Review Concepts on Deformation and Metamorphism

Which statement regarding synclines is true? A. Limbs dip toward the axial plane where the oldest strata are exposed. B. Limbs dip toward the axial plane where the youngest strata are exposed. C. Limbs dip away from the axial plane where the oldest strata are exposed. D. Limbs dip away from the axial plane where the youngest strata are exposed. Rock folding

Which statement regarding synclines is true? A. Limbs dip toward the axial plane where the oldest strata are exposed. B. Limbs dip toward the axial plane where the youngest strata are exposed. C. Limbs dip away from the axial plane where the oldest strata are exposed. D. Limbs dip away from the axial plane where the youngest strata are exposed. Rock folding

What characterizes a fold as being a plunging fold? A. The limbs dip at different angles from one another. B. The limbs both dip in the same direction. C. The axial plane is not vertical. D. The fold axis is not horizontal. Rock folding

What characterizes a fold as being a plunging fold? A. The limbs dip at different angles from one another. B. The limbs both dip in the same direction. C. The axial plane is not vertical. D. The fold axis is not horizontal. Rock folding

Faults Faults are classified by: A.Map pattern B.Stress field C.Age D.Dip and relative motion

Faults Faults are classified by: A.Map pattern B.Stress field C.Age D.Dip and relative motion

Faults A normal Fault is characterized by A.Tensional Stress B.Steep Dip (>45 o ) C.Hanging wall down relative to footwall D.All of the above

Faults A normal Fault is characterized by A.Tensional Stress B.Steep Dip (>45 o ) C.Hanging wall down relative to footwall D.All of the above

Depth, km Asthenosphere Continental crust Regional metamorphism Oceanic crust Oceanic lithosphere Shock metamorphism Regional metamorphism Regional high-pressure metamorphism Contact metamorphism Burial metamorphism Continental mantle lithosphere Water Seafloor metamorphism

Which kind of metamorphism is caused primarily by increasing temperature with little change in pressure? A. Regional Metamorphism B. Contact metamorphism C. Burial Metamorphism D. Subduction-zone metamorphism The lithosphere and asthenosphere interact to metamorphose rock

Which kind of metamorphism is caused primarily by increasing temperature with little change in pressure? A. Regional Metamorphism B. Contact metamorphism C. Burial Metamorphism D. Subduction-zone metamorphism The lithosphere and asthenosphere interact to metamorphose rock

High-pressure regional metamorphism is most closely associated with which tectonic environment? A. Continental rifting B. Mid-ocean ridge C. Subduction zone D. Meteorite impact The lithosphere and asthenosphere interact to metamorphose rock

High-pressure regional metamorphism is most closely associated with which tectonic environment? A. Continental rifting B. Mid-ocean ridge C. Subduction zone D. Meteorite impact The lithosphere and asthenosphere interact to metamorphose rock

Seafloor metamorphism that occurs at mid-ocean ridges is caused by: A. Directed pressure B. Confining pressure C. Metasomatism D. All of the above The lithosphere and asthenosphere interact to metamorphose rock

Seafloor metamorphism that occurs at mid-ocean ridges is caused by: A. Directed pressure B. Confining pressure C. Metasomatism D. All of the above The lithosphere and asthenosphere interact to metamorphose rock

Increasing intensity of metamorphism Increasing crystal size Increasing coarseness of foliation Low gradeIntermediate grade High grade

SlatePhyllite Schist (abundant micaceous minerals) Gneiss (fewer micaceous minerals) Migmatite Slaty cleavageSchistosityBanding DiagenesisLow grade Intermediate grade High grade

Canada NY VT ME NH MA CT RI Isograds Key: Not metamorphosed Chlorite zone Biotite zone Garnet zone Staurolite zone Sillimanite zone Low grade Medium grade High grade Index minerals define metamorphic zones. Isograds can be used to plot the degree of metamorphism.

Degree of metamorphism Diagenesis Greenschists LowIntermediate Amphibolites Granulites High Chlorite White mica (mainly muscovite) Biotite Garnet Staurolite Sillimanite Kyanite Albite (sodium plagioclase) With increasing metamorphic grade, mineral composition changes. Mineral suites define metamorphic facies.

How do crystal size and foliation change with increasing intensity of metamorphism? A. Grain size increases and foliation becomes less coarse. B. Grain size decreases and foliation becomes coarser. C. Both grain size and foliation coarseness decrease. D. Both grain size and foliation coarseness increase. Texture, index minerals, grade, and facies describe metamorphism

How do crystal size and foliation change with increasing intensity of metamorphism? A. Grain size increases and foliation becomes less coarse. B. Grain size decreases and foliation becomes coarser. C. Both grain size and foliation coarseness decrease. D. Both grain size and foliation coarseness increase. Texture, index minerals, grade, and facies describe metamorphism

Which list places foliation textures in order of increasing metamorphic grade (low grade to high grade)? A. Slate, gneiss, phyllite, schist B. Slate, phyllite, schist, gneiss C. Gneiss, schist, slate, phyllite D. Gneiss, phyllite, schist, slate Texture, index minerals, grade, and facies describe metamorphism

Which list places foliation textures in order of increasing metamorphic grade (low grade to high grade)? A. Slate, gneiss, phyllite, schist B. Slate, phyllite, schist, gneiss C. Gneiss, schist, slate, phyllite D. Gneiss, phyllite, schist, slate Texture, index minerals, grade, and facies describe metamorphism

Metamorphic facies are defined by: A. Suites of minerals B. Foliation textures C. Pressures and temperatures D. Tectonic environments Texture, index minerals, grade, and facies describe metamorphism

Metamorphic facies are defined by: A. Suites of minerals B. Foliation textures C. Pressures and temperatures D. Tectonic environments Texture, index minerals, grade, and facies describe metamorphism