GEOG 300 - Chapter 8

What type of plate boundary is associated with Iceland and its volcanic eruptions?

Divergent

Effusive eruptions are not related to which of the following?

Magma rich in silica and aluminum

The ________ scale would use Roman numerals to qualitatively describe an earthquake that causes "considerable-to-serious damage to buildings."

Modified Mercalli Intensity

Which of the following layers of Earth is liquid and is responsible for producing Earth's magnetic field?

Outer core

Which zone of Earth is in a liquid state?

Outer core

What causes hot spots?

Plate movement over a thermal plume

What type of rock is derived from the bits and pieces of former rocks?

Sedimentary

Which of the following is an example of an age-relationship based on relative dating?

The Coconino Sandstone of the Grand Canyon is younger than the Hermit Shale.

Which of the following is not an example of an age-relationship based on absolute dating?

The Coconino formation in the Grand Canyon is older than the Kaibab formation.

Which of the following is not used to rate an earthquake on the moment magnitude scale?

The amount of death and destruction that occurred

Orogenesis refers to

a general term for a mountain-building episode that thickens continental crust

The Hawaiian Islands were formed as a result of

a rising plume of magma from the mantle

Subduction occurs

along collision zones between continental and oceanic plates.

Intrusive igneous rocks cooled and hardened ________ the Earth's surface, resulting in ________ grained rocks than extrusive igneous rocks.

beneath; coarser

Explosive eruptions tend to build up

composite volcanoes

Mid-oceanic ridges occur at ________ plate boundaries.

divergent

The subsurface area where the motion of seismic waves is initiated along the fault plane is called the

focus, or hypocenter.

Continental crust is composed primarily of ________, while oceanic crust is composed primarily ________.

granite; basalt

________ applies to upward-faulted blocks that form mountains, whereas ________ applies to downward-faulted blocks that form valleys.

horst; graben

Knowledge of Earth's interior is mostly derived from

indirect evidence involving the analysis of surface features and seismic waves.

An effusive eruption ________, whereas an explosive eruption ________.

is an outpouring of low-viscosity magma onto the ground; is a violent eruption of magma, gas, and pyroclastics

The majority of the Earth's volume is within the

mantle

A rock transformed from any other rock through extreme heat and or pressure is referred to as

metamorphic

At which of the following locations is new ocean crust being formed?

mid-ocean ridges

Along ________ new ocean floor is formed by upwelling flows of magma, whereas along ________ old oceanic crust is destroyed.

mid-ocean ridges; subduction zones

Tensional stress along a fault can result in a downward shifting hanging wall block relative to the footwall side, producing a

normal fault

Compressional stress along a fault resulting in rocks moving upward along the fault plane is an example of a

reverse fault.

Volcanic mountains such as the Andes and the Cascade formed inland as a result of

rising plumes of magma associated with plate subduction on the west coasts of North and South America

Divergent plate boundaries are characteristic of

sea-floor spreading centers

The three basic rock types are

sedimentary, metamorphic, and igneous

A gently sloping mountain landform built from effusive eruption is known as a

shield volcano

The process whereby one portion of the lithosphere moves beneath another and dives downward into the mantle is called

subduction

In terms of dating of specific rocks, structures, or landscapes, absolute age refers to

the age of geological features based on radiometric dating techniques.

Ocean floor subducts under continents because

the ocean floor is more dense than continental material.

The oldest seafloor is a no more than 200 million years old because

the ocean floor subducts during plate collisions. To elaborate the ocean crust typically recycles back into the Earth's mantle at subduction zones (where two tectonic plates collide).

The principle that the same physical processes currently active in the environment were operating throughout Earth's history is known as

uniformitarianism

Which of the following gives the correct sequence of layers in Earth, from the surface to the center?

Crust, mantle, outer core, inner core

Be able to answer this question: What type of convergent boundary associated with orogeny is illustrated here? So be able to identify: Oceanic plate—continental plate collision

(Look at a diagram)

Be able to answer this question: What type of convergent boundary associated with orogeny is illustrated here? So be able to identify: continental plate-continental plate collision

(Look up diagram)

Be able to identify oceanic plate—oceanic plate collision

(look at a diagram)

While Earth is estimated to be 4.6 billion years old, the oldest oceanic crust is approximately ________ years old.

200 million

The thickness of Earth's crust ranges from

5 km to 60 km (3 mi. to 37 mi.)

Which type of volcanic cone is generally smallest and steepest?

Cinder cone

What type of orogenesis is responsible for the formation of the Himalayan Mountains?

Continental-continental plate collision

The fact that Earth's interior is sorted into layers indicates that

Earth was once in a molten state, during which materials became sorted based on density.

The heat from ________ is the energy that drives plate tectonics.

Earth's extremely hot interior

The area at the surface directly above the subsurface location where seismic waves are initiated is termed the

Epicenter

What is the point of origin of an earthquake inside Earth?

Focus

What is the significance of geomagnetism for plate tectonics?

Geomagnetism provided evidence of older rocks with distance from mid-oceanic ridges

Which of the following is correct regarding Alfred Wegener's hypothesis of continental drift?

He posited that 220 million years ago all the continents were joined together to form the supercontinent Pangaea

How do metamorphic rocks form?

Heat and intense pressure without melting bake the rock

Which statement describes Pangaea?

India was attached to Antarctica in Pangaea.

Which of the following was not offered as evidence to support Alfred Wegener's hypothesis of continental drift?

Lack of oceanic ridges that would indicate sea floor spreading