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ESS 101 Final
Terry Swanson
139
Geology
Undergraduate 1
03/15/2009

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Cards

Term
Besides frost wedging which of the following are examples of mechanical weathering?
Definition
Biotubation, spalling of boulders from range fires (only answers a and b)
Term
H+ ions utilized in hydrolysis weathering reactions come from___.
Definition
Carbonic Acid
Term
Over time angular joints will____due to surface weathering.
Definition
Become rounded
Term
Frost wedging occurs in rock because:
Definition
water expands when it freezes to from ice
Term
Joints facilitate weathering because____.
Definition
Permit water and other chemical agents to penetrate below the surface & Provide more surface area for the weathering front to attack
Term
Why did the depth of rilling increase on the limestone boulders deposited on the three glacial moraines?
Definition
The lower moraine was older and subjected to longer weathering.
Term
limestone will tend to precipitate in sea water when___.
Definition
Carbon dioxide content increases & is agitated by wave action.
Term
Which of the following transport agents generally results in cross beds?
Definition
Rivers
Term
Joints facilitate weathering because____.
Definition
permit water and other chemical agents to penetrate below the surface & provide more surface area for the weathering front to attack
Term
which of the following depositional events generally results in graded beds?
Definition
turbidity currents
Term
What diagnostic property would you use to determine that the cementing agent within sandstone is Fe2O3?
Definition
its reddish color
Term
Chert generally precipitates in deep ocean water because______.
Definition
silica is less soluble in cold water
Term
Rivers erosion tends to be greatest______fold structure.
Definition
near the axis of
Term
Oolites form from_____.
Definition
precipitation of calcite around sand grains oscillated by waves.
Term
a sedimentary rock unit with graded beds that fine towards the top would indicate_______.
Definition
that the rock unit has not been deformed (remains right side up)
Term
if a fault offset a layer of volcanic ash that is 15,000 years old and the fault was buried by a landslide deposit that is radiocarbon dated at 12,000 years old one can infer that the faulting event_____.
Definition
occurred prior to 12,000 years ago & occured after 15,000 years ago (both b and c are correct)
Term
according to the principle of inclusions the closest age for the formation of a conglomerate rock______.
Definition
would be the youngest clast (pebble) age comprising the conglomerate
Term
How might you recognize in the field that a disconformity exists between two sequences of rock?
Definition
you would find non-metamorphosed sedimentary rock in direct contact with an igneous pluton
Term
the zig zag pattern of rock units that can be observed while flying over pennsylvania is due to__________.
Definition
erosion of plunging (tilted) anticlines and synclines
Term
which of the following transport agents generally results in oscillation (symmetric ripples)?
Definition
ocean waves
Term
according to the principle of cross-cutting relationships, if a fault is found cutting across sedimentary strata, the reasonable conclusion would be that:
Definition
the fault is younger than the strata
Term
a minimum of______seismic stations is necessary to determine the focus of an earthquake.
Definition
3
Term
if an earthquake occurs, the_______waves are the second waves to arrive at a seismic station.
Definition
S
Term
topset beds of a delta________.
Definition
are graded to the elevation of the lake or sea level.
Term
in order to relieve stress buildup that would cause a magnitude 7 earthquake, approximately how many magnitude 5 earthquakes would have to occur?
Definition
900
Term
high temperature is conductive to_________deformation in rock.
Definition
ductile
Term
which plate boundaries tend to have the deepest focused earthquakes?
Definition
convergent
Term
the effusive eruptions on Iceland_______.
Definition
are composed of basaltic composition lava.
Term
the___________is exposed in the center of an eroding anticline.
Definition
oldest rock
Term
a reverse fault_________.
Definition
may have repeating strata exposed in a vertical cross-section & may result in older rock units overlying younger units overlying younger units in a vertical cross-section (only answers a and b)
Term
______________is an example of elastic deformation.
Definition
filling and emptying a reservoir & isostatic unloading of the earths lithosphere following deglaciation (b & c are correct)
Term
which metamorphic rock has been subject to the highest grade of heat and pressure?
Definition
gneiss
Term
why is quartz the most common mineral found in beach sand around Puget Sound?
Definition
quartz is lighter than all the other materials and can be washed futehr by waves.
Term
how did geologists determine the exact day of offset on the cascadia subduction one in 1700 AD?
Definition
they had accurate tsunami logs from japan that recorded the event
Term
as the northern great lakes isostratically rebound________?
Definition
their waters will eventually drain south through the Mississippi River system.
Term
Clastic sedimentary rocks are subdivided_______.
Definition
based on grain size of the constituent clasts
Term
who was one of the only survivors of the St. Pierre Nuee Ardente?
Definition
Raoul Sarteret
Term
The 1980 eruption of Mt. St. Helens was______previous large eruptions in the holocene.
Definition
less than
Term
Lahars generated from Mt. Rainier have_______.
Definition
flowed as far as tacoma within the last 5000 years
Term
What is the difference between relative and numerical dating?
Definition
relative dating uses stratigraphic principles and the fossil record to put deposits and events in order, numerical dating uses isotopic decay to determine the age.
Term
In metamorphic rocks with foliation, the texture develops as a result of:
Definition
the alignment of platy (flat) minerals perpendicular to the maximum pressure on the body of rock.
Term
What diagnostic criteria did you use to identify sedimentary conglomerate:
Definition
large rounded clasts within the rock matrix
Term
Which of the following conditions on a slope will increase the likelihood of landslides?
Definition
increasing the slope angle, saturating the soil, increasing the weight on the slope, removing the vegetation on the slope (all of the above)
Term
which test could conclusively tell you that marble and limestone are both composed from the mineral calcite?
Definition
reaction with HCL acid
Term
monocline folds result from______
Definition
uni-directional stresses
Term
Pillow basalts form when basalt is______
Definition
erupted into water
Term
how can a geologist determine the source volcano of a dated ash layer in several local lake cores?
Definition
the ash layer will thicken in the lake cores closest to the source volcano, the grain size within the ash layer will increase in the lake cores closest to the source volcano (answers a and b)
Term
radiocarbon dating is most useful_____.
Definition
for dating organic matter less than 50,000 years old
Term
where is radiocarbon first produced on earth?
Definition
in the atmosphere
Term
a volcanic neck is formed______and the surrounding rock erodes away.
Definition
when a magma body solidifies within the vent of a volcano
Term
a high strain rate is conductive to_____deformation or rock
Definition
brittle fracture
Term
According to the national earthquake hazard map, the puget sound region is a______risk region of the nation.
Definition
High
Term
The_____is exposed in the center of an eroding anticline.
Definition
oldest rock
Term
a reverse fault
Definition
may have repeatedly strata exposed in a vertical cross-section, may result in older rock units overlying younger units in a vertical cross-section (only a & B)
Term
____is an example of elastic deformation
Definition
filling and emptying a reservoir, isostatic unloading of the earths lithosphere following deglaciation (answers b and c)
Term
Which metamorphic rock has been subject to the lowest grade of heat and pressure?
Definition
Slate
Term
What kind of faults bound mountains and valleys of the basin and range province in nevada and utah?
Definition
normal faults
Term
What kind of stress would you expect to cause normal faulting?
Definition
tensile
Term
At what kind of plate margin would you expect to find at a normal fault?
Definition
divergent
Term
What hypothesis did we discuss to explain basin and range tectonics.
Definition
the spreading ridge was subducted under california and is now positioned under nevada and utah
Term
overturned fold may evolve into_____
Definition
thrust faults
Term
the stress rate______the strain rate for elastic deformation
Definition
is proportional to
Term
Where do earthquakes occur in the pacific northwest?
Definition
Near the surface within the North american plate, deep within the juan de fuca plate, at the cascadia subduction zone (all of the above)
Term
The recurrence interval of large cascadia subduction zone earthquakes is_____
Definition
500 years
Term
As the northern great lakes isostatically rebound
Definition
drain south into Mississippi river
Term
An overturned fold will often evolve into a_____with continued compressive stress
Definition
thrust fault
Term
A Tabular intrusive body that is oriented parallel to the existing sedimentary strata______.
Definition
is a sill
Term
In metamorphic rocks with foliation, the texture develops as a result of:
Definition
the alignment of platy (flat) minerals perpendicular to the maximum pressure on the body of rock
Term
what diagnostic criteria did you use to identify sedimentary breccia?
Definition
large angular clasts within the rock matrix
Term
Bonus 1
Definition
green tea w/ raw sugar
Term
bonus 2
Definition
potters clay doesnt have shrink and expand properties --> kaylalvite
Term
bonus 3
Definition
K = calcium
Term
bonus 4
Definition
he used the other overhead b/c it was covered in writing
Term
bonus 5
Definition
best student = eager beaver
Term
bonus 6
Definition
main middle screen was up --> we used an overhead out of the floor
Term
bonus 7
Definition
terry just turned 49
Term
Which mineral group accounts for most of our extractable iron ore deposits in the world?
Definition
oxides
Term
Joints facilitate weathering because ________.
Definition
permit water and other chemical agents to penetrate below the surface, provide more surface area for the weathering front to attack (b & c)
Term
Why is olivine the dominant mineral in most beach sands?
Definition
olivine is not the dominant mineral in beach sands
Term
Which rock type will tend to produce sink holes in Florida from solution weathering?
Definition
Limestone
Term
Frost wedging would be most prominent in:
Definition
sub-polar latitudes where temperature fluctuate around the freezing temperature during certain seasons.
Term
Which soil horizon contains the highest organic content?
Definition
A horizon
Term
Spheroidal weathering occurs because:
Definition
rounding occurs because the edges and corners of the rock surface offer more points of attack to chemical
weathering processes than its planar surface
Term
Which of the following transport agents generally results in current (asymmetric) ripples?
Definition
wind, rivers (a & c)
Term
Why do geochronologists not use the ratio of 14C/14N to determine the age of organic matter?
Definition
Most of the 14N found in organic matter is naturally occurring and not the result of 14C decay.
Term
If a horizontal layer of volcanic tephra lies between two horizontal sedimentary strata, the principle by
which the relative ages of each of these layers could be determined is:
Definition
the principle of superposition
Term
According to the principle of inclusions:
Definition
a xenolith will be older than the plutonic body in which it is emplaced, clasts within a conglomerate will be older than the rock itself (a & c)
Term
According to the principle of cross-cutting relationships, if a fault is found cutting across sedimentary
strata, the reasonable conclusion would be that:
Definition
the fault is younger than the strata
Term
The half-life of a radioactive isotope refers to:
Definition
the time it takes for half of the existing parent isotopes to decay to daughter isotopes
Term
A nonfoliated metamorphic rock would likely form _________.
Definition
from contact of pre-existing country rock with an igneous pluton
Term
In order to relieve stress buildup that would cause a Richter magnitude 6 earthquake, approximately
how many magnitude 5 earthquakes would have to occur?
Definition
30
Term
An eroding anticline (upwarped fold) will have the __________ rocks exposed along its axis.
Definition
oldest
Term
A reverse fault _______________.
Definition
can have repeating strata exposed in a vertical cross-section, can result in older rock units overlying younger units in a vertical cross-section, results primarily from compressive stresses. (all of the above)
Term
________________ is an example of elastic deformation.
Definition
subsidence related to the filling of a reservoir, isostatic unloading of the earth's lithosphere following deglaciation (b & c)
Term
What type of faulting would you expect to dominate the Canadian Rockies or Appalachian Mountains?
Definition
thrust faults
Term
______________ is an example of elastic deformation.
Definition
isostatic unloading of the earth's lithosphere following deglaciation
Term
In the geologic time lab we studied _______ fossil assemblages that we used as biostratigraphic indicators?
Definition
3
Term
In metamorphic rocks with foliation, the texture develops as a result of:
Definition
the alignment of platy (flat) minerals perpendicular to the maximum pressure on the body of rock.
Term
In the sedimentary rock lab which chemical precipitate did we not observe in the laboratory?
Definition
bauxite
Term
In laboratory you used the first arrival time of P-waves to determine the distance between a seismic
station and the focus of the Nisqually earthquake. What is the most likely reason that the three arcs not
intersect at location one point, assuming your measurements were accurate?
Definition
the Nisqually earthquake focus was 50 km below the surface and the arcs would not intersect at the surface.
Term
All of the following types of weathering reduce the size of rocks without changing their chemical makeup except:
Definition
hydrolysis
Term
Where is chemical weathering most dominant:
Definition
tropical climates
Term
A_______facing slope in the Puget Lowland would tend to have the strongest soil development.
Definition
southerly
Term
A_______facing slope in Phoenix, Arizona would tend to have the strongest soil development.
Definition
northerly
Term
the A horizon of soil______.
Definition
is the zone of removal, tends to be darker in color than the underlying horizons, contains humus (decomposed organic matter) (all of the above)
Term
As soil age increases________.
Definition
the horizon profile becomes thicker, clay content in the B horizon increases, the soil becomes redder (all of the above)
Term
The greatest risk from Mt. Rainier is from_______.
Definition
lahar flows
Term
frost wedging would be most prominent in:
Definition
mid-latitude regions where temperature fluctuate around the freezing temperature during certain seasons
Term
the single most important factor controlling chemical weathering processes is:
Definition
water
Term
the dissolution of limestone to form caves results from water combining with:
Definition
carbon dioxide to form carbonic acid
Term
symmetric ripple form from_______.
Definition
wave oscillation
Term
spheroidal weathering occurs because:
Definition
rounding occurs because the edges and corners of the rock surface offer more points of attack to chemical weathering processes than its planar surface
Term
which of the following transport agents generally results in the most poorly sorted sediment?
Definition
glaciers
Term
which of the following statements about graded bedding is true?
Definition
graded bedding occurs because heavier particles tend to settle out of water faster than lighter particles, graded bedding might occur where a submarine landslide deposits sediment along the continental slope (a & c)
Term
which of the following statements about the process of cementation is not true?
Definition
fine-grained sediments (silt & clay) are more likely to be cemented together than coarse grained sediments (sand and graveis)
Term
clastic sedimentary rocks are composed predominately of:
Definition
silicate minerals
Term
If you saw a sequence of sedimentary strata exposed in the wall of the Grand Canyon that had conglomerate at the base, overlain by sandstone, shale and then limestone, you might infer that relative sea level was_______over geologic time:
Definition
rising
Term
the main difference between a breccia and a conglomerate is:
Definition
particle shape
Term
According to the principle of uniformitarianism, all of the following are true except:
Definition
the rate at which geological processes occur has always remained constant throughout geologic time
Term
if a horizontal layer of volcanic tephra lies between two horizontal, sedimentary strata, the principle by which the relative ages of each of these layers could be determined is
Definition
the principle of superposition
Term
according to the principle of cross-cutting relationships, if a fault is found cutting across sedimentary strata, the reasonable conclusion would be that:
Definition
the fault is younger than the strata
Term
according to the principle of faunal succession
Definition
very old rocks would contain fossils of only complex organisms, while younger rocks would contain fossils of both simple and complex organisms
Term
if you know the number of existing parent and daughter atoms (assuming the number of initial daughter atoms is zero) in a mineral, you can determine:
Definition
the number of initial parent atoms
Term
the half life of a radioactive isotope refers to:
Definition
the time it takes for half of the existing parent isotopes to decay to daughter isotopes
Term
the direction of stress resulting in a monocline is______
Definition
undirectional (one)
Term
a shield volcano is formed of alternating layers of_______.
Definition
basaltic lava flows
Term
Carbon 14 works best on:
Definition
organic material less than 60,000 years old
Term
if an earthquake occurs, the_____waves are the first to arrive at the seismic station.
Definition
P
Term
earthquakes measuring 3 and 5 on the richter scale differ in energy released by
Definition
900 times
Term
in order to relieve stress buildup that would cause a richter magnitude 7 earthquake, approximately how many magnitude 4 earthquakes would have to occur?
Definition
27,000
Term
a low strain rate is conducive to_______deformation in rock
Definition
elastic or ductile
Term
a reverse fault________.
Definition
can have repeating strata exposed in a vertical cross-section, can result in older rock units overlying younger units in a vertical cross section, results primarily from compressive stresses (all of the above)
Term
an eroding anticline(upward fold) will have the_______rocks exposed along its axis
Definition
oldest
Term
___________is an example of elastic deformation
Definition
isostatic unloading of the earths lithosphere following deglaciation
Term
the salinity of the ocean method underestimates the age of the earth because_________
Definition
oceans are younger than the earth itself, runoff and salinity input into the oceans has been variable over geologic time, much of the oceans salt is precipitated and does not impact the current oceans salinity
Term
Why did lord Kelvin underestimate the age of the earth using the earths heat loss over time
Definition
lord kelvin didnt know about natural radioactive decay and did not compensate for that heat source
Term
Why is East Africa so high?
Definition
upwelling of the asthenosphere is heating the base of the rifting continent at this location
Term
where do we find goethite and hematite together in a soil?
Definition
where the water table fluctuates near the surface
Term
what is the most common mineral in igneous rocks near the surface of earth?
Definition
feldspars
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