CPG CPG Structural Geology & Tectonics 2

Question 1

The San Andreas Fault in California is best classified as what type of fault?

Accepted Answer

Right-lateral strike-slip fault

Answer

The San Andreas is a right-lateral strike-slip fault; an observer on either side sees the opposite block move to the right.

Question 2

A horst is best defined as:

Accepted Answer

An uplifted block bounded by two normal faults

Answer

A horst is an elevated crustal block bounded on both sides by normal faults, forming a ridge or plateau.

Question 3

The Rio Grande Rift in New Mexico is an example of which tectonic feature?

Accepted Answer

A continental extensional rift

Answer

The Rio Grande Rift is an active continental rift zone where the crust is being pulled apart, forming a series of north-trending grabens.

Question 4

Foliation in metamorphic rocks is primarily created by:

Accepted Answer

Directed (non-hydrostatic) stress during metamorphism

Answer

Foliation develops when directed stress causes platy or elongate minerals to recrystallize perpendicular to the maximum compressive stress.

Question 5

Which structural feature places older rocks stratigraphically above younger rocks?

Accepted Answer

A thrust fault

Answer

Thrust faults transport older rocks over younger rocks, inverting the normal stratigraphic order across the fault plane.

CPG - Certified Professional Geologist Practice Test