Resumen

AGUILAR, Teresita  y  GRANADOS, Raquel. Shallow-water shell deposits affected by storms in the central pacific of Costa Rica, Punta Carballo formation, Miocene. Rev. Geol. Amér. Central [online]. 2018, n.59, pp.57-70. ISSN 0256-7024.  http://dx.doi.org/10.15517/rgac.v59i0.34159.

Outcrops at Doña Ana beach (Punta Carballo Formation, Miocene) exhibit proximal tempestites that formed in a shallow platform environment (protected bay) which was episodically affected by strong storms. The preserved fauna in the first layer is mainly composed of bivalves of the Atrina genus and show evidence of exhumation and reworking. Six shell-rich beds, which overlay the first layer, are comprised of mollusks (bivalves, gastropods and nautiloids), crabs (carapace fragments and pincers), shark teeth, and carbonized wood fragments and range in thickness from centimeters to decimeters. These beds also exhibit characteristic storm-associated structures, such as cross stratification, hummocky cross stratification, positive gradation, orientation, imbrication, filling structures, erosion, and hiatus.

Palabras clave : Paleotempestology; tempestites; shell-beds; storms; Miocene; Costa Rica..

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