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Where have Cretaceous black shale deposits been found?
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Cretaceous Period
Distribution of landmasses, mountainous regions, shallow seas, and deep ocean basins during the late Cretaceous Period. Included in the paleogeographic reconstruction are the locations of the interval's subduction zones.
During the mid-Cretaceous, extensive deposition of carbon-rich black shales occurred globally due to severe oxygen deficiency in ocean bottom waters. These deposits are extensively distributed across various continental areas and oceanic regions.1
On land, Cretaceous black shales have been identified in the following locations:
* The western interior of North America1
* The Alps1
* The Apennines of Italy1
* Western South America1
* Western Australia1
* Western Africa1
* Southern Greenland1
Additionally, these deposits occur within the Atlantic Ocean, as confirmed by the Deep Sea Drilling Program, and in the Pacific Ocean, where they have been noted on several seamounts.1