GEOLOGY 1500 MIDTERM EXAM QUESTIONS WITH VERIFIED SOLUTIONS LATEST UPDATE 2026
Orogeny - Answers mount building event that forms elongate ranges called mountain belts or
orogens
Brittle deformation - Answers breaks cracks
Plastic Deformation - Answers flattens / elongates without breaking
Stress - Answers amount of force applied per unit area of a rock
joints - Answers natural cracks in a rock
fracture - Answers fracture on which sliding occurs and earthquakes can be generated
Reverse Dip-slip fault - Answers hanging wall up with steep dip
Thrust Dip-slip fault - Answers hanging wall up with gentle dip
Normal Dip-slip - Answers hanging wall down
Strike-slip - Answers a type of fault where rocks on either side move past each other sideways
oblique-slip fault - Answers a fault in which sliding occurs diagonally along the fault plane
Stress: compression, tension, sheer
Strain: change in shape of rock caused by stress - Answers What are the causes of mountain
building?
Isostatic adjustment - Answers buoyancy force pushing lithosphere up equals gravitational force
pulling lithosphere down
Orogenic collapse - Answers mountains began to collapse under their own weight and spread
laterally
Volcano - Answers an erupting vent where molten rock reaches the Earth's surface or the
hill/mountain built from products of eruptions
Vesicles - Answers holes formed in igneous rocks from preservation of gas bubbles in magma as
it cools quickly
Active volcano - Answers a volcano that is erupting or has shown signs that it may erupt in the
near future
dormant volcano - Answers A volcano that has not erupted for a long time, but may erupt again
one day.
, Extinct volcano - Answers a volcano that no longer erupts
o Basaltic lava flows: low viscosity that travels long distance
o Andesitic lava flows: too viscous to flow far
o Felsic: very viscous that could pile in a dome-shaped mass - Answers What are the three types
of lava composition and its effect on flow?
lava flows
gasses and aerosols
deposits - Answers What are the three products of volcanic eruption?
Tephra/pyroclastic devris
Basaltic eruptions: Lava fountain, lapilli, bombs and blocks
Andesitc and Rhyolitic eruptions: ash, pumice lapilli,§ accretionary lapilli, pyrocatisc flow, tuff
- Debris flow: snow, ice, rain mixed with debris
- Lahars: ash-rich debris + water = lahar that travels for tens of km - Answers What are the
volcanic deposits?
- Shield: shallow with broad gentle dome, produces wide flat flows, effusive style
- Cinder cones: subaerial consisting of cone-shaped pile of tephra where slopes are close to the
maximum slope that loose fragments can sustain before sliding down, explosive style
- Stratovolcano: large, cone-shaped with alternating layers of lava and tephra, explosive and
effusive - Answers What are the three volcano types and their eruption styles
Pyroclastic flow, falling as, high elevation aircrafts - Answers What are the three volcanic hazards
other than lava?
Epicenter - Answers location at the surface directly above the focus of an earthquake, typically
associated with strong damage
Focus - Answers The location where a fault slips during an earthquake
Fault - Answers a planar fracture or discontinuity in a volume of rock across which there has
been significant displacement as a result of rock-mass movements
Seismograph - Answers instrument used to measure seismic energy
Tsunami - Answers sudden displacement of water from disturbance of seafloor
Orogeny - Answers mount building event that forms elongate ranges called mountain belts or
orogens
Brittle deformation - Answers breaks cracks
Plastic Deformation - Answers flattens / elongates without breaking
Stress - Answers amount of force applied per unit area of a rock
joints - Answers natural cracks in a rock
fracture - Answers fracture on which sliding occurs and earthquakes can be generated
Reverse Dip-slip fault - Answers hanging wall up with steep dip
Thrust Dip-slip fault - Answers hanging wall up with gentle dip
Normal Dip-slip - Answers hanging wall down
Strike-slip - Answers a type of fault where rocks on either side move past each other sideways
oblique-slip fault - Answers a fault in which sliding occurs diagonally along the fault plane
Stress: compression, tension, sheer
Strain: change in shape of rock caused by stress - Answers What are the causes of mountain
building?
Isostatic adjustment - Answers buoyancy force pushing lithosphere up equals gravitational force
pulling lithosphere down
Orogenic collapse - Answers mountains began to collapse under their own weight and spread
laterally
Volcano - Answers an erupting vent where molten rock reaches the Earth's surface or the
hill/mountain built from products of eruptions
Vesicles - Answers holes formed in igneous rocks from preservation of gas bubbles in magma as
it cools quickly
Active volcano - Answers a volcano that is erupting or has shown signs that it may erupt in the
near future
dormant volcano - Answers A volcano that has not erupted for a long time, but may erupt again
one day.
, Extinct volcano - Answers a volcano that no longer erupts
o Basaltic lava flows: low viscosity that travels long distance
o Andesitic lava flows: too viscous to flow far
o Felsic: very viscous that could pile in a dome-shaped mass - Answers What are the three types
of lava composition and its effect on flow?
lava flows
gasses and aerosols
deposits - Answers What are the three products of volcanic eruption?
Tephra/pyroclastic devris
Basaltic eruptions: Lava fountain, lapilli, bombs and blocks
Andesitc and Rhyolitic eruptions: ash, pumice lapilli,§ accretionary lapilli, pyrocatisc flow, tuff
- Debris flow: snow, ice, rain mixed with debris
- Lahars: ash-rich debris + water = lahar that travels for tens of km - Answers What are the
volcanic deposits?
- Shield: shallow with broad gentle dome, produces wide flat flows, effusive style
- Cinder cones: subaerial consisting of cone-shaped pile of tephra where slopes are close to the
maximum slope that loose fragments can sustain before sliding down, explosive style
- Stratovolcano: large, cone-shaped with alternating layers of lava and tephra, explosive and
effusive - Answers What are the three volcano types and their eruption styles
Pyroclastic flow, falling as, high elevation aircrafts - Answers What are the three volcanic hazards
other than lava?
Epicenter - Answers location at the surface directly above the focus of an earthquake, typically
associated with strong damage
Focus - Answers The location where a fault slips during an earthquake
Fault - Answers a planar fracture or discontinuity in a volume of rock across which there has
been significant displacement as a result of rock-mass movements
Seismograph - Answers instrument used to measure seismic energy
Tsunami - Answers sudden displacement of water from disturbance of seafloor
