©BRAINBARTER EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
ERTH2404 Final Exam Lec(6-12) Questions
With Correct Answers.
What is a strike? - answer✔Intersection of planar structure with a horizontal plane
What is a dip? - answer✔Inclination of planar structure in respect to horizontal level, measured
at 90° from the strike line
What are the geological structures produced by deformation? - answer✔Faults
Joints
Folds
What is deformation? - answer✔Alteration of size and/or shape of materials
What are normal stresses? - answer✔Tension and compression
What is strain? - answer✔Change in the shape and/or size of a body as a result of stress
What is elastic deformation? - answer✔When an object will return to its original shape when
the load is removed.
Strong rocks have a _________ modulus of Elasticity - answer✔High
Weak rocks have a _________ modulus of Elasticity - answer✔Low
1|Page
, ©BRAINBARTER EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
Igneous rock's strength is ________ - answer✔Strong
Sedimentary rock's and metamorphic rock's strength are_________ - answer✔Variable
At shallow depth(low pressure), rocks behave? - answer✔Elastically to elastic limit before
brittle failure
At middle to lower crust(higher confining pressure), rocks behave? - answer✔Elastically,
materials soften with increasing temperature(depth)
Brittle rocks fail abruptly producing what? - answer✔Fractures
Ductile rocks undergo plastic deformation producing what? - answer✔Undulations called folds
Factors controlling the brittleness of a rock are? - answer✔Rock composition and texture
Temperature and pressure
Presence of fluids
What are faults? - answer✔Major fractures, showing movement between rock blocks
What are joints? - answer✔Minor fractures, showing little or no movement between rock
blocks
What is a hanging wall fault? - answer✔Rock block above the fault; older
What is a footwall fault? - answer✔Rock block below the fault; younger
What is a dip slip fault? - answer✔Movement in the direction of dip, normal, and reverse.
2|Page
, ©BRAINBARTER EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
What movement type is a normal fault? - answer✔Gravity does the work; extension
What movement type is a reverse fault? - answer✔Compression
What movement type is a strike-slip fault? - answer✔Lateral, along strike
What is a thrust fault? - answer✔Low angle reverse fault; moves hanging wall rocks over
footwall rocks
What causes joints? - answer✔Internal stresses
What causes expansive joints? - answer✔Removal of overlying rocks by erosin
What causes cooling joints? - answer✔Thermal contraction/expansion in relation to igneous
processes
What are systematic joints? - answer✔Parallel, regularly spaced fractures
What causes systematic joints? - answer✔Regional uniform stress
What are non-systematic joints? - answer✔Randomly orientated fractures with irregular
orcurved joint faces
What causes non-systematic joints? - answer✔Local non-uniform stresses
What is a fold? - answer✔Geological structure formed when rocks are bent or curved as a result
of plastic deformation
3|Page
ALL RIGHTS RESERVED.
ERTH2404 Final Exam Lec(6-12) Questions
With Correct Answers.
What is a strike? - answer✔Intersection of planar structure with a horizontal plane
What is a dip? - answer✔Inclination of planar structure in respect to horizontal level, measured
at 90° from the strike line
What are the geological structures produced by deformation? - answer✔Faults
Joints
Folds
What is deformation? - answer✔Alteration of size and/or shape of materials
What are normal stresses? - answer✔Tension and compression
What is strain? - answer✔Change in the shape and/or size of a body as a result of stress
What is elastic deformation? - answer✔When an object will return to its original shape when
the load is removed.
Strong rocks have a _________ modulus of Elasticity - answer✔High
Weak rocks have a _________ modulus of Elasticity - answer✔Low
1|Page
, ©BRAINBARTER EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
Igneous rock's strength is ________ - answer✔Strong
Sedimentary rock's and metamorphic rock's strength are_________ - answer✔Variable
At shallow depth(low pressure), rocks behave? - answer✔Elastically to elastic limit before
brittle failure
At middle to lower crust(higher confining pressure), rocks behave? - answer✔Elastically,
materials soften with increasing temperature(depth)
Brittle rocks fail abruptly producing what? - answer✔Fractures
Ductile rocks undergo plastic deformation producing what? - answer✔Undulations called folds
Factors controlling the brittleness of a rock are? - answer✔Rock composition and texture
Temperature and pressure
Presence of fluids
What are faults? - answer✔Major fractures, showing movement between rock blocks
What are joints? - answer✔Minor fractures, showing little or no movement between rock
blocks
What is a hanging wall fault? - answer✔Rock block above the fault; older
What is a footwall fault? - answer✔Rock block below the fault; younger
What is a dip slip fault? - answer✔Movement in the direction of dip, normal, and reverse.
2|Page
, ©BRAINBARTER EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
What movement type is a normal fault? - answer✔Gravity does the work; extension
What movement type is a reverse fault? - answer✔Compression
What movement type is a strike-slip fault? - answer✔Lateral, along strike
What is a thrust fault? - answer✔Low angle reverse fault; moves hanging wall rocks over
footwall rocks
What causes joints? - answer✔Internal stresses
What causes expansive joints? - answer✔Removal of overlying rocks by erosin
What causes cooling joints? - answer✔Thermal contraction/expansion in relation to igneous
processes
What are systematic joints? - answer✔Parallel, regularly spaced fractures
What causes systematic joints? - answer✔Regional uniform stress
What are non-systematic joints? - answer✔Randomly orientated fractures with irregular
orcurved joint faces
What causes non-systematic joints? - answer✔Local non-uniform stresses
What is a fold? - answer✔Geological structure formed when rocks are bent or curved as a result
of plastic deformation
3|Page
