Coker Earth science unit 7

Question 1

What is the law of Original horizontally?

Answer 1

All sedimentary rock layers and some extrusive igneous rocks are originally deposited in horizontal layers

Question 2

What is the law of superposition?

Answer 2

In undisturbed rock, the layers on the bottom are older than the layers on top

Question 3

What is the law of disturbed rock strata?

Answer 3

Any process which disturbs the rock must be younger than the rock it disturbs

Question 4

What is the law of crosscutting?

Answer 4

Any feature that cuts across layers of rock must be younger than all the layers it cuts across

Question 5

What is stratigraphy?

Answer 5

A branch of geology dealing with rock layers (strata) and the sequence of events that created them.
Basically the laws

Question 6

What is uniformitarianism?

Answer 6

The idea that the same geologic processes we see at work today, have occurred in the past

Question 7

What is relative dating?

Answer 7

The age of something compared to something else

Question 8

What is tilting?

Answer 8

A type of disturbance that tilts rock layers. Caused by plate movements

Question 9

What is folding?

Answer 9

A type of disturbance that folds rock layers. Caused by plate movement

Question 10

What is a fault?

Answer 10

A fracture in the crust along which the lithosphere moves. Caused by plate movement. It displaces rock units

Question 11

What is an intrusion?

Answer 11

Magma that cuts unto rock layers and cools below earth’s surface forming igneous rocks. Caused by rising magma. It cuts through existing rock and contact metamorphism of existing rock

Question 12

What is a dike?

Answer 12

Igneous rock intrudes along fractures in the existing rock. It could be vertical or horizontal

Question 13

What is a sill?

Answer 13

Igneous rock intrudes along sedimentary layers and is horizontal

Question 14

What is a batholith?

Answer 14

The large mass of igneous rock with irregular shape

Question 15

What is inclusion?

Answer 15

Parent rock breaks off into magma and does not melt and is found in the cooled igneous rock

Question 16

What us extrusion?

Answer 16

Molten rock that reaches Earth’s surface (lava) and cools forming igneous rock. Caused by rising magma that reaches the surface. It creates a horizontal layer on top of the existing rock and contact metamorphism of existing rock

Question 17

What is uplift?

Answer 17

A type of disturbance that raises up a large area of earth’s crust which is caused by plate movement (convergent; continent vs continent). It raises rock units above sea level and exposes rock unit to erosional agents

Question 18

What is subsidence?

Answer 18

A type of disturbance that lowers a large area of earth’s crust which is caused by plate movement. It lowers rock units below sea level and exposes rock units to deposition of new sedimentary layers

Question 19

What is unconformity?

Answer 19

A gap in the rock record where layers have been eroded and new layers have been deposited on top.
The steps are deposition, uplift, erosion and subsidence, and deposition