Coquimbo Formation Stratigraphic range: Miocene–Mid Pleistocene ~23–1.2 Ma | |
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Marine terrace exposing strata of the Coquimbo Formation, at Caleta Hornos | |
Type | Geological formation |
Underlies | Alluvium |
Overlies | Liman Formation |
Thickness | 63 m (207 ft) |
Lithology | |
Primary | Conglomerate, sandstone, siltstone, shale and coquina |
Other | Clay lenses, terra rossa |
Location | |
Coordinates | [ ⚑ ] : 30°20′21″S 71°32′03″W / 30.33917°S 71.53417°W |
Paleocoordinates | [ ⚑ ] 30°06′S 70°18′W / 30.1°S 70.3°W |
Region | Coquimbo Region |
Country | Chile |
Extent | Tongoy Bay |
Type section | |
Named for | Coquimbo |
Coquimbo Formation (Spanish: Formación Coquimbo) is a Miocene to Middle Pleistocene sedimentary formation located in Coquimbo Region in Norte Chico, Chile . The lowermost unit belongs to the lower Miocene, with the third-deepest unit dated at 11.9 ± 1.0 Ma. The uppermost unit of the formation is estimated at 1.2 Ma. In the area of Tongoy, the Coquimbo Formation was deposited in an ancient bay that was formed in a graben or half-graben, with a normal fault dipping east. Sea level changes during the Holocene have caused erosion to cut several marine terraces into the formation.[1]
The following fossils have been found in the formation:
SALMA | Group | Fossils | Notes |
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Montehermosan | Mammals | Delphinus domeykoi, Megaptera hubachi, Pliopontos sp., ?Squalodon sp., Balaenidae indet. | |
Birds | cf. Palaeospheniscus sp., Spheniscus sp., Diomedeidae indet., Spheniscidae indet. | ||
Fish | Carcharodon carcharias | ||
Mayoan | Cosmopolitodus hastalis |
Original source: https://en.wikipedia.org/wiki/Coquimbo Formation.
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