the quaternary system
41Gélasien — ère Cénozoïque Néogène Holocène Pléistocène Pliocène • Gélasien • Plaisancien …
42Chad Basin — The Chad Basin, also known as the Lake Chad Basin, is a large lowland area in north central Africa. In all directions from the center of this area the elevation changes are gentle. The Chad Basin is an endorheic (closed) basin its water does not… …
43100,000-year problem — The 100,000 year problem is a discrepancy between past temperatures and the amount of incoming solar radiation, or insolation, which grows and shrinks periodically on a 100,000 year (100 ka) timescale.Due to variations in the Earth s orbit, the… …
44Choline — The N,N,N trimethylethanolammonium cation, with an undefined counteranion, X− Choline is a water soluble essential nutrient.[1][ …
45Pre-Illinoian — The Pre Illinoian Stage is often synonymous with Pre Illinoian glacial[1][2] and used by Quaternary geologists for the early and middle Pleistocene glacial and interglacial periods of geologic time in North America from 2.5 Ma 500,000 years ago,… …
46Kobuk River — The Kobuk River is approximately convert|280|mi|km|0|lk=on long, located in the Arctic region of northwestern Alaska in the United States. [USGS Geographic Names Information System (GNIS). [http://geonames.usgs.gov/pls/gnispublic/f?p=gnispq:3:::NO… …
47Glacial history of Minnesota — The glacial history of Minnesota is most defined since the onset of the last glacial period, which ended some 10,000 years ago. Within the last million years, most of the Midwestern United States and much of Canada were covered at one time or… …
48North American Cordillera — The North American Cordillera is the North American portion of the American Cordillera which is a cordillera extending up and down the western side of the Americas. The North American Cordillera covers an extensive area of mountain ranges,… …
49Potrillo volcanic field — The Potrillo Volcanic Field is a monogenetic volcanic field located on the Rio Grande Rift in New Mexico, USA and Chihuahua, Mexico. It lies convert|35|km|mi|0 west of El Paso, Texas. Rio Grande Rift *Rifting began in Late Oligocene cite book |… …
50Mastogloia Sea — The Mastogloia Sea is one of the prehistoric stages of the Baltic Sea in its development after the last ice age. This took place ca. 8000 years ago following the Ancylus Lake stage and preceding the Littorina Sea stage. Note: The dates used in… …
