
The Earth's Mantle
The great shell of sllicate that lies above the metallic core is heated by the decay of radiQactive isotopes. The heat energizes massive convection currents in the upper 700 kllometers of the ductile rock

The Earth's Mantle
The great shell of sllicate that lies above the metallic core is heated by the decay of radiQactive isotopes. The heat energizes massive convection currents in the upper 700 kllometers of the ductile rock

Convection Currents in the Earth's Mantle
The steady motion of the plates that form the earth's crust is evidence for convection currents on a vast scale. Laboratory studies indicate that there should be smaller currents as well

The Evolution of the Indian Ocean
A 75-million-year magnetic record in the floor of the Indian Ocean reveals how India was rafted northward for 5,000 kilometers before it collided with Asia. The encounter gave rise to the Himalayas