A paleoenvironmental and ecological analysis of biomarkers from the Eocene Fossil Basin, Green River Formation, U.S.A.

Exceptionally well-preserved fossil specimens in the Fossil Basin of the Green River Formation (GRF) have made it the subject of extensive paleontological study, but the organic molecular framework that evolved during a key paleoclimatic and fossil-bearing interval during the early Eocene is poorly...

Full description

Bibliographic Details
Main Authors: Elson, Amy, Schwark, Lorenz, Whiteside, J.H., Hopper, Peter, Poropat, Stephen, Holman, Alex, Grice, Kliti
Format: Journal Article
Published: 2024
Online Access:http://purl.org/au-research/grants/arc/FL210100103
http://hdl.handle.net/20.500.11937/96070
_version_ 1848766089043902464
author Elson, Amy
Schwark, Lorenz
Whiteside, J.H.
Hopper, Peter
Poropat, Stephen
Holman, Alex
Grice, Kliti
author_facet Elson, Amy
Schwark, Lorenz
Whiteside, J.H.
Hopper, Peter
Poropat, Stephen
Holman, Alex
Grice, Kliti
author_sort Elson, Amy
building Curtin Institutional Repository
collection Online Access
description Exceptionally well-preserved fossil specimens in the Fossil Basin of the Green River Formation (GRF) have made it the subject of extensive paleontological study, but the organic molecular framework that evolved during a key paleoclimatic and fossil-bearing interval during the early Eocene is poorly understood. Whereas the organic geochemistry of the larger co-eval GRF basins has been extensively characterized, our molecular understanding of the fossil-bearing layers in the Fossil Basin and the drivers of the exceptional fossilization therein remain unresolved. To bridge this gap, sediments from the famous 18″-layer — the fossiliferous horizon that is extensively quarried for exceptional soft-tissue fossils — were sampled for organic and isotopic geochemical characterisation. The results show that the Fossil Basin sedimentary archive is geochemically distinct from other GRF basins, as exemplified by the absence of the classical biomarker β-carotane and minimal evidence for the large green algal blooms that predominate in the other GRF lake basins. Photic zone euxinia (PZE), anoxia, and a freshwater cap enabled development of a productive and diverse ecosystem. Salinity and density stratification prevented vertical mixing of the water column and supported preservation of decaying carcasses. In contrast to other GRF basins, the small areal extent and ellipsoid shape of the Fossil Basin focussed terrestrial and freshwater inputs into the lake, resulting in ideal conditions for preservation of an exceptional fossil record.
first_indexed 2025-11-14T11:45:36Z
format Journal Article
id curtin-20.500.11937-96070
institution Curtin University Malaysia
institution_category Local University
last_indexed 2025-11-14T11:45:36Z
publishDate 2024
recordtype eprints
repository_type Digital Repository
spelling curtin-20.500.11937-960702024-11-07T01:06:05Z A paleoenvironmental and ecological analysis of biomarkers from the Eocene Fossil Basin, Green River Formation, U.S.A. Elson, Amy Schwark, Lorenz Whiteside, J.H. Hopper, Peter Poropat, Stephen Holman, Alex Grice, Kliti Exceptionally well-preserved fossil specimens in the Fossil Basin of the Green River Formation (GRF) have made it the subject of extensive paleontological study, but the organic molecular framework that evolved during a key paleoclimatic and fossil-bearing interval during the early Eocene is poorly understood. Whereas the organic geochemistry of the larger co-eval GRF basins has been extensively characterized, our molecular understanding of the fossil-bearing layers in the Fossil Basin and the drivers of the exceptional fossilization therein remain unresolved. To bridge this gap, sediments from the famous 18″-layer — the fossiliferous horizon that is extensively quarried for exceptional soft-tissue fossils — were sampled for organic and isotopic geochemical characterisation. The results show that the Fossil Basin sedimentary archive is geochemically distinct from other GRF basins, as exemplified by the absence of the classical biomarker β-carotane and minimal evidence for the large green algal blooms that predominate in the other GRF lake basins. Photic zone euxinia (PZE), anoxia, and a freshwater cap enabled development of a productive and diverse ecosystem. Salinity and density stratification prevented vertical mixing of the water column and supported preservation of decaying carcasses. In contrast to other GRF basins, the small areal extent and ellipsoid shape of the Fossil Basin focussed terrestrial and freshwater inputs into the lake, resulting in ideal conditions for preservation of an exceptional fossil record. 2024 Journal Article http://hdl.handle.net/20.500.11937/96070 10.1016/j.orggeochem.2024.104830 http://purl.org/au-research/grants/arc/FL210100103 https://creativecommons.org/licenses/by/4.0/ fulltext
spellingShingle Elson, Amy
Schwark, Lorenz
Whiteside, J.H.
Hopper, Peter
Poropat, Stephen
Holman, Alex
Grice, Kliti
A paleoenvironmental and ecological analysis of biomarkers from the Eocene Fossil Basin, Green River Formation, U.S.A.
title A paleoenvironmental and ecological analysis of biomarkers from the Eocene Fossil Basin, Green River Formation, U.S.A.
title_full A paleoenvironmental and ecological analysis of biomarkers from the Eocene Fossil Basin, Green River Formation, U.S.A.
title_fullStr A paleoenvironmental and ecological analysis of biomarkers from the Eocene Fossil Basin, Green River Formation, U.S.A.
title_full_unstemmed A paleoenvironmental and ecological analysis of biomarkers from the Eocene Fossil Basin, Green River Formation, U.S.A.
title_short A paleoenvironmental and ecological analysis of biomarkers from the Eocene Fossil Basin, Green River Formation, U.S.A.
title_sort paleoenvironmental and ecological analysis of biomarkers from the eocene fossil basin, green river formation, u.s.a.
url http://purl.org/au-research/grants/arc/FL210100103
http://hdl.handle.net/20.500.11937/96070