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Such evidence suggests major periods of glaciation prior to the current Quaternary glaciation. One of the best documented records of pre-Quaternary glaciation, called the Karoo Ice Age, is found in the late Paleozoic rocks in South Africa, India, South America, Antarctica, and Australia. Exposures of ancient glacial deposits are numerous in ...
A minor series of glaciations occurred from 460 to 430 Ma, and there were extensive glaciations from 350 to 289 Ma. The Late Cenozoic Ice Age has seen extensive ice sheets in Antarctica for the last 34 Ma. During the last 3 Ma, ice sheets have also developed on the northern hemisphere.
The list of periods and events in climate history includes some notable climate events known to paleoclimatology. Knowledge of precise climatic events decreases as ...
Violet: Extent of the Alpine ice sheet in the Würm glaciation.Blue: Extent in earlier ice ages. The Late Pleistocene is an unofficial age in the international geologic timescale in chronostratigraphy, also known as the Upper Pleistocene from a stratigraphic perspective.
The Laurentide ice sheet (LIS) was a massive sheet of ice that covered millions of square miles, including most of Canada and a large portion of the Northern United States, multiple times during the Quaternary glaciation epochs, from 2.58 million years ago to the present.
The Quaternary is characterized by alternating glacial periods, during which extensive ice sheets cover large portions of the Earth, and interglacial periods, which are warmer with reduced ice cover. The oscillation between glacial and interglacial periods is due to the Milankovitch cycles. These are cycles that have to do with Earth's axial ...
However, the Nebraskan Stage, along with the Kansan and Aftonian Stages, have been abandoned by North American Quaternary geologists and merged into the Pre-Illinoian Stage. [ 7 ] [ 8 ] As of 2011 [update] , the Beestonian stage is correlated with the period of time that includes the Pre-Illinoian F, Pre-Illinoian G, and Pre-Illinoian H ...
For example, instead of two glaciations having occurred prior to the Illinoian Stage, researchers found that 11 distinct glaciations had occurred. In addition, what was presumed to have been a single volcanic ash bed, which was used to correlate and differentiate between Kansan and Nebraskan glacial deposits, was found to be three volcanic ash ...