Because the field has reversed directions at irregular intervals throughout its history, the pattern of geomagnetic reversals in the ocean crust can be used as an indicator of age.
22.
The magnetic data he collected from the ocean crust later was interpreted as containing field reversals that were used by Canadian geophysicist Lawrence Morley to prove seafloor spreading and plate tectonics.
23.
"' Sir Edward " Teddy " Crisp Bullard "'geothermal heat flow through the ocean crust, and was one of the first to find new evidence for the theory of continental drift.
24.
This was the first time such a feat had been accomplished in intact ocean crust and was ranked by Discover Magazine as one of the top eight Earth Science stories of 2006.
25.
It turned out, however, that the abyss is alive with volcanic fissures that form the ocean crust, circulate huge masses of sea water and feed unusual forms of life adapted to volcanic heat and chemistry.
26.
The dominant school holds that early volcanic isles and micro-continents ( like Iceland or Japan ) could have traveled along this tectonic conveyor belt and been sandwiched together as the ocean crust plunged downward in subduction zones.
27.
It is the eroded remnants of a mountain range formed 1.2 billion years ago . " The park provides a rare example of the process of continental drift, where deep ocean crust and the rocks of the earth's mantle lie exposed ."
28.
During the early stages of this mountain building known as the Taconic orogeny, a piece of ocean crust from the Iapetus ocean broke off and became incorporated into the collision zone and now forms the oldest bedrock strata of Staten Island, the serpentinite.
29.
During the last half of the Mesozoic Era, the Age of the Dinosaurs, much of today's California, Oregon, and Washington were added to North America . western North America suffered the effects of repeated collision as slabs of ocean crust sank beneath the continental edge.
30.
To the west of the Levantine Deep Marine Basin is the Nile Delta Basin, followed by the Herodotus Basin, 130, 000 km?large and up to 3, 200 meters deep, which-at a possible age of 340 million years-is believed to be the oldest known ocean crust worldwide.
