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326 Cards in this Set

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What type of weathering is accomplished by physical forces that break rock into smaller and smaller pieces without changing the rock's mineral composition?
mechanical weathering
When water in cracks and joints freezes and expands the rock is broken into angular fragments. This process is known as _____ ________. (two words)
frost wedging
Stone Mountain, Georgia, and Half Dome in Yosemite National Park are excellent examples of ________ domes.
exfolation
______ weathering alters the internal structures of minerals by removing and/or adding elements.
Chemical
The general rounding of the corners and edges of angular blocks of rock is termed _____ _______. (two words)
spheroidal weathering
The downslope movement of rock, regolith, and soil under the direct influence of gravity is called _____ _______. (two words)
mass wasting
Loose particles assume a stable slope called the _____ __ ______ (3 words), the steepest angle at which material remains stable.
angle of repose
________ occurs when material usually saturated with water moves downslope as a viscous fluid.
flow
The most rapid form of mass wasting is termed a ___ _________ (two words).
rock avalanche
The downward slipping of a mass of rock or unconsolidated debris moving as a unit along a curved surface is called _________.
slump
Events along Wyoming's Gros Ventre River (1925) represent an excellent example of _________.
rockslide
Mudflows that occur on the slopes of some volcanoes are known as ______.
lahars
The destructive mudflows at Nevado del Ruiz in 1985 are also known by the Indonesian term _____.
lahar
The most important weathering process is what?
unloading
What are three facts about sheeting?
-caused by unloading
-can produce exfoliation domes
-commonly associated with large bodies of granite
In what kind of climate would chemical weathering be most effective? (temperature, moisture)
in a warm, humid climate
What are three examples of the products of chemical weathering of the mineral potassium (K) feldspar?
silica, potassiu bicarbonate, and clay
What sedimentary rock is composed of the most abundant product of chemical weathering?
shale
If granite and basalt outcropped in an area with a hot humid climate, what rock would weather faster, or both?
the basalt would weather quicker
Which type of weathering would predominate...(if granite and basalt outcropped a hot and humid area)?
chemical weathering
What is one true fact about mechanical weathering and its effect on metamorphic rocks?
it does not affect them
The incorporation and transportation of material by water, wind, or ice describes the process of...?
erosion
When water freezes, does its volume increase or decrease?
increase
An accumulation of angular rock fragments at the base of a steep cliff is called?
talus slope
Which of the locations would frost wedging be most effective?
-Amazon Basin of Brazil
-Chicago, Illinois
-north (Arctic) coast of Alaska
-frost wedging should be equally effective at all of these places
Chicago, Illinois
What factors influence the type and rate of weathering?
-mineral content
-climate
-presence of joints
-topography
Bauxite has an ore of...
aluminum
Bauxite formation is associated with what?
rainy, tropical climates
What factors contributed to the Gros Ventre rockslide?
-strata were dipping
-a layer of clay was present
-there were heavy rains and melting snow
What terms describe what happens in a mass wasting event? (3 terms)
fall, slide, flow
What is the controlling force of mass wasting?
gravity
Solifluction is common during...?
summer
A rapid form of flowage that is common in dry regions is?
mudflow
Alternate wetting and drying or freezing and thawing leads to what?
creep
What occurs when a tongue of clay-rich material flows downslope in a humid region?
earthflow
True/False: Cleopatra's Needle, a granite obelisk moved to New York City from Egypt, illustrates that the rate of chemical weathering in New YOrk is much more rapid than in Egypt.
True
True/False: Cleopatra's Needle, a granite obelisk moved to New York City from Egypt, illustrates that granite weathers more rapidly in a dry climate.
False
True/False: Sheeting results from unloading
true
True/False: Sheeting most commonly affects large igneous masses composed of granite.
true
True/False: Sheeting is an especially important weathering process affecting thinly-bedded sedimentary rocks such as shale.
False
True/False: Chemical weathering is ineffective in polar regions.
True
True/False: Chemical weatheirng does not occur in arid regions.
False
True/False: Sheeting is a mechanical weathering process.
True
True/False: Thermal expansion is the most important process in the formation of an exfolation dome.
False
True/False: Quartz is very resistant to chemical weathering.
True
True/False: Clay minerals are a product of chemical weathering.
True
True/False: The order in which the silicate minerals chemically weather is opposite their order of crystallization.
False
True/False: Water is basic to all mass wasting processes.
True
True/False: Slump is an imperceptibly slow, downhill flow of soil.
False
True/False: Solifluction is definitely more common in Alaska than in Florida.
True
True/False: Mudflows are most common in semiarid mountainous regions.
False
True/False: Mudflows are equally common in humid and dry regions.
True
True/False: Gravity plays an important role in all mast wasting events.
True
True/False: The Gros Ventre slide of 1925 has recently been reclassified as a lahar.
False
True/False: Slump is the most rapid form of mass wasting.
False
True/False: Mass wasting has played an important role in forming the Grand Canyon.
True
True/False: Lahars occur in association with volcanoes.
True
True/False: Earthflows are most common in arid and semiarid regions.
False
True/False: The freezing and thawing of soil can produce a gradual downhill movement of material.
True
True/False: Mudflows that accur when layers of volcanic ash become saturated are termed solifluction lobes.
False
Another name for the Ice Age is:
the Pleistocene epoch
What are the glacial stages of the Ice Age in order from first to last?
Nebraskan, Kansan, Illinoian, Wisconsinan
How does an alpine glacier modify the valley through which it moves?
it straightens it
What are three characteristics of continental glaciation moraines?
-terminal moraine
-ground moraine
-recessional moraine
What are three true facts about glacial deposits?
-drift refers to any glacial deposit
-stratified drift is deposited by meltwater
-erratics are rocks deposited by a glacier
What is a fiord?
a drowned glacial trough
Give one true fact about drumlins
they are found in clusters (groups)
If the steep side of a drumlin is on the northeast, it indicates that the glacier advanced from what direction?
southwest
what feature is created when two lateral moraines join?
medial moraine
During the most recent ice age, what percentage of the earth did glaciers cover?
30%
What are three indirect effects of glaciers?
-extinction of organisms
-changes in river courses
-formation of pluvial lakes
What percent of the earth's land surface is covered by ice sheets?
10%
What are three glacial erosion effects or processes?
-glacial striations
-plucking
-abrasion
In North America, the greatest concentration of pluvial lakes existed in:
the Basin and Range region of Utah and Nevada
Who proposed the astronomical theory of the Ice Age climatic fluctuations?
Milankovitch
What three factors may have contributed to the climatic changes related to the Ice Age?
-plate movement
-wobbling of the earth's axis
-variations in the shape of the earth's orbit
A layer of till deposited as the front of a glacier retreats is called a(n):
ground moraine
What is a streamlined asymmetrical hill composed of till?
drumlin
A broad accumulation of stratified drift deposited adjacent to the downstream edge of an end moraine is a(n):
outwash plain
A long and narrow sinuous ridge composed of sand and gravel is:
an esker
How does wind transport sand grains?
by saltation as part of the bed load
Desert pavement is a result of:
deflation
The slip face of a particular barchan dune is on the southeast side. The prevailing wind in this area is from the:
northeast
Which stage of landscape evolution in a mountainous desert is relief greatest?
early stage
Inselbergs are:
erosional remnants on an old age desert landscape
Desert and steppe regions cover what fraction of the earth's land surface?
1/3rd
What percent of the desert's surface is covered by sand dunes?
60%
A wash is:
a desert stream channel
What are three types of wind erosion?
-deflation
-blowout
-slip face
Blowouts are most common in the: (it's a place)
Great Plains
What is a place that represents the late stage of the evolution of a mountainous desert landscape?
southern Arizona
How high can the surface can sand be carried during very strong winds?
one meter
Dunes whose tips point into the wind are:
parabolic dunes
Often form along coasts where strong winds create a blowout: (a type of dune)
parabolic
Solitary dunes whose tips point downwind are:
barchan dunes
Sand ridges oriented at right angles to the wind are:
transverse dunes
Long sand ridges that are pointed more or less parallel to the wind are:
longitudinal dunes
True/False: Even when the front of a glacier is retreating, the ice withing the glacier is advancing.
True
True/False: crevasses form in the zone of fracture.
True
True/False: When accumulation exceeds ablation, the front of the glacier advances.
True
True/False: Till is sediment deposited directly by a glacier.
True
True/False: Except for their relative positions, terminal and recessional moraines are essentially alike.
True
True/False: Melting is a form of ablation.
True
True/False: Glaciers cannot erode below sea level.
False
True/False: The Hudson Bay region has been gradually subsiding (sinking) since the close of the Ice Age.
False
True/False: The Pleistocene eopch is the only glacial period for which evidence exists.
False
True/False: Many scientists believe that the plate tectionics theory offers the best explanation for the alternation glacial and interglacial climates of the Ice Age.
False
True/False: Greenland's ice sheet is about equal in sizee to Antarctica's.
False
True/False: A cirque is the primary sone of ablation for alpine glaciers.
False
True/False: The coasts of Norway, Chile, and Alaska all exhibit fiords.
True
True/False: Sea level does not act as base level for glaciers.
True
True/False: Ice Age glaciers covered more lan din North America than in Siberia.
True
True/False: Louis Agassiz proposed the astronomical theory of Ice Age climatic fluctuations.
False
True/False: The Matterhorn is an excellent example of an arete.
False
True/False: Fiords are found exclusively along the coast of Norway.
False
True/False: All of Wisconsin is characterized by relatively thick glacial deposits.
False
True/False: Moraines are the only glacial deposits composed of till.
False
True/False: Running water is the most important erosional agent in arid regions.
True
True/False: The geological processes (forces) operating in deserts are quite different than those operating in humid regions.
False
True/False: Loess deposits are more blanket-like whereas deposits of wind-blown sand are more commonly in the form of mounds or ridges.
True
True/False: Arid and semiarid climates cover nearly one-third of the earht's land surface.
True
True/False: The Basin and Range region of the western US is an excellent example of a mountainous desert landscape.
True
True/False: A playa is a dry, flat lake bed on the floor of a desert basin.
True
True/False: The Colorado River is an example of a large wash.
False
True/False: Loess deposits usually take the form of dunes.
False
True/False: Except for some scattered accumulations in Alaska, loess deposits are not present in the US.
False
True/False: Blowouts are shallow depressions caused by deflation.
True
True/False: Desert pavement results from deflation.
True
True/False: Desert pavement protects a surface from deflation.
True
True/False: The windward slope of a sand dune is known is a slip face.
False
True/False: The famous Navajo Sandstone exposed in Zion National Park shows excellent cross bedding.
True
True/False: Longitudinal dunes are oriented at right angles to the prevailing wind whereas transverse dunes are more or less parallel to the prevailing wind.
False
True/False: THe predominant particle size in loess deposits is silt.
True
The upper 50 meters or so of a glacier consists of brittle ice that often exhibits cracks called ______.
crevasses
The upper 50 meters or so of a glacier is britlle and referred to as the zone of ______.
fracture
The general term for the wastage of glacial ice is __________.
ablation
Glaciers erode on the land and primarily in two ways. List these two processes.
abrasion and plucking
Bridalveil Falls in Yosemite National Park cascades a feature called a ________ _________. (two words)
hanging valley
The bowl-shaped depressions at the head of glaciated valleys are termed _______.
cirques
The word ____ is an all-embracing term for sediments of glacial origin.
drift
Glacial deposits are divided into two distinct types: ______ and ___________ _________. (three words, but two terms)
till, stratified drift
An _____ ________ is a ridge of till that forms at the terminus of both alpine and continental glaciers. (two words)
end moraine
A gently rolling layer of till laid down as the front of a glacier retreats is termed _______ _________. (two words)
ground moraine
Smooth, elongate hills composed of till called __________ have a steeper slope that faces the direction of glacial ice advance.
drumlins
Depressions called ______ are found when a block of stagnant ice becomes buried in drift and then melts.
kettles
Most of the recent Ice Age occurred during the __________ epoch.
Pleistocene
Desert stream courses, which are usually dry, are known as ________.
washes
The lifting and removal of loose material by wind is called ________.
deflation
The main factor that controls the depth of a blowout is ____ _________. (two words)
water table
As deflation lowers the surface by removing sand and silt, eventually a continuous cover of coarse particles known as ________ _________ remains. (two words)
desert pavement
The leeward slope of a dune, called the ________ ________, maintains an angle of about thirty-four degrees.
slip face
The sloping layers within a sand dune are called ____ ____. (two words)
cross bed
What are four basic dune types?
barchan, transverse, longitudinal, and parabolic
Dunes whose tips point into the wind are ________ dunes.
parabolic
Deposits of windblown silt are known as _____.
loess
What is the source of the energy that radiates in all directions from an earthquake?
focus
An earthquake with a magnitude of 6.5 on the Richter scale releases about ____ times more energy than one with a magnitude of 5.5.
30
What is the term used to describe what occurs to produce an earthquake?
elastic rebound
The Mercalli scale rates earthquake intensity by determining:
the amount of damage to structures
The amount of destruction caused by earthquake vibrations is affected by:(three factors)
-the design structures
-the intensity and duration of the vibrations
-the nature of the surface
The method of using a seismograph to establish the strength of earthquakes wasd developed by:
Charles Richter
Major earthquakes are often followed by somewhat smaller events known as:
aftershocks
The instrument which records earthquake events is termed a:
seismograph
Most strong earthquakes occur in a zone known as the:
circum-pacific belt
What is the type of measurement used to describe the quantity of energy released by an earthquake
magnitude
The position on the earth's surface directly above the earthquake source is called:
epicenter
The mechanism by which rocks store and eventually release energy in the form of an earthquake is termed:
elastic rebound
The study of seismology dates back to when?
the ancient chinese
The principle of the seismograph is based on:
the inertia of a suspended mass
What seismic wave is the most destructive overall?
surface waves
An increase of one unit of magnitude on the Richter scale equates to about a:
30-fold increase in energy
What seismic wave travels the most rapidly?
P waves (primary)
At 6.5 Richter magnitude earthquake releases _____ times more energy than a 4.5 Richter magnitude earthquake.
900
Considering its distance from the source of the September 19, 1985 earthquake, Mexico City was damaged more than might be expected because:
the unconsolidated sediments on which the city was built intensified the vibrations
Following the 1964 Alaskan earthquake, much of the destruction was attributed to:
numerous ground failures and landslides
What are two names that are the correct term for the succession of ocean waves set in motion by a submarine earthquake called?
tsunami or seismic sea waves
The distance between a seismological recording station and the earthquake source is determined from what?
the arrival time of P and S waves
The record obtained from seismic instruments of an earthquake is called:
seismogram
The slow continual movement which occurs along some fault zones is termed:
creep
Most of our knowledge about the earth's interior comes from:
seismic waves
The discovery of the shadow zone provided evidence for what?
the existence of a core.
The dense core of the earth is thought to consist mostly of:
iron
The thinnest layer of the earth is the:
crust
S waves are not transmitted through this layer.
inner core
The densest layer of the earth is the:
inner core
The lithosphere is defined as:
a rigid layer of crustal and mantle material
The Moho is the boundary between the: (two layers it is the boundary between)
mantle and crust
The average composition of the upper mantle is thought ot approximate that of:
peridotite
The average composition of the oceanic crust is thought to approximate that of:
basalt
The average composition of the continental crust most closely approximate that of:
granite
The astenosphere is located:
in the upper mantle
True/False: Since San Francisco has already experienced a very destructive earthquake (1906), it is not likely to experience another.
False
True/False: During the 1964 Alaskan earhtquake, structures which has been built to conform to the earthquake provisions of the Uniform Housing Code of California went undamaged.
False
True/False: Seismographs can only detect earthquakes within 500 miles of the instrument.
False
True/False: During the 1964 Alaskan earthquake, landslides and ground subsidence probably caused more damage to buildings than was caused directly by the vibrations of the earth.
True
True/False: The adjustments which follow a major earthquake often generate small earthquakes called foreshocks.
False
True/False: The epicenter is the location on the earth's surface directly above the focus.
True
True/False: An increase of one on the Richter scale corresponds to a tenfold increase in the amplitude of surface waves.
false
True/False: An earthquake is the vibration of the earth produced by the rapid release of energy.
True
True/False: The energy released during an earthquake can be detected for at most a few minutes.
False
True/False: Most major earthquakes are followed by smaller tremors, some of which can be destructive to already weakened structures.
True
True/False: When examining a typical seismic record, we expect to find surface waves arriving before body waves.
False
True/False: S waves can only travel through a solid medium.
True
True/False: P waves can travel through solids, liquids, and gases.
True
True/False: Travel-time graphs are used to determine the distances to earthquakes.
True
True/False: A total of 1,000 earthquakes are estimated to occur worldwide each year.
False
True/False: All of the major earthquakes in the United States have occurred in coastal regions.
False
True/False: It is now possible for seismologists to predict an earthquake to withing a few weeks or at most a few months of its occurrence.
False
True/False: Faults which are not experiencing active creep are considered safe.
False
True/False: Generally speaking, brick structures are far more resistant to earthquake damage than are wood frame buildings.
False
True/False: During the 1906 San Francisco earthquake, much of the destruction was caused by fires which ran unchecked because of damaged water lines.
True
True/False: There are several reliable methods of short-range earthquake prediction.
False
True/False: The outer core is solid and the inner core behaves as a liquid.
False
True/False: The continental crust is much thicker than the oceanic crust.
True
True/False: Most of our knowledge about the earth's interior comes from deep-sea drilling.
False
True/False: Continental rocks are very similar in composition (mineral make-up) to ocean rocks.
False
True/False: The Moho is a boundary which seperates the mantle and crust.
True
True/False: The lithosphere is a plastic layer located in the mantle.
False
True/False: The composition of the upper mantle is thought to approximate that of the rock peridotite.
True
True/False: The oceanic crust has a composition similar to the rock basalt.
True
The mechanism of earthquake generation was discovered by ______ following the 1906 San Francisco earthquake.
Reid
Earthquakes frequently are associated with large fractures in the earth called ______.
faults
The source of an earthquake is known as the ______.
focus
The position at the earth's surface directly above the earthquake source is called the ________.
epicenter
The mechanism by which rocks store and eventually release energy to produce an earthquake is termed _____ ________. (two words)
elastic rebound
The greatest frequency of large earthquakes occur along a relatively narrow zone known as the ______ _________ ______. (three words)
circum-pacific belt
An earthquake is the vibration of the earth produced by the rapid release of ________.
energy
Which type of body wave can be transmitted through solids but not fluids?
S waves
The slow continual movement which occurs along some fault zones is termed _________.
creep
Seismic sea waves are also known by the Japanese name ________.
Tsunami
The method by which seismographs are used to determine the magnitude of an earthquake was developed by _________.
Richter
Major earthquakes are preceded by smaller seismic events known as ______.
foreshocks
The instrument used to record the vibrations generated by earthquakes is called a(n) ____________.
seismograph
The energy released by an earthquake is a measurment referred to as _________.
magnitude
The principle of a seismograph is based on the ___________ of a suspended mass.
inertia
Most of the destruction produced by earthquakes is associated with ______ waves.
surface
An increase of one unit of magnitude on the Richter scale means that the release of energy will be ____ times greater.
30
In addition to damage caused by vibrations, many buildings in San Francisco were destroyed during the 1906 earthquake by ____.
fire
The most voluminous layer of the earth is the _______.
mantle
The rigid layer of the earth which consists of the crust and uppermost mantle is termed the ________.
lithosphere
Which of the major subdivisions of the earht's interior is thought to be liquid?
outer core
List the major subdivisions of the earth's interior.
crust, mantle, outer core and inner core
The thinnest layer of the earth is the _______.
crust
The mobile layer of the earth located directly below the lithosphere is the ____________.
asthenosphere
The mineral composition of the oceanic crust is similar to the rock ________.
basalt
The dense core of the earth is thought to consist predominantly of _____.
iron
The boundary between the crust and the mantle is called the ________.
Moho
The man who pioneered the continental drift hypothesis was:
Alfred Wegener
Pangaea:
is the name of a supercontinent
The asthenosphere is the source of what at divergent boundaries?
magma
Geomagnetic reversals provided what?
evidence for sea-floor spreading
Plates move apart leaving a gap at:
divergent plate boundaries
Plates move together along:
convergent plate boundaries
New oceanic crust forms at:
divergent plate boundaries
Plates slide past one another at:
transform fault boundaries
Oceanic crust is destroyed along:
convergent plate boundaries
Oceanic crust is neither created nore destroyed along this type of boundary:
transform fault boundary
Island arcs are associated with: (be specific)
convergent (oceanic-oceanic) boundaries
The Red Sea was formed along a:
divergent boundary
Mount St. Helens is associated with a:
convergent (oceanic-continental) boundary
The Himalaya Mountains were produced along a:
convergent (continental-continental boundary)
San Andreas Fault exemplifies this type of boundary.
transform fault boundary
Iceland is located along:
divergent boundary
Japan is associated with this type of plate boundary.
convergent (oceanic-continental) boundary
The Mid-Atlantic Ridge is an example of a:
divergent boundary
The Aleutian Islands are the result of plate interaction at which type of plate boundary?
convergent (oceanic-oceanic) boundary
The African rift valleys are assocaited with a:
divergent boundary
The Andes mountains were generated at a:
convergent (oceanic-continental) boundary
Convergent boundaries are zones where plates:
move together, causing one to go beneath the other
Divergent boundaries are zones where plates:
move apart
It was learned from the Deep Sea Drilling Project that the oceans are:
oldest adjacent to the continents and youngest at the ridges
The continents fit together best in the Pangaea configuration when:
the outer edges of the continental shelves are matched
Wegener's suggestion that tidal forces might cause continental drift was shown untenable when:
the tidal forces required to move the continents would stop the earth's rotation in a matter of years.
Late Paleozoic continental glaciation provided important evidence favoring continental drift. This evidence was gathered from:
South America, Africa, Antarctica, and India
The true margin of a continent is:
the outer edge of the continental shelf
The island of Hawaii experiences volcanism because it is located:
above a hot spot
If you wanted to draw the boundaries of active lithospheric plates on a globe which would give you the most complete information?
a map showing earthquake distribution
The asthenosphere permits...
plate motion
The pattern of magnetic anomalies on the sea floor most resemble:
stripes on a zebra
When a dep oceanic trench is located adjacent to a continent, we would likely find active volcanoes where?
landward from the trench
The Hawaiian are located where the Pacific Plate is:
migrating over a hot spot
Hot spots are believed to originate:
as columns of hot material rising through the deep mantle
The geographic destribution of Mesosaurus, a small swimming reptile that lived during the late Paleozoic, provides evidence that
South America and Africa were once joined
Lithospheric plates are about how many kilometers thick?
100km thick
Deep ocean trenches are assocaited with:
subduction zones
The enrgy that causes plates to move is derived from:
the earth's internal heat
If the earth's magnetic field did not occasionally reverse polarity:
the sea floor would not produce magnetic stripes
In the plate tectonics model, the earth's outer shell consists of about _____ individual plates.
20
Much of the evidence in support of plate tectonics has come from:
the Deep Sea Drilling Project
How did the opponents of the continental drift hypothesis account for the existence of similar life forms on widely seperated landmasses?
migration across land bridges
Alfred Wegener's now famous book was first titled:
The Origin of Continents and Oceans
How many years passed from the time continental drift was first formally proposed until the concept was widely accepted?
about 50
When an iron-bearing mineral is heated above a certain temp, it loses its magnetism. This temperature is about: (in degrees Celsius)
580 degrees Celsius
When a rock is heated above a certain temperature is called the ____, it looses its magnetism.
Curie point
Subduction zones are assocaited with:
convergent plate boundaries
Most of the world's deep ocean trenches are located within the:
Pacific Ocean
True/False: The continents are older than the ocean basins.
True
True/False: Since oceanic crust is continually being produced, the size of the earth is increasing.
False
True/False: The island of Hawaii is the youngest of the Hawaiian Islands.
True
True/False: The oldest rocks in the ocean are near the mid-ocean ridges.
False
True/False: Measurements indicate that the west coast of Africa and the east coast of South America are getting closer together.
False
True/False: Continental crust is less dense than oceanic crust.
True
True/False: Sediments get thicker with increasing distance away from the mid-ocean ridges.
True
True/False: Periodically, the earth's magnetic field reverses, that is the northa nd south magnetic poles switch polarity.
True
True/False: The rate of the sea floor spreading avergaes about one meter (3 feet) per year.
False
True/False: A major criticism paleomagnetism indicate the direct of the magnetic poles at the time the rocks crystallized.
True
True/False: The positions of the magnetic poles correspond closely to the positions of the geographic poles.
True
True/False: Geomagnetic reversals represent a source of information on the rate of sea-floor spreading.
True
True/False: The information gathered by the Deep Sea Drilling Project was used to refute several important aspects of the plate tectonics theory.
False
True/False: The Himalayan Mountains were produced by a collision of India with Asia about 40 million years ago.
True
True/False: Iceland is located upon the Mid-Atlantic Ridge.
True
True/False: Wegener erroneously concluded that the glacial moraines of Europe matched up with similar features in North America.
True
True/False: The island of Hawaii experiences volcanism because it is located above the Mid-Pacific Ridge.
False
Instruments which measure the earth's magnetic field are called __________.
magnometer
The earth's present magnetic field is said to possess ______ polarity.
normal
At numerous times in the past of the earth possess a magnetic field opposite of that observed today. Rocks which exhibit this magnetism are said to have _____ polarity.
reverse
The vessel that operated during hte 1970's and early 1980's as part of the Deep Sea Drilling Project to provide evidence for plate tectonics was called the ________ ____________ (two words)
Glomar Challenger
The true nature of transform faults was provided by ____ _____ (two words).
Tuzo Wilson
What type of lava flow has a surface of rough, jagged blocks and sharp, angular projections?
aa lava flow
What is the most abundant gas associated with volcanic activity?
water vapor
In 1902, the town of St. Pierre was destroyed and its population of 28,000 killed because of:
an avalanche of incandescent volcanic ash and dust
Cinder cones:
-have very steep slopes
-are usually less than 300 meters high
-frequently occur in groups
-consist largely of pyroclastics
-all of the above
-all of the above
THe most violent activity is associated with:(what type of volcano?)
composite cones
The Columbia Plateau in the northwestern US is an excellent example of:
flood basalts
The oceanic ridge system is the major site of:
-spreading center volcanism
-formation of magma by partial melting of mantle rocks
-formation of basaltic magma
-all of the above
all of the above
Kilauea is an example of a:
shield volcano