Relative Dating

Question 1

How do index fossils help scientists?

Revolt · Accepted Answer

They aid in comparison of rock layers at distant locations.

Question 2

Which is the first step that geologists must do to compare rock layers at distant locations?

Revolt · Accepted Answer

identify index fossils in one or more layers at one location

Question 3

Which phrase describes the absolute age of a rock?

Revolt · Accepted Answer

is the number of years since it formed

Question 4

Which characteristic is shared by intrusions and faults?

Revolt · Accepted Answer

All are younger than surrounding rocks.

Question 5

In which situation is the principle of cross-cutting relationships useful in determining relative age?

Revolt · Accepted Answer

A fault breaks through sedimentary layers.

Question 6

Which correctly lists three different geologic features that help scientists determine the relative ages of rocks by their positions?

Revolt · Accepted Answer

index fossils, intrusions, and cross-cutting relationships

Question 7

The image shows sedimentary rock layers with index fossils and a fault.

Revolt · Accepted Answer

Layer 2 and layer 9 are the same relative age.

Question 8

A geologist finds some tilted sedimentary rock layers.Which conclusion can the geologist draw by looking at the rock layers?

Revolt · Accepted Answer

They were originally deposited horizontally.

Question 9

Which statement explains one reason why unconformities occur?

Revolt · Accepted Answer

No sediment is deposited over a long time.

Question 10

The diagram shows horizontal rock layers.

Revolt · Accepted Answer

Layer C is younger than layer A.

Relative Dating Answers