Mexican archives for the major Cretaceous Oceanic Anoxic Events

摘要: Oceanic Anoxic Events (OAEs) are interpreted as brief episodes of oxygen-depleted conditions in the global ocean that resulted from profound perturbations carbon cycle. These events favored widespread deposition organic carbon-rich sediments and subsequent formation hydrocarbon source rocks. The most important these for Cretaceous period globally recognized OAE 1a (early Aptian, Selli event), 2 (Cenomanian/Turonian boundary, Bonarelli Atlantic-restricted 3 (Coniacian/Santonian boundary). In Mexico, several sedimentary successions ages proved rocks potential targets oil gas shale exploration; however, cases, it is unknown how influenced redox under which they were deposited. general, there little research to document characterize properly events. This work exposes analyzes current state study proposes new stratigraphic units prospect methodologies further studies. has been isotopically constrained northeastern part country within with high content lowermost La Pena Formation. However, recent suggests base Formation seems isochronous younger than 1a. Accordingly, this event must be recorded underlying Cupido/Lower Tamaulipas formations. Because its age lithostratigraphic features, Agua Salada Lampazos Platform also linked event. documented Mexico Nueva Indidura formations, southern uppermost Morelos Trace metal enrichment indicates emplacement Caribbean plateau probably played an role record anoxic across Mexico. Poorly oxygenated during Cenomanian/Turonian lasted until early Coniacian. Other Nueva, Eagle Ford, Soyatal, Maltrata remains unknown. We hypothesize Coniacian/Santonian Mexican paleogeography pattern could trigger at least intermittent anoxic/dysoxic favorable burial, suggest searching San Felipe, or Austin