Geology the science that pursues an understanding of planet Earth
Physical geography examines the materials composing Earth and seeks to understand the
many processes that operate beneath and upon its surface
Historical geology to understand the
Viscosity a measure of a fluids resistance to flow.
Volatiles gaseous components of magma dissolved in the melt; volatiles will readily vaporize
(form a gas) at surface pressures.
Eruption columns buoyant plumes of hot, ash-laden gases that can extend tho
Igneous rock rock formed from the crystallization of magma
Magma a body of molten rock found at depth, including any dissolved gases and crystals
Lava magma that reaches Earths surface
Melt the liquid portion of magma excluding the solid crystals
Through igneous and metamorphic rocks make up most of the crust by volume, sediment and
sedimentary rocks are concentrated near the surface. There, at the interface between Earths four
spheres, sediments and the rock layers that eventually form make a re
1. In Figure 7.5, the strike of the rock layer in map view A (left) is north _
a. 60 west
b. 30 west
c. 60 east
d. 30 east
2. In Figure 7.5, the direction of the dip of the rock layer in map view A (left) is _ and the angle
of dip is _
a. Northwest / 30
Weathering the disintegration and decomposition of rock at or near the surface of Earth
Mechanical weathering the physical disintegration of rock, resulting in smaller fragments
Chemical weathering the processes by which the internal structure of a minera
From the land surface downward to the unweathered bedrock, which of the following is the correct order
of the different soil horizons? O, A, E, B, C, bedrock.
What two factors speed up rates of chemical reaction and weathering in rocks and soils
Flint, chert, and jasper are microcrystalline forms of quartz.
Detrital sedimentary rocks are classified mainly on the basis of grain sizes of the detrital particles.
Which of the following features of sedimentary rocks IS NOT a sedimentary stru
Mount St. Helens is an explosive stratovolcano.
Which of the following shows the correct order (left to right) of decreasing magma viscosity? Rhyolite,
Which of the following are usually the most abundant gases emitted during b
Which of the following igneous rocks has a pyroclastic texture? Rhyolitic tuff.
The sizes, shapes, and arrangements of mineral grains in an igneous rock is known as texture.
Changing the composition of magma by incorporating surrounding host roc