Earth Science Chapter 4 Review

What provides the matter and energy for plate movement?

uses sound waves to calculate distance

measures the strength of the magnetic field

The name ___ means "all land".

Wegener's supercontinent was named ___.

continents move slowly across Earth's surface

The mid-ocean ridge is important in understanding plate tectonics primarily because

GPS is used to study plate ___.

The second force behind plate movement is ___, which occurs at mid-ocean ridges.

If a scientist recorded the epicenters of earthquakes over years, she would probably find that

the force of gravity moves the plate down and away from the ridge

The theory that describes Earth's crust as being broken into sections is called ___.

The three forces that factor into the movement of lithospheric plates are:

Earth's ___ move around on the upper layer of the mantle.

Diamonds are used in some drill bits because they ___.

Which action occurs at the mid-ocean ridge?

If new seafloor is created at the mid-ocean ridge, rock there should be the ___on the seafloor.

Drilling discovered that the ___ rocks were in the center of the mid-ocean ridge.

What causes seafloor spreading?

___, occuring in the upper mantle, are thought to be the force behind plate tectonics.

a plate is forced into a mantle

What term describes the cycle of heating, rising, cooling, and sinking?

This diagram shows ______.

What provided scientists with evidence of magnetic polarity reversals?

What can occur when plates slide past one another?

Who proposed the seafloor spreading theory?

Slab pull is caused by plates moving away from the ridges and ___.

Which would best describe the speed of plate movement?

Alfred Wegener started thinking about continental drift when he noticed ___.

The rigid part of the plate of the ___ are made of oceanic or continental crust.

uses pulses of light to measure distance

network of satellites used to determine locations on Earth

___ hypothesized that continents are in motion through continental drift.

How do scientists describe the orientation of the magnetic field today?

Evidence of the location of plate boundaries includes

Which best describes plate boundaries?

If new crust is always being added at mid-ocean ridges, why doesn't our crust keep expanding?

What forms the mid-ocean ridges?

Are fish fossils good evidence of continental drift?

Where are the youngest rocks in the ocean floor located?

How do ocean floor rocks compare with continental rocks?

The first force behind plate movement is ___, which is caused by heat and differences in ___.

The Glomar Challenger helped scientists support the theory of seafloor spreading by

GPS measure the speed and direction of tectonic plates by ___.

GPS and SLR both use satellites to study Earth; GPS uses radio signals, and SLR uses

The ___ was a boat designed to drill and collect samples from the seafloor.

___ studied the seafloor to see how the mid-ocean ridge was formed.

When scientists studied the mineral grains in seafloor rocks, what did they find had reversed?

Hess theorized that new seafloor is created at the ___.

Why have glacial deposits been found in Africa?