GEOL MAKEUP 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
what lock and dam on the great lakes allows ships to bypass niagara falls?
welland
which rock is an excellent aquaclude in west virginia?
shale
the rotation of a mass of colluvium in west virginia after heavy spring rainfall would best be termed what type of mass movement feature?
slump
for decades in the great valley of california, ground water has been pumped to provide irrigation for the many crops. after so many years of pumping, what has happened to the land in many places?
the surface has subsided
when a river floods, the water/ sediment mixture leaves the river channel and spreads out on the adjacent floodplain. to prevent damage during floods, sand bags can be placed to channel the water. what natural accumulation of sediment can be created by the ricer itself during flooding as the water/ sediment leave the channel?
a levee
what term is applied to the load transported by a river which stays in contact with the river bottom. it can be deposited and the move again when the discharge of the river is sufficient enough to move the particles.
bed load
anticlines and synclines in the appalachian mountains were created by what type of force applied?
compression
what is the best definition of the 100 year flood?
there is a 1% chance that a flood of this magnitude will occur in any one year
the sierra nevada mountains in california were formed by what type of mountain building activity?
a massive normal fault
what invasive species was introduced to the great lakes by ships from the baltic entering the great lake system?
quagga and zebra mussels
what type of forces can result in a normal fault if the rocks are brittle and break?
tension
what water is pumped from a well, how does the water table around the well respond?
there is a drawdown of the water table
during construction of a single family home on a slope just outside of Morgantown, a six-foot high wall of colluvium was exposed. The exposure will be left until next spring when weather conditions are better and then the house will be built. predict what might happen over the winter?
the wall of colluvium might collapse
which of the following aquifers in West Virginia result from joints formed in rocks which otherwise are not permeable. in other words, water flows in the joints formed when the appalachian mountains were formed. The aquifer is in:
Coal
which two of the great lakes share the same water plain? in other word, flat water joins the two and there is no need for locks and dams of continual dredging to allow ships to pass between the two lakes
Huron and Erie
the mass movement of weathered volcanic rock and ash on a volcano is specifically termed a lahar. what general term of mass movement features represents a lahar?
mudflow
when you visited the sites for bonus quiz #5 one of the methods to retain a slope was the construction of gabions. these are wire baskets filled with rocks. at which location did you sketch or take a picture of gabions?
behind the apartments on college avenue
in urban areas, what change is there with respect to flooding events?
floods occur more often and are more severe
how much time do you have to prepare for flash floods?
an hour or two at best
in tampa florida the rocks underlying the area are limestones. many caves have formed and if groundwater is pumped out of the caves, the support of the cave roof is removed. what can happen?
a sinkhole could form
what is happening to the cryosphere at the present time?
it is diminishing rapidly
I spoke of earths history as first being “astronomic earth” and then evolving into “geologic earth”. what is the absolute date that is assigned to the beginning of geologic earth?
4.6 billion years ago
what is the tectonic plate boundary condition which has resulted in the formation of the cascade range? [O= oceanic plate; C= continental plate]
O:C convergent
what is the mineral family in which quartz [SiO2] is classified?
silicates
what is the rock name of the fine-grained, black, extrusive igneous rock formed by lava on the island of Hawaii?
basalt
Identify the most recent volcanic eruption in the U.S. form the following list
Mt. St. Helens
what mineral will “fizz” if a drop of dilute hydrochloric acid [HCl] is placed on the mineral?
calcite
what type of bond is present as 100% of the bonding in the mineral halite [NaCl]
ionic
the element iron can exist in minerals as two ionic states: what are the two possible charges on an ion of iron in minerals?
+2
which isotope of Hydrogen [H] has the mass of two atomic mass units because there is one proton and one neutron in the nucleus?
H2
what is the name of the intrusive igneous rock which contains quartz, K-spar, some Na-rich plagioclase feldspar, and a small percent of Fe-Mg silicate minerals?
granite
the volcanoes which form all the the Aleutian Islands were created at what type of plate boundary?
O:O convergent
what is normally the most abundant gas emitted during a volcanic eruption?
water vapor
what are the two most life threatening features of a volcanic eruption?
lahars & pyroclastic flows
what is the geologic term for the San Andreas fault in California?
a right-handed strike slip transform fault
in general, what is the model of the interior of Earth [below the crust]?
it is divided into a mantle and a core
what gas can be emitted before a volcanic eruption which will settle in depressions and suffocate plants and small animals because it is heavier than air?
carbon dioxide
what does a swarm of shallow earthquakes beneath a volcano suggest?
a possible eruption
what mineral is dominant in the ultramafic igneous rocks which form earth’s mantle?
olivine
what feldspar is the most abundant in gabbro?
Ca-rich plagioclase
I drew a vertical line A-A’ on the diagram. This line reflects felsic igneous rock composition. what is the percent composition of Potassium feldspar in the rock which would form along A-A’?
a bit over 20%
the mass of an isotope is determined by the sum of the masses of:
protons and neutrons in the nucleus
fig. 1.4 is a simple cartoon for the main building block of all silicate minerals, the silicon-oxygen tetrahedral. what is the ratio of Si: O in the construction of the Si-O tetrahedral?
1 Si and 4 O [1:4]
