Geology 100 exam 2 ch 5-7

The movement of material by moving wind, water, or ice is a process called (1)________ whereas the process that breaks down solid rock into loose sediment is called (2)________. A. (1) mechanical weathering (2) chemical weathering B. (1) chemical weathering (2) mechanical weathering C. (1) erosion (2) weathering D. (1) weathering (2) erosion E. (1) deposition (2) weathering F. (1) weathering (2) deposition

C. 1. Erosion 2. weathering

Forms of mechanical weathering A. oxidation B. frost wedging C. salt expansion D. exfoliation E. root wedging F. Dissolution

B. frost wedging, C. salt expansion, E. root wedging

Which of the following statements about metamorphism is FALSE? A. metamorphic rocks form from existing sedimentary, igneous, or metamorphic rocks B. metamorphism involves melting of existing rocks to form new minerals C. during metamorphism, existing minerals are transformed into new minerals D. metamorphism is controlled by pressure, temperature, fluids, and time E. metamorphic means "change of form" F. A protoliths metamorphoses into a metamorphic rock.

B. metamorphism involves melting of existing rocks to form new minerals

What is the most common material found in sandstones? A. Feldspar B. Quartz C. Lithic fragments D. Chemical sediments E. Pebble F. Granule

B. quartz

What mainly causes agents of transport, like wind or water, to deposit sediment? A. Increases speed B. Decreased speed C. Increased temperature D. Decreased temperature E. Increased weathering F. Decreased weathering

B. decreased speed

The remains of sea organisms with shells made of silica accumulate on ocean bottoms as biogenic sediment that eventually forms a type of rock called: A. rock salt B. limestone C. chert D. fossiliferous limestone E. peat F. chalk

C. Chert

. Which of the following depositional environments has the least water? A. Fluvial B. Lacustrine C. Eolian D. Abyssal E. Paludal F. Littoral

C. Eolian

Which of the following is the largest geologic time unit? A. Period B. Era C. Eon D. Epoch E. Age

C. Eon

Which of these would likely produce the most reliable absolute age of formation from radiometric dating techniques? A. High-grade metamorphic rock B. Low-grade metamorphic rock C. Igneous rock D. Clastic sedimentary rock E. Chemical sedimentary rock F. Sediments

C. Igneous rock

Which of these can indicate a paleocurrent direction? SELECT ALL THAT APPLY A. Ripple marks B. Mudcracks C. Imbrication D. Cross bedding E. Raindrop impressions F. Bioturbation

C. Imbrication, D. Cross bedding

Heat promotes recrystallization by __________. A. separating ultramafic elements from mafic ones B. causing minerals to melt C. increasing atomic vibration D. stripping away electrons E. adding catalysts to reactions F. increasing pressure

C. Increasing atomic vibration

Which of these indicate changing water conditions, from wet to dry, in an arid land? A. Graded bedding B. Cross bedding C. Mudcracks D. Ripple marks E. Bioturbation

C. Mudcracks

What makes a shale different from a mudstone? A. Denser B. Darker colored C. Thinly bedded D. Different minerals E. Coarser grained F. Less dense

C. thinly bedded (lamination)

conglomerate has the same grain size as A. clay B. silt C. mud D. pebble E. sand F. none of the above

D. Pebble

What does a phase diagram show? A. Various minerals that are grouped in different metamorphisms B. Tectonic settings for different mineral phases C. Depositional environments for different mineral phases D. Pressure and temperature ranges at which different minerals form E. The progression of phases from low grade to high grade metamorphism F. Minerals that form in different terranes

D. Pressure and temperature ranges at which different minerals form

Sediment particles in quartz sandstone that formed in an eolian environment are typically: A. poorly sorted and angular B. poorly sorted and well rounded C. well sorted and angular D. well sorted and well rounded E. made of feldspar F. made of lithic fragments

D. Well sorted and well rounded

In stratigraphy, the principle of stratigraphic superposition states that: A. all sedimentary beds start off being horizontal B. all sedimentary beds are separated by bedding planes C. a sedimentary bed is younger than the bed above it and older than the bed below it D. a sedimentary bed is older than the bed above it and younger than the bed below it E. a sedimentary bed must be older than any feature that cuts through it or disrupts it F. a sedimentary bed is younger than any adjacent igneous rock

D. a sedimentary bed is older than the bed above it and younger than the bed below it

Minerals like halite and calcite are particularly prone to chemical weathering through the process of dissolution. As a result, the following type of rock is prone to this type of weathering: A. limestone B. rock salt C. marble D. all of the above E. none of the above

D. all of the above

When rock undergoes very high directed stress because of tectonism, the rock will be "squished" in one direction. This metamorphic process is called _____. A. contact metamorphism B. regional metamorphism C. shock metamorphism D. burial metamorphism E. fault metamorphism F. impact metamorphism

D. burial metamorphism

Into what category of sedimentary rocks does the type of rock fall that forms by the evaporation of water and consequent precipitation of minerals like halite? A. organic B. detrital C. clastic D. chemical E. biochemical F. none of the above

D. chemical

What is the most likely cause of a sediment with highly rounded grains? A. Stronger bedrock B. Shorter time since weathering C. Lack of water in environment D. Longer distance transported E. Higher temperatures in environment F. Glacial transport

D. longer distance transported

What are the components of soil A. Weathered rock B. Unweathered rock C. Eroded rock D. Organic material (humus) E. Water F. Air G. Regolith

D. organic material, F. air, and E. water G. regalith

Which of the following statements regarding lithostatic pressure is correct? A. it is caused by the weight of the overlying rocks B. it is equal in magnitude from all directions C. it causes rocks to decrease in volume but it does not change the rock shape D. it causes minerals to recrystallize E. all of the above F. none of the above

E. All of the above

Which of the following depositional environments are characterized by fine-grained sediment (mud)? SELECT ALL THAT APPLY A. Lacustrine B. Alluvial C. Abyssal D. Eolian E. Fluvial F. Glacial

E. Fluvial, A. Lacustrine

Which of these fits polymorphism? A. Same mineral, different crystal structures B. Same mineral, different chemical formulas C. Same crystal structure, different chemical formulas D. Same crystal structure, different minerals E. Same composition, different crystal structures F. Same composition, different chemical formulas

E. Same composition, different crystal structures

Which of the following statements about sedimentary rocks is TRUE? A. sedimentary rocks only make up about 5% of the crust B. sedimentary rocks are the type of rock we see most often at the Earth's surface C. sedimentary rocks indicate the past environment D. the process of turning loose sediment into rock is called lithification E. all of the above F. none of the above

E. all of the above

When initially flat-lying beds get tilted and eroded, then new flat-lying beds get deposited on top, the type of unconformity that results is called a/an: A. paraconformity B. nonconformity C. nondepositional unconformity D. disconformity E. angular unconformity

E. angular unconformity

Which of the following pairs of words about sedimentary rocks belong together? A. detrital and evaporites B. chemical and pebbles C. biochemical and coal D. chemical and chalk E. detrital and sandstone F. clastic and chert

E. detrital and sandstone

The global climate changes in geologic past resulted from: A. Rivers changing course B. Glaciers advancing and retreating C. Lakes swelling and evaporating D. Deserts migrating and growing E. Sea level rising and falling F. Earth changing its movements

F. Earth changing its movements

A rock stratum is tiled noticeably from horizontal. What is the most reasonable conclusion you can draw? A. The stratum was deposited on the angle of the continental slope B. A tectonic event has occurred in the area since deposition of the stratum C. A meteorite struck that region, and the stratum is bowed up near the margin of the crater D. A volcano punched through the region deforming the stratum E. The layers have slowly rotated as the ground around them has been compressed with lithification F. Erosion removed the base strata, tilting the overlying strata.

F. Erosion removed the base strata, tilting the overlying strata.

The result of differential stress on rocks can: A. cause the rocks to partially erode. B. cause new minerals to grow randomly in the protolith. C. cause mineral crystals to align parallel to each other. D. cause mineral crystals to dissolve. E. cause mineral crystals to melt. F. cause mineral crystals to shrink.

F. cause mineral crystals to shrink

What are parts of the process of lithification A. Cementation B. Compaction C. Recrystallization D. Crystallization E. Melting F. Deposition

F. deposition, B. compaction, A. cementation

The correct combination of ripple shape and potential environment in which the ripple developed is: A. symmetric / single direction wind flow B. symmetric / river channels C. asymmetric / ocean waves D. asymmetric / beaches E. asymmetric / river channels F. none of the above is correct

F. none of the above is correct

The epoch that we currently live in is called the:

Holocene

The type of sedimentary structure that describes a layer of sediment in which the grain size steadily decreases from the bottom to the top of the layer is called:

Lamination

What materials were dated to determine the age of the Earth?

Meteorites

An example of a trace fossil: SELECT ALL THAT APPLY A. fossilized shells B. fossilized bones C. dinosaur footprint D. Fossil poop (coprolites) E. worm trails F. fossilized seeds

C. dinosaur footprint D. Fossil poop (coprolites) E. worm trails

A foliation develops in a metamorphic rock because: A. platy minerals always align with each other during any type of metamorphism B. the original rock that got metamorphosed must have had a foliation in it C. directed stress causes minerals to align parallel to each other D. high temperatures during metamorphism always cause minerals to recrystallize with a foliation E. a platy form is the optimal shape when mineral crystals recrystallize F. this is what defines a metamorphic rock in the first place

C. directed stress causes minerals to align parallel to each other

arkose has the same grain size as A. clay B. silt C. sand D. pebble E. boulder F. none of the above

C. sand

What is the number-one direct cause of changes in depositional environment?

The rise and fall of sea levels

The protolith of marble is ______.

limestone

The protolith of slate is ______.

shale

If the half-life of an isotope is 1 million years, and 100 of the isotopes are in an igneous rock when it first forms, how old will the rock be when there are only 25 of these isotopes left in the crystal? (If this question is on the exam, some numerical values will be modified, but they remain as simple so that you do not need a calculator.) A. 1 million years old B. 2 million years old C. 3 million years old D. 4 million years old E. 5 million years old F. 25 million years old

A. 1 million years old

Which of the following are index minerals? SELECT ALL THAT APPLY A. Chlorite B. Garnet C. Quartz D. Kyanite E. Staurolite F. Biotite

A. Chlorite, B. Garnit, D. Kyanite, E. Staurolite, F. Biotite

A bed with a mix of sandstone and conglomerate sedimentary rocks with ripple marks, cross beds, and leaf fossils likely formed in which depositional environment? A. Fluvial B. Alluvial C. Paludal D. Eolian E. Glacial F. Abyssal

A. Fluvial

Why are fossils so uncommon in older rocks? A. Life had not developed hard body parts yet B. Early organisms were so small that the fossils are hardly discovered C. Fossilized early organisms resemble mineral grains D. The older rocks that include fossils are too deep in the crust to collect and study E. Early organisms were not widespread enough to be found

A. Life had not developed hard body parts yet

About 540 million years ago, _____. SELECT ALL THAT APPLY A. The Proterozoic ended B. The Precambrian ended C. The Paleozoic began D. The Phanerozoic began E. The Paleogene began

A. The Proterozoic endedC. The Paleozoic began

A typical feature of the sediment particles in glacially produced tillite is that they: A. are poorly sorted and angular B. are poorly sorted and well rounded C. are well sorted and angular D. are well sorted and well rounded E. are fine grained F. thinly laminated

A. are poorly sorted and angular

Shale has the same grain size as A. clay B. silt C. sand D. pebble E. boulder F. none of the above

A. clay

When magma intrudes pre-existing country rock, the rock will be cooked by the magma. This metamorphic process is called _____. A. contact metamorphism B. regional metamorphism C. shock metamorphism D. burial metamorphism E. fault metamorphism F. impact metamorphism

A. contact metamorphism

What directly causes sink holes A. dissolution B. frost wedging C. salt expansion D. exfoliation E. hydrolysis F. oxidation

A. dissolution

Examples of chemical weathering A. Exfoliation B. Salt expansion C. Dissolution D. Frost wedging E. Hydrolysis F. Oxidation

A. exfoliation, C. dissolution, E. hydrolysis, F. oxidation

Which of the following metamorphic rocks does not belong in the same list as the others? A. quartzite B. schist C. phyllite D. gneiss E. slate

A. quartzite

Which sequence list shows metamorphic rocks in order from low-grade to high-grade? A. slate→phyllite→schist→gneiss B. slate→phyllite→gneiss→schist C. phyllite→slate→schist→gneiss D. schist→slate→gneiss→phyllite E. gneiss→schist→slate→phyllite F. gneiss→schist→phyllite→slate

A. slate→phyllite→schist→gneiss

If we see a sedimentary bed that has a fault cutting through it as well as a dike that cuts through both the bed and the fault, we can use the principle of cross-cutting relationships to infer: A. the bed formed first, then the fault, then the dike B. the bed formed first, then the dike, then the fault C. the fault formed first, then the bed, then the dike D. the fault formed first, then the dike, then the bed E. the dike formed first, then the bed, then the fault F. the dike formed first, then the fault, then the bed

A. the bed formed first, then the fault, then the dike

In sedimentary rock types, the term clastic means the same thing as A. chemical B. biochemical C. organic D. detrital E. lithic F. biogenic

B. Biochemical

Which of the following are biochemical sedimentary rocks? SELECT THREE A. Coal B. Fossiliferous limestone C. Chalk D. Peat E. Shale F. Coquina G. Conglomerate H. Sandstone

B. Fossiliferous limestone, C. Chalk, F. Coquina

Which of the following statements about radioactivity is FALSE? SELECT ALL THAT APPLY A. radioactive dating is a technique of relative dating B. all isotopes of an element have the same number of neutrons and different numbers of protons C. in radioactive decay, daughter isotopes turn into parent isotopes D. all isotopes of an element have the potential to undergo radioactive decay E. the amount of parent isotopes is always increasing F. all available atoms of an unstable isotope will fully decay after two half-lives

B. all isotopes of an element have the same number of neutrons and different numbers of protons C. in radioactive decay, daughter isotopes turn into parent isotopes E. the amount of parent isotopes is always increasing F. all available atoms of an unstable isotope will fully decay after two half-lives

Why is the mineral zircon good for absolute dating? SELECT ALL THAT APPLY A. It is durable B. It contains uranium C. It reacts easily D. It contains potassium E. It forms in all igneous rocks F. It is widespread.

B. It contains uranium A. It is durable

10. Index minerals are ______. A. Any minerals that grow in metamorphic rocks. B. Minerals that only form at certain temperatures/pressures. C. Minerals that help classify metamorphic rocks. D. Minerals that form at high pressure. E. Minerals that grow in magma F. Minerals found in foliated rocks.

B. Minerals that only form at certain temperatures/pressures.

Which of the following statements about radioactivity is FALSE?: SELECT ALL THAT APPLY A. the rate of decay of an isotope never changes B. the amount of daughter isotopes is always decreasing C. all isotopes of any element decay D. all isotopes have the same half-life value E. decay rates are affected by the physical and chemical environment F. one half of the available unstable isotopes always decays during one half-life

B. the amount of daughter isotopes is always decreasing E. decay rates are affected by the physical and chemical environment

If we see a sedimentary bed that has a dike cutting through it as well as a fault that cuts through both the bed and the dike, we can use the principle of cross-cutting relationships to infer: A. the bed formed first, then the fault, then the dike B. the bed formed first, then the dike, then the fault C. the fault formed first, then the bed, then the dike D. the fault formed first, then the dike, then the bed E. the dike formed first, then the bed, then the fault F. the dike formed first, then the fault, then the bed

B. the bed formed first, then the dike, then the fault

Which of the soil horizons make up humus

O horizon (topsoil)

Which of the soil horizons make up topsoil

O horizon and A horizon