Ch 11

Pangaea is currently dated at

225 million years ago

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

The bulk of Earth's history has occurred during the Precambrian eon

The Hawai'ian Islands were formed as a result of

a rising plume of magma from the mantle.

Felsic igneous rocks, such as granite and rhyolite,

are high in silicate minerals

Earth's magnetic poles

are migrating approximately 60 km (37 mi.) per year

The plastic layer in the mantle from about 70 to 250 km (43 to 155 mi.) in depth is known as the

asthenosphere.

Which of the following lists, in proper sequential order, the steps leading to the formation of clastic sedimentary rock?

erosion, transportation, deposition, lithification

he subfield of geography and geology concerned with the study of the origins, evolutions, form, and spatial distribution of the Earth's landforms is

geomorphology

What type of rock forms from the solidification of molten material?

igneous

The temperature of Earth's interior

increases with depth so the hottest temperatures are found within Earth's core.

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

The three most abundant elements in Earth's crust are

oxygen, silicon, and aluminum

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

pluton

Approximately 95% of the Earth's crust is made up of

silicates

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

the age of geological features based on radiometric dating techniques

The occurrence of contact metamorphism would be direct evidence for

the local intrusion of magma

Ocean floor subducts under continents because

the ocean floor is made of mafic material and is therefore more dense than continental material

Areas where plates slide past one another, usually at right angles to a seafloor spreading, are

transform boundaries

The age of the sea floor increases with increasing distance from a mid-ocean ridge.

true

Which of the following is an endogenic process?

volcanism

Which of the following are located along the mid-ocean ridges?

volcanoes

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.

Which of the following provided support for plate tectonic theory?

Earthquakes and volcanoes are concentrated in narrow linear bands rather than randomly distributed across the planet.

Limestone formed from the shells of marine organisms is an example of ________ sedimentary rock.

biochemical