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Paleoclimate Īt a time of extreme global glaciation, the location of the Wellington deposit was equatorial and glacier-free. West of this valley, the Wellington shales gradually slope deeper underground beneath the Ninnescah Shale, but the unit extends no further West than the western Kansas border. South of Salina into northern Oklahoma, the westward dipping Wellington lies under a broad, shallow valley here, the upper Wellington has collapsed as the Hutchinson Salt member has dissolved, forming lowlands including the McPherson Valley Wetlands and the Wellington-McPherson Lowlands. The surface outcrop lies generally along or between the north–south highways U.S. The Wellington is identified in western Kansas, northwest Oklahoma, and the northeast corner of the Texas Panhandle, but with no identification in Nebraska (compare with relative extension of the underlying Chase Group into Nebraska and Eastern Kansas). Marine fossils are limited to the lowest beds while the remainder features freshwater species and land life, particularly insects and reptiles.Ĭompared to the earlier Permian rock formations in the midcontinent, the Wellington is somewhat more restricted in range. Localized red beds and green shales indicate conditions of exposed soils with shallow freshwater tables. There are several variable beds of anhydrite and gypsum and the central body of most of the formation is a massive salt bed. Initially described as marine shales, the 500–700 feet (150–210 m) thick Wellington appears mostly as dark gray, thinly bedded soft rock, much of it terrestrial, with sediments from fresh water ponds and salt lakes. Tens of thousands of insect fossil recovered from the Wellington shales are kept in major collections at the Harvard Museum of Comparative Zoology and Yale Peabody Museum of Natural History. The Wellington provides a rich record of Permian insects and its beddings provide evidence for reconstruction of tropical paleoclimates of the Icehouse Permian with the ability in cases to measure the passage of seasons. The formation's Hutchinson Salt Member is more recognized by the community than the formation itself, and the salt is still mined in central Kansas. The Wellington Formation is an Early Permian geologic formation in Kansas and Oklahoma. Wellington Formation (Kansas) Show map of Kansas