Synchronizing early Eocene deep-sea and continental records from the Bighorn Basin Coring Project, supplement to: Westerhold, Thomas; Röhl, Ursula; Wilkens, Roy H; Gingerich, Philip D; Clyde, William C; Wing, Scott L; Bowen, Gabriel J; Kraus, Mary J (2018): Synchronizing early Eocene deep-sea and continental records - cyclostratigraphic age models for the Bighorn Basin Coring Project drill cores. Climate of the Past, 14(3), 303-319


A consistent chronostratigraphic framework is required to understand the effect of major paleoclimate perturbations on both marine and terrestrial ecosystems. Transient global warming events in the early Eocene, 56-54 Ma ago, show the impact of large scale carbon input into the ocean-atmosphere system. Here we provide the first time-scale synchronization of continental and marine deposits spanning the Paleocene-Eocene Thermal Maximum (PETM) and the interval just prior to the Eocene Thermal Maximum 2 (ETM-2). Cyclic variations in geochemical data come from continental drill cores of the Bighorn Basin Coring Project (BBCP, Wyoming, USA) and from marine deep-sea drilling deposits retrieved by the Ocean Drilling Program (ODP). Both are dominated by eccentricity modulated precession cycles used to construct a common cyclostratigraphic framework. Integration of age models results in a revised astrochronology for the PETM in deep-sea records that is now generally consistent with independent 3He age models. The duration of the PETM is estimated at ~200 kyr for the CIE and ~120 kyr for the associated pelagic clay layer. A common terrestrial and marine age model shows a concurrent major change in marine and terrestrial biotas ~200 kyr before ETM-2. In the Bighorn Basin, the change is referred to as Biohorizon B, and represents a period of significant mammalian turnover and immigration, separating the upper Haplomylus-Ectocion Range Zone from the Bunophorus Interval Zone and approximating the Wa-4-Wa-5 land mammal zone boundary. In sediments from ODP Site 1262 (Walvis Ridge), major changes in the biota at this time are documented by the radiation of a "2nd generation" of apical spine-bearing sphenoliths species (e.g., S. radians and S. editus), the emergence of T. orthostylus, and the marked decline of D. multiradiatus.

Metadata Access
Creator Wilkens, Roy H;Kraus, Mary J;Wing, Scott L;Westerhold, Thomas;Bowen, Gabriel J;Clyde, William C;Gingerich, Philip D;Röhl, Ursula
Publisher PANGAEA - Data Publisher for Earth & Environmental Science
Publication Year 2017
Rights Creative Commons Attribution 3.0 Unported (CC-BY)
Language English
Resource Type Supplementary Collection of Datasets
Format application/zip
Discipline Earth System Research
Spatial Coverage (44N-45N,109W-108W)
Temporal Point 2011-01-08T11:59:59Z