Continental hydroclimate during the late Paleocene-early Eocene in the central Rockies: insights from sedimentological and geochemical records preserved in the greater Green River Basin, southwestern Wyoming, U.S.A.

The late Paleocene to early Eocene (LPEE, ∼59–50 Ma) greenhouse condition is the most recent geologic analogue for future climate change induced by increased atmospheric CO2 partial pressure (pCO2). Recognition of the hyperthermals and reconstruction of the continental hydroclimate and atmospheric p...

Full description

Saved in:
Bibliographic Details
Main Authors: Min Gao, Majie Fan, Guangsheng Zhuang, Domenico Chiarella
Format: Article
Language:English
Published: Frontiers Media S.A. 2025-07-01
Series:Frontiers in Earth Science
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/feart.2025.1507500/full
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849714867996459008
author Min Gao
Min Gao
Min Gao
Majie Fan
Guangsheng Zhuang
Domenico Chiarella
author_facet Min Gao
Min Gao
Min Gao
Majie Fan
Guangsheng Zhuang
Domenico Chiarella
author_sort Min Gao
collection DOAJ
description The late Paleocene to early Eocene (LPEE, ∼59–50 Ma) greenhouse condition is the most recent geologic analogue for future climate change induced by increased atmospheric CO2 partial pressure (pCO2). Recognition of the hyperthermals and reconstruction of the continental hydroclimate and atmospheric pCO2 during this warm period are fundamental to the understanding of Earth’s surface responses to high atmospheric pCO2. Here we study paleosol morphology, bulk organic matter δ13Corg, leaf wax n-alkanes δ13Cn-alk and δDn-alk, and reconstruct mean annual precipitation (MAP) and atmospheric pCO2 from the fine-grained floodplain deposits in the greater Green River Basin, western U.S.A., to examine the hydroclimate evolution in the continental interior during the LPEE. The Paleocene-Eocene Thermal Maximum (PETM) was identified as a ∼4‰–5‰ negative carbon isotope excursion (CIE) in the bulk organic δ13Corg record and leaf wax n-alkanes δ13Cn-alk record, and a 30‰–50‰ increase in leaf wax n-alkanes δDn-alk record. Well drained green paleosols and water-logged histosols dominated the floodplain deposition during the LPEE, and poorly drained red paleosols and carbonate-rich calcisols characterized the hyperthermal. Our reconstructed MAP is generally high (800–1,500 mm) during the LPEE and does not show significant change during the PETM. Our estimated atmospheric pCO2, by integrating bulk organic δ13Corg and paleosol carbonate δ13Cc values, is generally in the range of 600–900 ppm during the early Eocene, 1–2 times higher than the preindustrial level. These records suggest that the continental hydroclimate was generally humid and warm during the LPEE, and transient drying likely happened during the PETM.
format Article
id doaj-art-be73c4fac6ea48808b9814c0fd3a72ba
institution DOAJ
issn 2296-6463
language English
publishDate 2025-07-01
publisher Frontiers Media S.A.
record_format Article
series Frontiers in Earth Science
spelling doaj-art-be73c4fac6ea48808b9814c0fd3a72ba2025-08-20T03:13:35ZengFrontiers Media S.A.Frontiers in Earth Science2296-64632025-07-011310.3389/feart.2025.15075001507500Continental hydroclimate during the late Paleocene-early Eocene in the central Rockies: insights from sedimentological and geochemical records preserved in the greater Green River Basin, southwestern Wyoming, U.S.A.Min Gao0Min Gao1Min Gao2Majie Fan3Guangsheng Zhuang4Domenico Chiarella5Research Institute of Petroleum Exploration and Development, PetroChina, Beijing, ChinaDepartment of Earth and Environmental Sciences, The University of Texas at Arlington, Arlington, TX, United StatesDepartment of Earth Sciences, Royal Holloway, University of London, Egham, United KingdomDepartment of Earth and Environmental Sciences, The University of Texas at Arlington, Arlington, TX, United StatesDepartment of Geology and Geophysics, Louisiana State University, Baton Rouge, LA, United StatesDepartment of Earth Sciences, Royal Holloway, University of London, Egham, United KingdomThe late Paleocene to early Eocene (LPEE, ∼59–50 Ma) greenhouse condition is the most recent geologic analogue for future climate change induced by increased atmospheric CO2 partial pressure (pCO2). Recognition of the hyperthermals and reconstruction of the continental hydroclimate and atmospheric pCO2 during this warm period are fundamental to the understanding of Earth’s surface responses to high atmospheric pCO2. Here we study paleosol morphology, bulk organic matter δ13Corg, leaf wax n-alkanes δ13Cn-alk and δDn-alk, and reconstruct mean annual precipitation (MAP) and atmospheric pCO2 from the fine-grained floodplain deposits in the greater Green River Basin, western U.S.A., to examine the hydroclimate evolution in the continental interior during the LPEE. The Paleocene-Eocene Thermal Maximum (PETM) was identified as a ∼4‰–5‰ negative carbon isotope excursion (CIE) in the bulk organic δ13Corg record and leaf wax n-alkanes δ13Cn-alk record, and a 30‰–50‰ increase in leaf wax n-alkanes δDn-alk record. Well drained green paleosols and water-logged histosols dominated the floodplain deposition during the LPEE, and poorly drained red paleosols and carbonate-rich calcisols characterized the hyperthermal. Our reconstructed MAP is generally high (800–1,500 mm) during the LPEE and does not show significant change during the PETM. Our estimated atmospheric pCO2, by integrating bulk organic δ13Corg and paleosol carbonate δ13Cc values, is generally in the range of 600–900 ppm during the early Eocene, 1–2 times higher than the preindustrial level. These records suggest that the continental hydroclimate was generally humid and warm during the LPEE, and transient drying likely happened during the PETM.https://www.frontiersin.org/articles/10.3389/feart.2025.1507500/fullcarbon isotopeleaf wax n-alkanespaleosolprecipitationpCO2Paleocene-Eocene Thermal Maximum
spellingShingle Min Gao
Min Gao
Min Gao
Majie Fan
Guangsheng Zhuang
Domenico Chiarella
Continental hydroclimate during the late Paleocene-early Eocene in the central Rockies: insights from sedimentological and geochemical records preserved in the greater Green River Basin, southwestern Wyoming, U.S.A.
Frontiers in Earth Science
carbon isotope
leaf wax n-alkanes
paleosol
precipitation
pCO2
Paleocene-Eocene Thermal Maximum
title Continental hydroclimate during the late Paleocene-early Eocene in the central Rockies: insights from sedimentological and geochemical records preserved in the greater Green River Basin, southwestern Wyoming, U.S.A.
title_full Continental hydroclimate during the late Paleocene-early Eocene in the central Rockies: insights from sedimentological and geochemical records preserved in the greater Green River Basin, southwestern Wyoming, U.S.A.
title_fullStr Continental hydroclimate during the late Paleocene-early Eocene in the central Rockies: insights from sedimentological and geochemical records preserved in the greater Green River Basin, southwestern Wyoming, U.S.A.
title_full_unstemmed Continental hydroclimate during the late Paleocene-early Eocene in the central Rockies: insights from sedimentological and geochemical records preserved in the greater Green River Basin, southwestern Wyoming, U.S.A.
title_short Continental hydroclimate during the late Paleocene-early Eocene in the central Rockies: insights from sedimentological and geochemical records preserved in the greater Green River Basin, southwestern Wyoming, U.S.A.
title_sort continental hydroclimate during the late paleocene early eocene in the central rockies insights from sedimentological and geochemical records preserved in the greater green river basin southwestern wyoming u s a
topic carbon isotope
leaf wax n-alkanes
paleosol
precipitation
pCO2
Paleocene-Eocene Thermal Maximum
url https://www.frontiersin.org/articles/10.3389/feart.2025.1507500/full
work_keys_str_mv AT mingao continentalhydroclimateduringthelatepaleoceneearlyeoceneinthecentralrockiesinsightsfromsedimentologicalandgeochemicalrecordspreservedinthegreatergreenriverbasinsouthwesternwyomingusa
AT mingao continentalhydroclimateduringthelatepaleoceneearlyeoceneinthecentralrockiesinsightsfromsedimentologicalandgeochemicalrecordspreservedinthegreatergreenriverbasinsouthwesternwyomingusa
AT mingao continentalhydroclimateduringthelatepaleoceneearlyeoceneinthecentralrockiesinsightsfromsedimentologicalandgeochemicalrecordspreservedinthegreatergreenriverbasinsouthwesternwyomingusa
AT majiefan continentalhydroclimateduringthelatepaleoceneearlyeoceneinthecentralrockiesinsightsfromsedimentologicalandgeochemicalrecordspreservedinthegreatergreenriverbasinsouthwesternwyomingusa
AT guangshengzhuang continentalhydroclimateduringthelatepaleoceneearlyeoceneinthecentralrockiesinsightsfromsedimentologicalandgeochemicalrecordspreservedinthegreatergreenriverbasinsouthwesternwyomingusa
AT domenicochiarella continentalhydroclimateduringthelatepaleoceneearlyeoceneinthecentralrockiesinsightsfromsedimentologicalandgeochemicalrecordspreservedinthegreatergreenriverbasinsouthwesternwyomingusa