Geography 1 - Chapter 8 H/W

Which of the following is true regarding the geologic time scale?

Both relative and absolute dating methods are used in determining the sequence of the time scale.

Alfred Wegner's theory of continental drift was immediately accepted by the scientific community when it was proposed.

False

Silt and clay are likely to be deposited in a beach environment.

False

Which of the following is false relative to hot spots?

Hot spot activity is unrelated to the formation of Iceland, which sits atop a sea-floor spreading ridge in the North Atlantic.

The boundary between the crust and the rest of the lithospheric upper mantle is a discontinuity known as the

Moho.

Which of the following statements about Earth's core is false?

The inner core is believed to be liquid and the outer core solid.

The crust is thickest under mountains and thinnest under the oceans.

True

The geologic cycle is powered both by exogenic and endogenic energy systems.

True

Plate boundaries are associated with

all of these

The shape of Earth's surface results from

all of these

At which of the following locations does subduction occur?

along collision zones between continental and oceanic plates

The Sierra Nevada mountain range in California is an example of

an exposed batholith.

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

crust, asthenosphere, lower mantle, core

Continental crust is basically ________, whereas oceanic crust is basically ________.

granite; basalt

Earth's interior is

heated unevenly by the heat of radioactive decay.

The majority of Earth's crust is composed of ________ rock.

igneous

Knowledge of Earth's interior is derived from

indirect evidence involving the analysis of seismic waves.

A batholith forms from

intrusive igneous rock.

Earth's North Magnetic Pole

is moving at a rate of 55-60 km per year.

Earth's magnetic field

is variable, and it has phased to zero some nine times during the past 4 million years.

Which layer of the planet forms 80 percent of Earth's total volume, and has an average density of 4.5 grams per cm2?

mantle

A rock transformed from any other rock through profound physical and/or chemical processes is referred to as

metamorphic

An element or combination of elements that forms an inorganic, natural compound is called a

mineral.

The idea that Earth formed only a few thousand years ago is

not based upon physical evidence and is more appropriately considered a belief.

The asthenosphere can best be described as

plastic-like.

Which of the following is an example of an intrusive, igneous rock?

pluton

Which of the following is the fuel for continental drift and plate tectonics?

radioactive decay

Several large, linear lakes are forming in East Africa. This is evidence of what process?

rifting

Three types of rock-forming processes compose the

rock cycle.

With increasing depth, the mantle becomes ________ due to greater ________.

stiffer; pressures

When geologists or archaeologists dig downward into a unit of rock or sediment, they are digging "back in time." This fact is based on the principle of ________.

superposition

Heat energy and new materials are brought to the surface from the interior by the

tectonic cycle.

Which of the following is endogenic in nature?

volcanism

Which of the following are located along the midocean ridges?

volcanoes

Tectonic forces

warp, fold, and uplift rock.

Which of the following is exogenic in nature?

weathering

The sea-floor spreading center that led to the formation of the Atlantic Ocean accelerated dramatically between

135 and 65 million years ago.

Which of the following is correctly matched?

4: upper mantle

The thickness of Earth's crust ranges from

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

What percent of Earth's crust is composed of only eight natural elements?

99