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GEOSCI001 Final
Final Exam
172
Geology
Undergraduate 2
12/13/2010

Additional Geology Flashcards

 


 

Cards

Term
Age Of the Earth
Definition
4 billion years
Term
two most common elements in the earth's core
Definition
Fe and Ni
Term
how deep is the mantle under State College
Definition
25 km
Term
highest seismic risk
Definition
memphis
Term
rates of sea-floor spreading at mid-ocean ridge
Definition
1-10 cm/year
Term
hot spot
Definition
A mid-plate mantle thermal anomaly that causes volcanism
Term
accretionary prisms
Definition
A thick pile of sediment shed off a volcanic arc and deposited next to the trench
Term
deepest places in the ocean basins
Definition
trenches
Term
how is basalt formed
Definition
From dry melting of peridotite in the upper mantle
Term
failed rift
Definition
The arm of a triple junction in which spreading ceases
Term
most common minerals in crustal rocks
Definition
silicates
Term
typical temperature of erupting basalt
Definition
1200 degrees celsius
Term
dike
Definition
A vertical sheet-like igneous intrusion
Term
granite
Definition
A coarse-grained acidic (high in silica) rock
Term
typical geothermal gradient in the crust and upper mantle
Definition
20-25 degrees celsius/km
Term
pyroclastic rock
Definition
A rock made of material blown out of a volcano
Term
where does evaporite form
Definition
In highly saline water bodies
Term
environment where the poorest sorted sediment is found
Definition
glacial valleys
Term
indicative of high energy deposition
Definition
cross bedding
Term
lahars
Definition
Volcanic mudflows
Term
when most deadly eruptions occur
Definition
When the magma system empties
Term
How were most people killed during the AD79 eruption of Vesuvius
Definition
A nuee ardente
Term
period before silurian
Definition
ordovician
Term
last stage of global conveyor belt
Definition
gulf stream
Term
coldest deep water in the ocean found here
Definition
off the coast of antarctica
Term
what causes upwelling
Definition
Offshore winds blowing surface water offshore
Term
As sea level rises, which way do barrier islands migrate over time
Definition
landward
Term
results from rising sea level
Definition
fjords
Term
braided river channel
Definition
A channel divided by multiple gravel bars
Term
may be used to estimate 100 year flood level
Definition
discharge
Term
why deltas form
Definition
River water enters the ocean, slows down and deposits load
Term
water table
Definition
The boundary between the undersaturated and saturated zones
Term
artesian spring
Definition
A natural spring that flows vertically upward
Term
creep
Definition
Imperceptibly slow down slope movement of material
Term
oldest evidence of life
Definition
3.8 billion years
Term
correct order of evolution
Definition
FISH, AMPHIBIANS, REPTILES, BIRDS
Term
Where was the massive volcanic eruption that likely triggered the P/T extinctions
Definition
Siberia
Term
obliquity
Definition
The tilt of Earth’s axis with respect to the orbital plane
Term
glacier accounts for most of the ice on Earth
Definition
ice sheet
Term
shape of glacial valleys
Definition
U-shaped
Term
moraine
Definition
Material deposited under and in front of a glacier
Term
Which isotope is concentrated into plants via photosynthesis
Definition
C-12
Term
Which isotope is concentrated in ice via evaporation
Definition
C-12
Term
evidence for warming in the Paleocene-Eocene thermal maximum (PETM; 55 Ma)
Definition
O-isotopes
Term
groups of animals appeared during the PETM
Definition
primates
Term
marine group suffered major extinctions during the PETM
Definition
Benthic foraminifera
Term
particularly sensitive to melting
Definition
ice shelves
Term
Approximately how much will global sea level rise if all of the ice on Antarctica were to melt
Definition
70 meters
Term
Approximately how much will global sea level rise if all of the ice on Greenland were to melt
Definition
6 meters
Term
informal name of the temperature curve for the last 1000 years
Definition
hockey stick
Term
Pangea
Definition
A supercontinent that existed about 250 million years ago
Term
origin of the Earth’s magnetic field
Definition
Motions of fluid iron in the outer core
Term
aesthenosphere
Definition
The partially molten layer comprising the upper mantle between 100 and 350 km depth
Term
thickness of the crust under the Himalayas
Definition
80 km
Term
Convergent boundaries
Definition
Places where two plates move towards one another
Term
associated with subduction zones
Definition
Trenches
Term
back arc basins
Definition
Basins that lie between island arcs and the continent
Term
triple junctions
Definition
Three-armed rift systems formed in the early stages of rifting
Term
formed by a hotspot
Definition
hawaii
Term
How did the Himalayan Mountains form
Definition
Collision of India and Eurasia
Term
formula of calcite
Definition
CaCO3
Term
How is granite generated most commonly
Definition
Partial melting of continental crust
Term
What minerals are typically found in a granite
Definition
Quartz, mica, K-feldspar and amphibole
Term
Porphyritic texture
Definition
large phenocrysts in a fine-grained groundmass
Term
batholith
Definition
a large body made of plutonic igneous rock
Term
limestone
Definition
A biogenic rock made up of CaCO3 fossils
Term
Where do turbidity currents occur
Definition
Down the continental slope
Term
evaporite
Definition
a sedimentary rock formed of salts evaporated from seawater
Term
Typically how long does a typical metamorphic rock take to form
Definition
Thousands to millions of years
Term
shield volcano
Definition
A broad, gently-sloped volcano built of basalt
Term
largest eruptions known
Definition
Ring dike
Term
How were most people killed after the 1883 eruption of Krakatoa
Definition
Tsunami
Term
geyser
Definition
A hot spring from groundwater heated by hot rock
Term
can be used to predict volcanic eruptions
Definition
Seismic activity
Term
How fast does a tsunami travel?
Definition
800 km/hr
Term
cratons
Definition
The old, cold part of continents
Term
brittle
Definition
Ruptures during deformation
Term
biostratigraphy
Definition
Use of fossils to correlate rocks
Term
slump
Definition
Downward and outward movement of material
Term
river terraces
Definition
Old floodplains elevated when the river cuts down to a new level
Term
How do ox-bow lakes form
Definition
When a river meander gets so tight, it cuts itself off
Term
longshore drift
Definition
A current that runs parallel to the coast
Term
till
Definition
Poorly sorted material deposited by glaciers
Term
cirque
Definition
A bowl-shaped depression in which a glacier originates
Term
kettle hole
Definition
A depression formed when a large piece of ice melts
Term
terminal/end moraine
Definition
A long hill of till deposited in front of a glacier
Term
permeability
Definition
a measure of the ability to transmit fluids
Term
aquifer
Definition
Body of permeable rock through which groundwater moves
Term
causes saltwater incursion
Definition
Major overuse of aquifers in coastal cities
Term
[image]
Definition
lahar
Term
[image]
Definition
nuee ardente
Term
[image]
Definition
alluvial fan
Term
[image]
Definition
barrier island
Term
[image]
Definition
basalt
Term
[image]
Definition
black smokers
Term
[image]
Definition
breccia
Term
[image]
Definition
esker
Term
[image]
Definition
gneiss
Term
[image]
Definition
granite
Term
[image]
Definition
pillow lava
Term
[image]
Definition
pyroclastic rock
Term
eccentricity
Definition
Shape of the Earth’s orbit
Term
What is the period of the precession cycle?
Definition
20,000 years
Term
used to reconstruct ancient climates
Definition
tree rings
Term
What was the likely trigger of the PETM?
Definition
Dissociation of methane hydrate
Term
How long would it take a surface wave to travel from San Francisco to State College
Definition
33 minutes
Term
What is the largest measured earthquake
Definition
9.5
Term
dilatancy
Definition
Minute cracking of ground from increased strain
Term
produces marble during metamorphism
Definition
limestone
Term
migmatite
Definition
Rock formed by a mixture of melting and metamorphism
Term
why is apparent polar wander apparent
Definition
continents are drifing
Term
what is the contiuous side of Bowen's reaction series
Definition
Ca-rich to Na-rich plahioclase feldspar
Term
process that will never be involved in the formation of a clastic sedimentary rock
Definition
evaporation
Term
processes involved in formation of clastic sedimentary rock
Definition
glacial transport, river transport, weathering, storms
Term
what represents the lowest energy out of conglomerate, mudstone, sandstone, or siltstone
Definition
mudstone
Term
will ice or wind produce the most well sorted sediment
Definition
wind
Term
processing during diagenesis
Definition
compaction, oxidation of organic matter, dewatering, formation of cement
Term
what does the presence of varves tell you
Definition
seasonal alternations in depostition in a lake
Term
temperature divide between diagenesis and metamorphism
Definition
200 degrees celsius
Term
texture of schist
Definition
a wavy rock with prominent sheen produced by mica
Term
if we metamorphose mudstone and limestone at medium temperature and pressure, what would the resulting rocks be
Definition
schist and marble
Term
role of water in metamorphism
Definition
speeds it up
Term
role of water in metamorphism
Definition
speeds it up
Term
what volcanic hazard would make you the most nervous
Definition
an active volcano covered with large amounts of ice
Term
why was the 1985 mexico city quake so destructive
Definition
the city lies on ancient lake bed
Term
hidden fault
Definition
faults that do not intersect the earth's surface
Term
low velocity zone corresponds to
Definition
the uppermost aesthenosphere
Term
reverse fault
Definition
a fault in which the hanging wall has moved upward
Term
where are reverse faults most likely to be forming today
Definition
the himalayas
Term
which period came before the cretaceous
Definition
the jurassic
Term
how C-14 is produced
Definition
bombardment of N-14 by cosmic radiation
Term
what was the imprtance of stromatolites in Earth's environmental evolution
Definition
their proliferation led to an increase in atmospheric oxygen
Term
why were extinction events important from an evolutionary point of view
Definition
they opened up large numbers of niches that could be filled
Term
what is an arguement for meteorite impact at the Permian-Triassic boundary extinctions
Definition
tiny piece of meteorite found at the boundary
Term
in what materials is Ir most enriched
Definition
meteorites
Term
what is the cause of the gravity anomaly at Chicxulub
Definition
melt rocks
Term
what were involved in the cause of the Cretaceous-Tertiary boundary extinctions
Definition
starvation, darkness, acid rain
Term
where may ice shelves be located
Definition
off the coast of antarctica
Term
where would you expect to find a spring
Definition
a hillside where limestone overlies mudstone
Term
what is a hazard of over-use of an aquifer
Definition
land subsidence
Term
what formed last our of nova, nebula, or planets
Definition
planets
Term
what is true about fluids emanating from black smokers
Definition
they are very hot and metal rich
Term
why do seismic waves slow down in the low velocity zone
Definition
the material is partially molten
Term
what might you conclude from a coal overlain by beach sand
Definition
sea level is rising
Term
where would you most ecpect to find metamorphism occuring
Definition
in active mountain building
Term
most significant factor in causing fatalities during the Great Sumatra Quake
Definition
the epicenter was under water
Term
how long would it take a P wave to travel from Los Angeles to State College
Definition
13 minutes
Term
why is weathering relevant for modern global warming
Definition
silicate weathering can reduce atmospheric CO2
Term
Morocco and Florida are at similar latitude and opposite sides of the north atlantic, which has warmer surface water
Definition
florida
Term
was subaerial during the ice age
Definition
continental shelf
Term
where would be the best place to drill a well
Definition
well-sorted sandstone
Term
what is a significant groundwater issue in miami
Definition
saltwater incursion
Term
why does fire increase the risk of mass wasting
Definition
it removes plants that hold slopes together
Term
what do fossils of the earliest cells look like
Definition
segmented chains
Term
when did the diversity of mammals increase most rapidly
Definition
after the cretaceous/tertiary boundary
Term
which gas was a likely killer at the permian/triassic boundary
Definition
H2S
Term
what ecosystems suffered the least extinctions at the cretaceous-tertiary boundary
Definition
deep ocean
Term
what is evidence that the asteroid trajectory was from S to N
Definition
burnt plants in north america are evidence of a giant fireball
Term
what is the diameter of the Chicxulub crater
Definition
180 km
Term
what would halt ice advance immediately
Definition
drought
Term
under which conditions would glaciers surge
Definition
accumulation >> ablation
Term
which isotope is concentrated in ice via evaporation
Definition
O-16
Term
what is the fundamental evidencefor the Snowball Earth
Definition
glacial sediments depostited at low altitudes
Term
what is the age of the Snowball Earth
Definition
1.5 billion years
Term
what is a factor for the intiation/occurrence of Snowball Earth
Definition
clustering of continetns at low altitudes
Term
what likely caused the warming that ended the snowball
Definition
build up of volcanic CO2
Term
where did organisms survive the snowball
Definition
at the base of thin ice or within the ice
Term
what caused the cretaceous oceans to be prone to anoxia
Definition
warm temperatures
Term
what was the most likely source of greenhouse gas for the PETM
Definition
gas hydrate
Term
what is an integral part of predicting future climate
Definition
climate models
Term
which region of the US is subject to major drought in the next century with continued warming
Definition
the midwest
Term
why is the ozone hole no longer growing
Definition
countries have cut down on chloroflourocarbon emission
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