Quaternary dating wiki

The name was intended to cover the recent period of repeated glaciations; however, the start was set too late and some early cooling and glaciation are now reckoned to be in the Gelasian (end of the Pliocene).Some climatologists and geologists would therefore prefer a start date of around 2.58 million years BP.

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North central North America was totally covered by Lake Agassiz.

Over 100 basins, now dry or nearly so, were overflowing in the American west.

The Andes were covered in the south by the Patagonian ice cap. The current decaying glaciers of Mount Kenya, Mount Kilimanjaro, and the Ruwenzori Range in east and central Africa were larger.

Glaciers existed in the mountains of Ethiopia and to the west in the Atlas mountains.

The proposal of INQUA is to extend the beginning of the Pleistocene to the beginning of the Gelasian Stage, shortening the Pliocene, and ending the Neogene with the revised end of the Pliocene.

The modern continents were essentially at their present positions during the Pleistocene, probably having moved no more than 100 km since.

Each glacial advance tied up huge volumes of water in continental ice sheets 1500-3000 m thick, resulting in temporary sea level drops of 100 m or more over the entire surface of the Earth.

During interglacial times, such as at present, drowned coastlines were common, mitigated by isostatic or other emergent motion of some regions. Antarctica was ice-bound throughout the Pleistocene as well as the preceding Pliocene.

The end of the Younger Dryas has been dated to about 9600 BC (11550 calendar years BP).

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