Abstract
AbstractThis paper introduces an integrated Neogene microfossil biostratigraphic chart developed within post-merger BP for the Gulf of Mexico Basin and is the first published industrial framework “fully-tuned” to orbital periodicities. Astronomical-tuning was accomplished through a 15-year research program on the Ocean Drilling Program’s (ODP) Leg 154 sediments (offshore NE Brazil) with sampling resolution for calcareous nannofossils and planktonic foraminifera ∼20 k.y. and 40 k.y. (thousand year), respectively. This framework extends from the Late Oligocene (25.05 Ma) to Recent at an average Chart Horizon resolution for the Neogene of 144 k.y., approximately double that of published Gulf of Mexico biostratigraphic charts and a fivefold increase over the highest resolution global calcareous microfossil biozonation. Such resolution approximates that of fourth to fifth order parasequences and is a critical component in the verification of seismic correlations between mini-basins in the deep-water Gulf of Mexico. Its utility in global time-scale construction and correlation has been proven, in part, by application of the scheme in full to internal research for the Oligocene–Miocene boundary interval on the global boundary stratotype section and point (GSSP) in northern Italy and offshore wells in the eastern Mediterranean Sea. This step change in Neogene resolution, now at the level of cyclostratigraphy (the orbital periodicity of eccentricity) and the magnetostratigraphic chron, demonstrates the potential for calcareous microfossil biostratigraphy to more consistently reinforce correlations of these time scale parameters. The integration of microfossil disciplines, consistent taxonomies, and rigorous analytical methodologies are all critical to obtaining and reproducing this new level of biostratigraphic resolution.
Highlights
Microfossils are an important, arguably integral tool in subsurface petroleum exploration
The BP Gulf of Mexico Neogene Astronomically-tuned Time Scale (BP GNATTS) is presented in Figure 2 and a more detailed digital version is available in the Supplementary Materials (Table S1)
We have chosen a twofold division of the Cenozoic, referring the Miocene through Holocene Series (Epochs) to the Neogene, following decades of conventional use in marine micropaleontology and that advocated by Hilgen et al (2012) for the Neogene Period
Summary
Microfossils are an important, arguably integral tool in subsurface petroleum exploration. Application of published Cenozoic global biozonations (Blow, 1969; Martini, 1971; Okada and Bukry, 1980) in deep-water exploration was not ideal, especially with the combined effects produced by sediment dilution on microfossil recovery, different taxonomic concepts, and varied methodologies This necessitated improvement beyond published global biozona tions and stimulated petroleum companies to support research that improved their biostratigraphic databases and frameworks. Integrated Gulf of Mexico (GoM) industrial biostratigraphies and published global biozonations utilizing these two planktonic groups date back half a century, near the inception of a research coring program in the world’s deep-sea basins (Deep Sea Drilling Project). During this time, many industrial staffs dedicated to the GoM developed their own internal Cenozoic biostratigraphic frameworks. The Deep Sea Drilling Project (DSDP) was later rebranded the Ocean Drilling Program (ODP) in 1983 and the Integrated Ocean Drilling Program (IODP) from 2003 to 2013
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
