MAKEUP EXAM Flashcards
Which foliated metamorphic rock is characterized by large grain size (you would not even need a 10x power handlens to see the minerals) with either muscovite mica flakes or biotite mica flakes being very visible because they reflect light?
schist
if mud in very shallow marine waters dries out at a low tide in a very very warm environment, what structure is likely to be preserved?
mud cracks
Regional Metamorphism is associated with what geologic setting?
convergent plates
the accumulation of clay minerals in a soil profile creates a “pan” or “fragipan” in the soil. why does the presence of a pan create problems for a rural home owner who has a septic tank?
the pan is poorly drained and it does not provide for a proper leaching bed
the soils developed on till in central ohio are about 20,000 years old. the glacier had picked up great amounts of carbonate rocks to form till, but now, in places at the crest of till mounds, there is no carbonate material in the upper 30 inches of soil. what happened to the carbonates in the soil?
it was leached from the soil
An outpouring of lava in the columbia river valley millions of years ago baked the soil beneath the lava. the soil had formed on an earlier lava flow. what type of metamorphism caused the alteration of the soil?
contact
where would you expect to find the youngest basalt in the floor of the atlantic ocean?
in the mid atlantic rift zone
clay minerals are formed as the result of chemical weathering of what minerals?
feldspars
of the soil forming factors, which of the following is directly related to the climate?
organics
which of the following is a metamorphic rock which shows definite banding: light colored silicate minerals and dark colored Fe-Mg silicate minerals in alternate bands
gneiss
where in the oceans of the world would you expect to find the deepest water?
trenches at subduction zones
what is the current method used by the USGS when reporting the intensity of earthquakes?
Moment Magnitude
what is the composition if the core of the earth as determined remotely by physical properties of earth?
mostly iron with some Nickel and other elements
the pacific plate is now moving NW over the Hawaiian hot spot. a few million years ago, the plate moved north over this hot spot. what is happening to the ocean floor beneath guyots at the far northern end of this chain?
it has been subducted
what is the appropriate name for the clastic sedimentary rock which contains silt and clay and is thinly bedded?
shale
which of the following rocks is an evaporite?
gypsum
which of the following metamorphic rocks is a non-foliated rock formed from limestone?
marble
what are the two major agents of metamorphism?
temperature and pressure
which portion of the interior of earth reflects the greatest volume of rock in the model of earth?
the mantle
which clay mineral structure has high shrink-swell potential?
some 2:1 structure clay minerals
which earthquake wave arrives second as recorded by a seismograph?
S body wave
what causes earthquakes?
brittle rock breaks
as rain falls, it combines with certain gases in the atmosphere (the gas dissolves in the rain) to create acid rain which can dissolve carbonate rocks. which gas in the atmosphere dissolves in the raindrops?
carbon dioxide
what is the pH in a swamp?
acidic
what does the USGS suggest you do if you are in a building on the seventh floor during an earthquake?
drop - cover - and hold
which part of a soil profile identifies the parent material of the soil?
the C horizon
what initiates the formation of a sea floor?
a continent: continent divergent boundary
what type of structures are exposed in the appalachian mountains on chestnut ridge a few miles east of morgantown wv?
fold mountains