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East Antarctica is geologically very old, dating from the Precambrian, with some rocks formed more than 3 billion years ago. It is composed of a metamorphic and igneous platform which is the basis of the continental shield .
The history of Antarctica emerges from early Western theories of a vast continent, known as Terra Australis, believed to exist in the far south of the globe. The term Antarctic , referring to the opposite of the Arctic Circle , was coined by Marinus of Tyre in the 2nd century AD.
Gondwana (/ ɡ ɒ n d ˈ w ɑː n ə /) [1] was a large landmass, sometimes referred to as a supercontinent.The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia, Zealandia, Arabia, and the Indian Subcontinent.
Antarctica is the remotest part of the world, but it is a hub of scientific discovery, international diplomacy and environmental change. It was officially discovered 200 years ago, on Jan. 27 ...
Breakup of the super-continent Gondwana started in the early Jurassic around 184 million years ago (Ma), but Antarctica did not break up from Australia until the late Cretaceous (80 Ma). Just before the breakaway in the Late Jurassic and Early Cretaceous, rifting began to occur near the soon-to-be Transantarctic Mountains. [1]
A giant impact crater beneath the Wilkes Land ice sheet was first proposed by Richard A. Schmidt in 1962 on the basis of the seismic and gravity discovery of the feature made by the U.S. Victoria Land Traverse in 1959–60 (VLT), and the data provided to Schmidt by John G. Weihaupt, geophysicist of the VLT (Geophysical Studies in Victoria Land, Antarctica, Report No. 1, Geophysical and Polar ...
The end of the last glacial period, which was about 10,000 years ago, is often called the end of the ice age, although extensive year-round ice persists in Antarctica and Greenland. Over the past few million years, the glacial-interglacial cycles have been "paced" by periodic variations in the Earth's orbit via Milankovitch cycles.
δ 18 O, a proxy for temperature, for the last 600,000 years (an average from several deep sea sediment carbonate samples) [a]. The 100,000-year problem (also 100 ky problem or 100 ka problem) of the Milankovitch theory of orbital forcing refers to a discrepancy between the reconstructed geologic temperature record and the reconstructed amount of incoming solar radiation, or insolation over ...