Science Chapter 7 Section 1

The mantle has less of these two elements than the crust?

aluminum and silicone

Why are tectonic plates like the pieces of a jigsaw puzzle?

because not all tectonic plates are the same. Tectonic plates fit with the tectonic plates that surround it.

mesophere

beneath the asthenosphere is the strong, lower part of the mantle called the mesosphere. The mesospher extends from the bottom of the asthenosphere to the Earth's core.

List three ways in which tectonic plates floating on the asthenosphere are similar to ice cubes filling a punch bowl.

cover the surface, touch one another and move around.

What element makes up most of the Earth's core?

iron

Oceanic crust is denser than the continental crust because it contains more of which three elements?

iron, calcium, and magnesium

tectonic plates

large pieces of the lithosphere that move around on the asthenosphere.

The Earth is composed of several what?

layers

Why do less dense compounds make up Earth's crust while the densest compounds make up the core?

less dense compounds make up the earth's crust because heavier elements are pulled toward the earth by gravity.

The mantle is composed more of this element than the crust?

magnesium

What are two kinds of crust that a tectonic plate may contain?

oceanic crust and continental crust

How much of the Earth's mass is made up by the core?

one third

What three elements make up most of the Earth's crust?

oxygen, silicon, and aluminum

Why do scientists look to the ocean floor to research the mantle?

scientists look at the ocean floor because magma from the mantle flows out of active volcanoes on to the ocean floor and the underwater volcanoes give scientists many clues as to the composition of the mantle.

What do scientists use to study Earth's interior?

seismic waves

outer core

the Earth's core is divided into two parts-the outer core and the inner core. The outer core is the liquid layer of the Earth's core that lies beneath the mantle and surrounds the inner core.

inner core

the inner core is the solid, dense center of our planet that extends from the bottom of the outer core to the center of the Earth, which is about 6,380 km beneath the surface.

List the three layers of the Earth, based on their composition?

the three layers of the earth are the crust, mantle, and core.

What are seismic waves?

vibrations from an earthquake

Will a seismic wave traveling through a solid go faster or slower than a seismic wave traveling through a liquid ? Why or why not?

a seismic wave going through a solid will go faster than a seismic wave going through a liquid because typically a solid is much more dense than a liquid.

compound

a substances composed of two or more elements is a