, there is no possibility of continents of any sort, as there would have been no earth for them to be on. However, on the early earth yes, all the continents were part of one supercontinent.

12. In Pangea, where would Alaska be?

Here is an idea of what Pangea looked like. In this one, you can see the beginning of Alaska at the top left of the North America section. (The rivers it shows are current rivers, which actually make no sense on that map, but at least the idea of where Alaska may have started out is there)




13. How big was the beginning continent? Before the continents split, did they take up the whole earth or just on one side?

Just one side. Rough estimates put the original continent at about one-third of the earth’s surface. The earth’s surface today covers about 509 million square miles. We know Pangea stretched from north to south almost from the North Pole to the South Pole so that’s about 12,000 miles long. That would make the average width of the original continent about 14,000 miles wide. But it was not a rectangle or oval, it probably looked more like this:



14. How were the continents held together?

When the land rose, it rose as one mass.  It split later.

15. What are the lands in between the continents?

I think you are referring to what we think of as depositional areas. The main continent structures are giant basalt and granite uplifts and the areas around them which are land are materials originally washed off of them, which form the sedimentary layers and lowlands.

16. Why are the oceans’ names different when you talked about Pangea?

The bodies of water were named by scientists who recognized the earth was much different then than it is now, so they named the bodies of water separately.

17. What is the significance of the dykes?

The dykes in Pangea show where there were weakened spots in the earth’s crust where was water was coming up. The drawing below only shows the southern half of Pangea.

Pangea dykes


18. Did the tectonic plates exist before the continents separated?

Yes, and we are aware that there were weakened areas of the crust between them. The dykes were located in those areas.

19. If we were still one continent, could we drive from Oregon to China?

Very possibly, yes.

20. If the Atlantic is still splitting, will we eventually connect with China?

It would take awhile.  The separation rate right now is about an inch a year.

21. Was the earth formed with molten lava when God created the universe?

No. Molten lava is the result of melted rocks. So the rocks had to be there first. Evidence from rocks and zircon crystals show that the earth started off cool and watery on the surface, just as the Bible indicates.

22. How did we discover the early earth had oceans, water and rain?

First of all, the Bible has long told us that. But science is still gradually coming to that conclusion. There are two strong pieces of evidence: first that our earliest rocks are “metamorphic.” That means they were first formed by water depositing sediments that got compacted down. Then either due to more pressure, or heat, or both, the rocks were changed and became much harder. Metamorphic rocks are ALWAYS formed by water first, before they are changed. The second piece of evidence is from something called zircon crystals. Many times crystals will form around something else. The bits of ‘something else’ are called ‘inclusions.’ A number of very, very ancient zircon crystals from the Jack Hills in Australia have a type of oxygen in them that only is present in water, and it often has to be the result of running water, so that extra air will be included. Quiet water doesn’t have much free oxygen in it at all. Running water means there was a hydrologic cycle even at the beginning, with enough rain to cause streams to flow into the seas.

23. What is a continental shelf?

A continental shelf is an area next to the land which is relatively shallow (generally less than 500 feet deep).

continental shelf.

24. Would the continental shelf fall into the water?

As you can see from the illustration, some of the sediments making up any continental shelf can, and often do, slide down onto the ocean floor. However as the rivers deposit more sediments when they empty into the oceans, and as storm drainage washes down into the oceans, the material making up the continental shelves is replaced. Some continental shelves are so wide that what they lose into the ocean floor is quite small compared with their size. You can see that from the lower picture which shows the size of the continental shelves.

25. How long are most continental shelves? How deep can a continental shelf be?

Wikipedia has an excellent answer for you on this one:

“The width of the continental shelf varies considerably – it is not uncommon for an area to have virtually no shelf at all, particularly where the forward edge of an advancing oceanic plate dives beneath continental crust in an offshore subduction zone such as off the coast of Chile or the west coast of Sumatra. The largest shelf – the Siberian Shelf in the Arctic Ocean – stretches to 1,500 kilometers (930 mi) in width. The South China Sea lies over another extensive area of continental shelf, the Sunda Shelf, which joins Borneo, Sumatra, and Java to the Asian mainland. Other familiar bodies of water that overlie continental shelves are the North Sea and the Persian Gulf. The average width of continental shelves is about 80 km (50 mi). The depth of the shelf also varies, but is generally limited to water shallower than 150 m (490 ft).The slope of the shelf is usually quite low, on the order of 0.5°; vertical relief is also minimal, at less than 20 m (66 ft)."

Although we are not positive about the measurements of every continental shelf, this map gives a pretty good indication of the way they surround the continents:

continental shelves


26. What is a reef?  Where can we find them on earth?

A reef is a layer of marine organisms that builds up over time. Sponges can build reefs, and so can coral. Here is a good picture of a combination – the green are the sponges growing in a coral reef. The reef here is made up of both kinds of organisms:



The most famous reef system is to the northeast of Australia, and is called the Great Barrier Reef.  It extends all the way up to Papua New Guinea.  It is here many ships were shipwrecked in the times of early explorations.  It is a very dangerous area for divers and ships.



Great Barrier Reef1 Great Barrier Reef2


Here is one of the ancient ships that was wrecked trying to navigate through the Great Barrier Reef



27. How does a sponge reef get upside down if it grows upright?

Tsunamis can tear up reefs and turn them over and break them up. Severe storms can also do that kind of damage.

28. How long did it take to form a reef?

A sponge reef today grows at about 3 inches a year. A coral reef grows at about the same rate. There is some good reason, however, to think both types grew somewhat faster in the past and possibly larger. It still would have taken a number of years, however, for a good-size reef to be established.

29. How long across is the equator?

The equator stretches around the middle of the earth. It is 24,901 miles around.. 

30. Could the earth explode?

Not from the forces presently within it. Our radioactive heating has slowed way down since the beginning and so the pressure under the crust has been vastly reduced.

31. Why is everything found in Australia?

Most certainly everything is NOT found in Australia! However, because Barry is from Australia and did a lot of geological research there, he is very familiar with the evidence that exists there. 

32. Do earthquakes cause tsunamis?

Yes, they can, if they are under the ocean and displace a significant amount of ocean floor or ocean ledge in one of the canyons.

33. Is there any tillite in the Oregon caves or anywhere near us?

No.  Our area was underwater then. The closest examples of tillite from that time are in Death Valley, California. That area did not sink down underwater until after the Flood, when the earth was settling. It was raised up again at the time of Peleg, when the continents were divided and the whole series of mountains in the West were ‘wrinkled’ up. (“Diamictite” is the same as “tillite.”)

Death Valley


34. How did the West Coast get there if it wasn’t there before?

When the continents began dividing, the gap between them widened at the Atlantic Ocean.  This caused the other sides of the continents, both in Asia and the Americas, to “wrinkle up” and a lot of land was uplifted as a result.  That is what formed the entire west coast of North and South America.

western hemisphere