Exam 2 quizzes Flashcards
ch. 9 - Major sources of water in the continental hydrologic comes from
- evaporation from oceans at 20 to 40 degrees north and south
What is the major source of water that falls as precipitation in the southeastern United States?
- the Atlantic Ocean near the Caribbean Islands
Locally, the climate may differ from that dictated simply by latitude (position N or S of the equator) because of
- all of the above (mountain ranges that alter atmospheric flow patterns, cold and warm surface currents in the oceans, high elevations
Much carbon dioxide was removed from Earth’s original atmosphere by
- forming calcite (CaCO3) and other carbonate minerals in limestones
What is major source of water that falls as precipitation on the WESTERN US?
- the NW Pacific ocean
With regard to global atmospheric circulation, moist warm air ascends in the
- equatorial regions
Most of the world’s major deserts are located in the
- subtropical high-pressure belts
The source of energy the “fuels” motion in the ocean-atmosphere system is
- solar energy
The most imp. Layer of the atmosphere for geologic development of the surface is the
- troposphere bc that is where weather and the decay of rocks occurs
Which of the following gasses makes up the greatest % of the earth’s atmosphere?
- Nitrogen (N2)
The atmosphere is divided into several layers based on temp. gradients - in order upward they are
- troposphere, stratosphere, mesosphere, magnetosphere
The ocean has two important layers. Which is true of the upper layer as compared to the lower layer?
- the upper layer is well-mixed and turbulent
A geologist drills down into the continental crust and discovers this sequence of sedimentary rocks. Glacial tillite-stream sediments-sand dunes-coal and shale - assuming the changes were caused by the movement of the continent, which was the continent moving?
- toward a pole
The major dissolved constituent of the ocean is
- NaCl (Salt)
Which of the following minerals is most stable at earth’s surface?
- Quartz
During ___ weathering, the original minerals can be destroyed, and new minerals formed that are stable at earth’s surface
- Chemical
Joints aid in chemical weathering by
- increasing the surface area exposed to weathering agents
Which of the following common rock-forming minerals weathers to form most of the clay found in soils and regolith?
- Feldspar
The products of wedging often accumulate at the bases of cliffs to form piles of angular rock fragments called
- Talus
After granite has weathered and most of the igneous minerals have been altered to other minerals, which igneous mineral will probably NOT have been affected?
Quartz
The minerals hematite and limonite result from the chemical weathering of iron-rich minerals like olivine or pyrite by what process?
oxidation
Which of the following common rocks would be most susceptible to chemical weathering?
limestone
Chem. weathering would progress most rapidly in which location?
Northern South America
How is ice wedging important in preparing rocks for chemical weathering?
it enlarges fractures and cracks, therby inc. the surface area of the rock
the general term for the blanket of loose rock debris that covers large areas of Earth’s surface is
regolith
a talus accumulation consists largely of
coarse, angular rock fragments
which is NOT a type of physical weathering
a conversion of feldspar minerals to clay and soluble material (frost action, exfoliation/unloading, tree roots - all area phys. w)
ice wedging would be most effective in
areas where freezing and thawing occur many times a year
weathering is a near-surface phenomenon, but in somer egions chem. decpomosition may operate tens of meters below the surface if
the rocks are highly fractured
- Where would you expect to see solifluction?
Siberia
Which of the following factors decreases the risk of mass movement?
- adding vegetation to the side of a hill
The type of mass movement shown in the drawing is
mud flow
in this cross section of a valley, Slope A is
Stable - there are no planes of weakness sloping toward the highway
which of the following types of mass movement takes place most gradually?
creep
the immediate cause of incidents of mass movement is
graviation
the principal diff. btwn a lahar and a muflow is
former mass contains pyroclastic debris from a volcanic eruption
type of mass movement shown in pircture is (have it)
rockslide
in this cross section, slobe B is likely to be
unstable bc of bedding plane slippage
which of the following types of mass movement travels down a curved surface?
slump
which of the following dactors DECREASES risk of mass movement
adding vegetation to the side of a hill
which of the following INCREASES risk of mass movement
Flooding the sediment with water beyond saturation
what stripped the slope (in middle of photo) of trees and other vegetation?
a large landslide
- as the velocity of flow decreases…
ALL OF THE ABOVE
- –flow tends to become more laminar
- -the maximum flow velocity decreases
- -suspended sediment starts to be deposited
the lowest elevation to which a stream can down cut is the
base level
illustration of point bar
D
which creates this (picture) unique river pattern?
a braided stream has more sediment than it can carry