2 Interdisciplinary Paleontology: New approaches to solving complex paleontological problems (Part I)

Paleontology is increasingly drawing upon insight from other disciplines to solve complex problems and generate more accurate reconstructions of past life. This session will illustrate novel interdisciplinary research and provide tools to develop such approaches.

Monday, 18 May 2026
8:00 AM - 12:00 PM
Alvarado F

Environmental Stabilization and Faunal Diversity in the Earliest Paleogene: Case Study from the Gulf Coastal Plain

Paper number: 2-9
Program: Technical Sessions
Time: 11:00 AM – 11:20 AM

Authors

Abstract

 The Cretaceous-Paleogene (K-Pg) mass extinction resulted in a loss of ~40% of genera and ~76% of species on Earth, driven by the aftermath of the Chicxulub bolide impact into the Yucatán carbonate platform (Hildebrand et al., 1991; Raup and Sepkoski, 1982). Globally, extinction was likely driven by photosynthetic collapse during a short-lived period of dust-induced darkness, while local causes of death also included tsunamis, earthquakes, and falling impact ejecta (Gulick et al., 2019; Morgan et al., 2022). The shutdown of photosynthetic activity, particularly in the shallow ocean, caused a perturbation in the global carbon cycle that can be observed in a carbon isotopic excursion found in most sections containing the K-Pg. Geochemical analysis of the first ~260,000 years (Sosa‐Montes De Oca et al., 2024) after the K-Pg boundary was used here to characterize how shallow marine environments along the Gulf Coast evolved in the aftermath of the extinction, on a timescale not usually captured geologically. Sections were sampled along Trim Cane Creek, Mississippi, a site 1300 km from the impact site, where a series of micro-half-grabens formed during impact seismicity and uniquely expanded sections of earliest Paleogene sediment accumulated. The timing and longevity of carbon cycle overturn was estimated here from bulk sediment δ13C, while δ18O analysis was used to determine the likely degree of diagenetic alteration in the sections. Finally, these geochemical indicators of environmental stabilization were correlated with stratigraphic indicators of diversity rebound—ammonites, dinoflagellates, and nannofossils which have been previously described in the Gulf Coastal Plain in the latest Cretaceous (Larina et al., 2016) and earliest Paleogene (Dastas et al., 2014). Preliminary results suggest that environmental stabilization on the Gulf Coast may have occurred extremely rapidly, within 30-100 Kyrs, which further supports other findings of a return of primary productivity among foraminifera and calcareous nannoplankton within just 30 Kyrs within Chicxulub crater (Lowery et al., 2018).

Geological Society of America Abstracts with Programs. Vol. 58, No. 4

doi: 10.1130/abs/2026RM-410486

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