Differentiate the three types of magma based on igneous composition and silica content
What will be an ideal response?
Answer: Basaltic magmas have a mafic composition and approximately 50 percent silica. Andesitic magmas have an intermediate composition and 60 percent silica. Rhyolitic magmas have a felsic composition and contain more than 70 percent silica.
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Briefly contrast the general topography in the northern third of the map, with the topography in the southern two-thirds of the map. What might explain these differences?
The following questions are based on Map T-9, the “Park City, Kentucky” quadrangle (scale 1:24,000; contour interval 10 feet) and Figure 44-3, a stereogram of the same area (37°05'03"N, 86°05'27"W). The boundary of Mammoth Cave National Park is just beyond the northern margin of the map. The surface shown in the southern two-thirds of the map is predominantly limestone, whereas in much of the northern third, a layer of sandstone caps the limestone. What will be an ideal response?
Mass movement refers to the downslope movement of rock and soil under:
a. Pressure b. Friction c. Gravity d. None of the above
How is the decline in ocean fisheries considered an example of the "tragedy of the commons"?
What will be an ideal response?
The Ekman spiral is caused by ________
A) density differences in the water column B) the wind and gravity C) the wind and the Coriolis effect D) the pycnocline E) pressure gradients