Depositional Environment of Coral–Rudist Associations inthe Upper Cretaceous Cardenas Formation (Central Mexico)

Geologia Croatica

Rosemarie A. Baron-Szabo¹  Wolfgang A. Stinnesbeck²  Stefan A. Goetz³  Armin A. Schafhauser³ 

[1] Department of Invertebrate Zoology, Smithsonian Institution;Geological Institute, University of Karlsruhe (TH);Geological Institute, University of Karlsruhe;

关键词: Upper Cretaceous, Maastrichtian, Reefs, Corals, Rudists;   

DOI  :  10.4154/GC.2003.12

来源: DOAJ

【 摘 要 】

In the Cardenas Formation (central Mexico), a 175 m thick sedimentary

sequence of Maastrichtian age was analyzed with respect to its palaeontology and sedimentology. A wide variety of lithological and palaeontological features characterize this sequence comprising unfossiliferous and fossil-bearing sand- and siltstones, and diverse rudist and coral–rudist associations in carbonate or mixed carbonate/clastic lithologies. A total of 24 rudist and coral–rudist associations are exposed in the investigated section, which are grouped into 5 limestone units. Radiolitid assemblages, coral–rudist reefs, coral-domi-nated reefs, and hippuritid-dominated reefs are present. The stacking pattern of these reef intervals indicates a general transgressive trend through the entire section. Smaller-scale facies trends could be distinguished within each limestone unit, comprising deepening-upward sequences, defined by a shoreface–calcareous algae–radiolitid–marl facies transition, and shallowing-upward sequences defined by a hippuritid–actaeonellid–coral/rudist facies transition. This cyclic sedimentation pattern is obscured by an episodic input of clastic sediments

derived from the uplifting Sierra Madre Oriental, which in turn triggered either the development or decline of reefs.

【 授权许可】

Unknown