EARTHQUAKES-Churning Earth

ambience: Earthquake sounds

We’re listening to speeded up recordings of a South American earthquake.

The mantle is the layer inside the earth between the crust and the core. Scientists have known that the churning of the mantle is what causes the crust to break up and fracture into earthquakes. But recently geologists have started using seismic waves, generated by earthquakes, to create images of the movement taking place inside the mantle.

Mike Brown is the chair of the geophysics program at the University of Washington in Seattle.

“The Earth is a very dynamic planet. It is releasing heat generated and trapped within the interior, much like a boiling pot of soup on a stove. You see rising sections and sinking portions. “

The mantle moves like a giant blob of silly putty, rising towards the crust a few centimeters a year, bringing the earth’s inner heat with it.

“The rock at the earth’s surface begins to sink again. Falling back through the mantle to the greater depths where it again can pick up the internal heat and be recirculated up to the Earth’s surface and whereas the pot of soup on the stove will overturn in a mere seconds, the Earth requires say a hundred million years or more to complete a cycle of material going from the Earth’s surface down to great depth and perhaps similar time scale to come back up again.”

Pulse of the Planet is presented by DuPont, bringing you the miracles of science, with additional support by the National Science Foundation.

EARTHQUAKES-Churning Earth

Recently geologists have started using seismic waves, generated by earthquakes, to create images of the movement taking place deep inside the earth.
Air Date:02/16/2000
Scientist:
Transcript:

ambience: Earthquake sounds

We're listening to speeded up recordings of a South American earthquake.

The mantle is the layer inside the earth between the crust and the core. Scientists have known that the churning of the mantle is what causes the crust to break up and fracture into earthquakes. But recently geologists have started using seismic waves, generated by earthquakes, to create images of the movement taking place inside the mantle.

Mike Brown is the chair of the geophysics program at the University of Washington in Seattle.

"The Earth is a very dynamic planet. It is releasing heat generated and trapped within the interior, much like a boiling pot of soup on a stove. You see rising sections and sinking portions. "

The mantle moves like a giant blob of silly putty, rising towards the crust a few centimeters a year, bringing the earth's inner heat with it.

"The rock at the earth's surface begins to sink again. Falling back through the mantle to the greater depths where it again can pick up the internal heat and be recirculated up to the Earth's surface and whereas the pot of soup on the stove will overturn in a mere seconds, the Earth requires say a hundred million years or more to complete a cycle of material going from the Earth's surface down to great depth and perhaps similar time scale to come back up again."

Pulse of the Planet is presented by DuPont, bringing you the miracles of science, with additional support by the National Science Foundation.