A geologist is working in an area of old volcanic rocks exposed by erosion. He finds a large rock outcrop that contains flat lying gravels in the base of the outcrop
These gravels are overlain by basalt that forms a series of layers representing flows. The uppermost basalt lava flows have a dip of about 10 degrees to the west. What does this outcrop record?
A) Gravels were initially deposited in a river valley and a cinder cone was erupted, damming the valley, before a cinder cone formed.
B) Basalt flows formed after gravels were deposited, covered the local terrain, and built a shield volcano with dips of about 10 degrees.
C) Basalt flows formed above a series of gravels, filling a river valley.
D) You can't tell anything about the history of this region from this outcrop.
B
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Cyclone
?
The following questions refer to the above illustration of a middle-latitude cyclone. The dashed lines show the positions of the fronts six hours ago.
Which of the following descriptions is associated with an omega high?
A. It does not stay in the same geographic area for long. B. It produces high surface wind speeds. C. It forms when the flow aloft is meridional. D. It is known as a shallow high.
Compare and contrast the effectiveness of Statutory Law (the Legislative Branch), Case Law (The Judicial Branch), and Administrative Law (The Executive Branch) in determining environmental policy.
What will be an ideal response?
The three models describing the internal social structure of cities were developed in this city:
A) Sacramento B) New York City C) Seattle D) Chicago E) Boston
Explain the ways in which alluvial fans and deltas are similar. What will be an ideal response?