Ch 12 Online Questions Physical Geo

The undulating form that gives Earth's surface its character and general configurations is called
Approximately what percentage of Earth's surface is exposed above sea level?
29 percent
The average elevation of the depth of the oceans is
-3,800 m (-12,470 ft)
An area that is a seismic gap
is overdue for an earthquake based on past earthquake frequency
The eventual catastrophic eruption of Mount Saint Helens was
related to seafloor subduction at the west coast of North America
Volcanic activity located away from plate boundaries is associated with
hot spots
Which of the following is NOT a result of extrusive volcanic activity?
Which of the following statements about shield volcanoes is correct?
The form from magic magma
Pulvarized rock and clastic materials ejected violently during an eruption are called
tephra, or pyroclastic
Explosive eruptions tend to build up
composite volcanoes
Volcanic activity generally doesn't occur
around the perimeter of the Atlantic ocean basin
A hypsographic curve
is a generalized curve showing Earth's surface by area and elevation in relation to sea level
The variety of surface features on Earth results from
gravity, tectonic activity, and weathering and erosion
Compared to oceanic crust, continental crust
is generally more complex in content and structure
The nucleus of old crystalline rock in each of the principal continental masses is called a
continental shield, or craton
Which of the following is correct regarding magma formed along a continental oceanic boundary?
The magma results in more violent volcanic eruptions than magma derived directly from the aesthenosphere. The magma has a higher silica content than magma formed from only oceanic crust. Batholiths may form from the rising magma.
High mountains consisting of tightly folded and overthrust sedimentary rock layers, as well as metamorphic rocks, are formed
during plate collisions
Domes can be formed by
up warping associated with magma movement (i.e. plutonic activity)
Which of the following can lead to the formation of mountains?
faulting, plate collisions and volcanic activity and exposure of plutons by erosion of surrounding landscape
Normal faults are associated with
tensional forces
When rock strata are strained beyond their ability to remain an intact unit, displacement occurs in a process known as
Molten rock that pours forth on Earth's surface is called
Volcanoes formed from silica-rich magma
are highly explosive and dangerous
A cindercone is formed from relatively______ viscosity magma with a ______ gas content.
Vertical elevation differences in a local landscape are referred to as