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13-463: Fossils of the gomphothere Haplomastodon waringi , the capibara Neochoerus sp. and the deer species Odocoileus cf. salinae have been found in the Soatá Formation. Knowledge about the formation has been provided by Colombian geologists Carlos Villarroel, Jorge Brieva and others. The formation was first proposed and named after Soatá by Villarroel et al. in 2001. The type locality

26-594: A reclassification of the South American gomphotheres as follows: Other researchers as Labarca, Prado and Alberdi agree with the placement of species into Notiomastodon , but reject the idea of a single species. They continue to use Stegomastodon waringi for South American gomphotheres from Chile. Publications are in chronological order, most recent first, because of the advances in taxonomy and research Depositional environment In geology , depositional environment or sedimentary environment describes

39-422: Is composed of basal greyish claystones with non-uniform matrix-supported conglomerates at the upper section. The uppermost layer contains siltstones, probably of volcaniclastic origin. The youngest sediments are found deepest in the basin and consist of claystones and greenish matrix-supported conglomerates. Rootlets and mammal fossils are more abundant in this layer. The Soatá Formation unconformably overlies

52-714: Is defined near Portugalete, Soatá. The Altiplano Cundiboyacense, in the Eastern Ranges of the Colombian Andes, was formed late in the regional uplift of the Andean orogeny . It is estimated that the main stage of uplift happened during the Plio - Pleistocene . The Western and Central Ranges were submerged much earlier, leaving a corridor to the Caribbean in the Neogene . The compression in

65-571: Is fragmentary. The Soatá Formation is apart from its type locality Portugalete found around Soatá (Jútua), and stretches to the north near the border of Boyacá and Santander , northeast of Tipacoque . To the south, the formation may have reached until Socotá . List of gomphothere fossils in South America This is a list of gomphothere fossils found in South America . Gomphotheres were elephant-like mammals that lived from

78-753: The Cretaceous Capacho Formation , and is overlain by the Holocene infill sediments of the Chicamocha River , the course of which severely eroded and fragmented the Soatá formation. The formation is subdivided into three units of different lithological character and sedimentary dip in a terrace setting. The Soatá Formation is time-equivalent with the upper part of the Sabana Formation on the Bogotá savanna and

91-540: The Middle Miocene (approximately 12 million years ago) to the Holocene (6000 years BP ). The following species have been described in twentieth and twenty-first century paleontological literature about South America. An alternative proposal is considered within the scientific community, listed below . Modern classification Original classification Formations are ordered according to their youngest age Some authors, Lucas , Mothé, Avilla et al., propose

104-938: The glacials and interglacials of the Pleistocene ("ice ages"), several paleolakes formed on the Altiplano Cundiboyacense, of which Lake Humboldt on the Bogotá savanna was the most extensive (approximately 4,500 square kilometres (1,700 sq mi)). Rivers were restricted during the drier glacial periods and the vegetation changed from páramo to Andean forest between the glacials and stadials and interglacials and interstadials. The Soatá Formation consists of whitish calcareous claystones and sandy siltstones with plagioclase , hematite , zircon , green and reddish biotite , hornblende and crystalline calcite in its upper, older terrace. This unit also contains foraminifera and fragments of shells. The middle, younger unit

117-630: The Andean orogenic belt caused the formation of fold and thrust belts in the Eastern Ranges, where Cretaceous and Jurassic normal faults were inverted as thrust faults lifting up the Paleozoic ( Floresta and Cuche Formations ), Mesozoic and Paleogene strata. A hiatus existed on the Altiplano between the Late Eocene and Late Miocene , in several parts of the Altiplano continuing until the Pleistocene. During

130-584: The Chinauta deposits near Fusagasugá in the southwest of the Altiplano. Two samples were analysed for radiometric dating and provided ages of 45,900 ± 1,600 and 39,600 ± 800 years BP . This corresponds to the Chicagota interstadial and the Tagua stadial , when the glaciations were at their maximum extent. The depositional environment has been interpreted as lacustrine ( Lake Soatá ) and fluvio-deltaic. Contrasting with

143-403: The combination of physical, chemical, and biological processes associated with the deposition of a particular type of sediment and, therefore, the rock types that will be formed after lithification , if the sediment is preserved in the rock record. In most cases, the environments associated with particular rock types or associations of rock types can be matched to existing analogues. However,

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156-446: The further back in geological time sediments were deposited, the more likely that direct modern analogues are not available (e.g. banded iron formations ). Continental Transitional Marine Others Depositional environments in ancient sediments are recognised using a combination of sedimentary facies , facies associations , sedimentary structures and fossils , particularly trace fossil assemblages, as they indicate

169-411: The wide and shallow Lake Humboldt on the Bogotá savanna , Lake Soatá was probably close to 400 metres (1,300 ft) deep. The paleolake was approximately 30 kilometres (19 mi) long and widest between Soatá and Boavita at 7 kilometres (4.3 mi). In the Soatá Formation, fossils of Haplomastodon waringi , Neochoerus sp. and Odocoileus cf. salinae have been found. The fossil content

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