Structural Geology and Tectonics Flashcards
7 cards from real ASBOG practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Structural Geology and Tectonics flashcards as text
Which type of fold has its oldest rocks in the core?
Answer: Anticline
Anticlines arch upward with the oldest rocks exposed at their core due to erosion.
A thrust fault is characterized by which dip angle range?
Answer: Less than 45°
Thrust faults dip at less than 45° and involve the hanging wall moving up relative to the footwall under compressional stress.
The Wilson Cycle describes the repeated opening and closing of which geological feature?
Answer: Ocean basins
The Wilson Cycle describes the cyclical opening and closing of ocean basins driven by plate tectonics.
What is the term for the angle between a fault plane and the horizontal?
Answer: Dip
Dip is the angle measured downward from horizontal to the fault or bedding plane.
Boudinage structures form when a competent layer is subjected to what type of stress?
Answer: Extension parallel to layering
Boudinage forms when a rigid layer is stretched and necked into sausage-shaped segments under extensional stress parallel to layering.
Which plate boundary type is associated with transform faults?
Answer: Conservative boundary
Transform (conservative) boundaries involve plates sliding horizontally past each other along transform faults with no creation or destruction of crust.
A conjugate fault set consists of two fault orientations that indicate what about the principal stress axes?
Answer: The maximum stress bisects the acute angle between faults
In a conjugate fault set, the maximum compressive stress (σ1) bisects the acute angle between the two fault planes.