shows differences in elevation

Topographic Map differs from regular map


the difference in elevation between two points


true or false, index contours are not actual contour lines

Ratio scale used for larger numbers

difference between ratio scale and fractional scale

magnetic declination

caused by a slight misalignment between the Earth's rotational axis and the global magnetic field


true or false: magnetic declination does not change over time at a given location

quadrant bearing

expressed as degrees east or west of true north or south (with respect to)

azimuth bearing

expressed in degrees between 0 and 360 (N 0 or 360, E 90, S 180, W 270)


the slope of a stream along a selected segment

base level

the lowest level to which a stream can theoretically erode


the rate of stream flow at a given time and location


the amount of material transported by a stream

oxbow lake

formed when the outer edge of a meander is cut off

yazoo tributary

formed when a tributary cannot breach a river's levee, and flows parallel to the river


created when the water velocity decreases dramatically, such as when entering a lake, ocean or dry basin


channel pattern that occurs where rocks are fractured or faulted in two main directions that are perpendicular


channel pattern that develops on flat lying or homogenous rocks

drainage basin

the area of land that is drained by one stream

oxbow lake

crescent shaped lake (like a half moon)

point bar

the inside point of a river pointing to the direction the river turned

cut bank

the outside point of a river where it turns directions


the direction of a line formed by the intersection of the surface of an inclined rock layer and a horizontal plane


the angle between a horizontal plane and the inclined (tilted) stratum, fault or fracture

normal fault

fault that results from the hanging wall moving down with respect to the footwall (footwall doesn't move)
-caused by tension

reverse fault

fault which results from the hanging wall moving up with respect to the footwall (footwall doesn't move)
-caused by compression (rock shortening)

strike-slip fault

fault that results from the horizontal movement along the fault plane (vertical fault plane)
-caused by shear and involve motions of rocks

block diagram

a combination of the geologic map and two cross sections; small 3D model of a portion of earth's crust

hanging wall

the top surface of the fault


the bottom surface of the fault

boundaries between plates (oceanic and continental)

where most earthquakes occur


limbs dip away from center (hinge); oldest rocks are in the middle, youngest on the outside


limps dip toward the hinge (center); oldest rocks are on the outside, youngest on the inside


underground origin of the earthquake, in bedrock


the point of earth's surface directly above the focus

Richter scale

logarithmic scale, uses actual numbers

Mercalli scale

scale that is a set of definitions based upon what people in the area feel

P waves

the fastest waves

L waves

the slowest waves; cause most of the generally recongnizable earthquake surface effects

S - P time interval

the time it takes for the secondary waves of an earthquake to hit after the primary waves hit


the amount of seismographs needed to determine the exact location of an earthquake





P wave

moves up and down continuously

S wave

moves up and down and also in a slinky motion

L wave

huge waves

rocky coasts

ocean waves strike shores with immense energy

soft sediment coasts

eroded much more easily on a human scale, but slower on a geologic scale

wave energy

builds as it reaches the shoreline; intersects at oblique angles

longshore drift

the movement of sedimentary materials along the coast created by swash and backwash
-flow parallel to the coastline and move vast amounts of sedimentary material

beach budget

the amount of sedimentary material carried to and removed from the beach



rip currents

form at right angles to the shoreline and carry material out to deeper water


moves material a minor amount


bring sediments to the beach usually the same amount as removed (no gain or loss)

terrigenous sediments

the most significant supply of new material entering the beach budget
-sediments from land surface carried by river to the coast

coastal control

a continuous project, seawalls can damage beaches and hurt the turtles because they try to clim up the walls when laying eggs and fall over and get stuck on their backs

parts of a coastline

barrier island, estuary, headland, longshore current, marine terrace, sea stack, spit, hook, wave-cut cliff

barrier island

a long, narrow deposit of sand, parallel to the coast and raised above sea level, by the action of waves
-formed by either sand dunes drowned by rising sea level, or spits and bars formed by the refraction of waves


part of the sea where saltwater is mixed with freshwater, often in a drowned river valley


projection into the sea, usually by land underlain by rock resistant to erosion (generally associated with uplifted coasts)

longshore current

a current in the near shore surf zone created by the action of wind and waves

marine terrance

a flat surface eroded by the action of waves that is often uplifted and exposed above sea level on coasts that have been tectonically uplifted

sea stack

a pinnacle of rock isolated from the coast by the erosion of a headland


a long, narrow stretch of sand deposited by longshore drift and longshore currents when the land ends at a bay


a spit that is turned inward at its outermost end by the action of currents, waves, and tides

wave-cut cliff

a steep cliff facing the ocean that has been cut by the ocean


a structure built to protect an offshore area, such as a harbor, from the action of waves


a structure build to protect a portion of th eshore from loss of sand and to prevent erosion


a structure erected to retain current velocity in channels and entrances to harbors in order to diminish siltation of the filling in of the channel by sediments


a structure erected at the shore to stop erosion or extend the shore


if a seismogram's first motion is upwards, is the block on with the seismograph is attached undergoing compression or dilation?

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