--> Integrated Work Flow for Stratigraphic, Paleoclimate, Provenance Analysis And Prediction (Gulf of Mexico)

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Integrated Work Flow for Stratigraphic, Paleoclimate, Provenance Analysis And Prediction (Gulf of Mexico)

Abstract

The Gulf of Mexico (GoM) is tectonostratigraphically complex with heterogenous turbidite systems feeding across slope sub-basins heavily influenced by salt tectonics, leading to complex architectural stacking patterns, and hampering the identification of comparative stratigraphy. The overwhelming number of wells and corresponding large microfossil datasets in the GoM lend the use of data analytics techniques. Multivariate investigative techniques remove focus from taxa with little or no variance, and highlight taxa with significant variance that reflect evolutionary, paleoecologic, and/or environmental changes. Subtle microfossil distribution patterns, mainly abundance events, play a significant role in refining the reservoir scale biostratigraphy at the field scale. Such techniques can expose microfossil distribution patterns, useful in regional stratigraphic correlation and paleoenvironment interpretation. The analysis of the rock accumulation rate in many wells in the Miocene play showed that only a few condensed sections, probably related to sea-level highstands or system abandonment, can be identified. As such, a limited number of mega-sequences can be predicted at a regional scale. Intra-slope sub-basin scale investigation of the relationship between rock accumulation rate and geologic time, coupled with the analysis of areal distribution of various microfossil taxa, including transported/ reworked material, may help understand the spatial distribution of depositional environments, and thus become viable prediction tools within slope settings. Analysis of marine microfossils is often part of paleoclimate studies. Global cooling and warming events are reflected by certain taxa and their abundances. Terrestrial taxa such as spore and pollen entering the marine realm via fluvial system can help better understand sediment provenance and hinterland climate. Using a spore-pollen analog database, we determined that Lower Eocene sandstones in Alaminos Canyon are sourced from dry and hot areas, whereas those in Keathley Canyon and Walker Ridge come from more temperate hinterlands, allowing for the refinement of play fairways. Biostratigraphy itself can give some geological answers, and support answers provided by other disciplines. Only an integrated approach of multiple subsurface disciplines can reduce uncertainty and produce as robust an answer as possible