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Palomas Formation
The Palomas Formation is a Formation (geology), geologic formation exposed in the southern Rio Grande rift of New Mexico. It preserves fossils dating back to the Pliocene to Quaternary. Description The formation is composed of beds of poorly Cementation (geology), cemented Conglomerate (geology), conglomerate, sandstone, and siltstone, with a total thickness of . The formation is better cemented to the west, where it resembles the Gila Formation. The conglomerate is gray to brown, poorly to moderately sorted, and contains clasts of tuff, basalt, rhyolite, and andesite up to long. The siltstone is well-Sorting (geology), sorted and trough-crossbedded. The formation may Correlation (geology), correlate with the Sierra Ladrones Formation to the north and the Camp Rice Formation to the south. The age is estimated as 5 million years (Ma (unit), Ma) to 0.4 Ma. The formation includes both piedmont and axial river facies. The piedmont facies represents alluvial fans and other sedimen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formation (stratigraphy)
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics (lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by Abraham Gottlob We ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
