Disentangling Diagenesis From the Rock Record: An Example From the Permo-Triassic Wordie Creek Formation, East Greenland
The measurement of isotope ratios in sedimentary rocks deposited over geological time can provide key insights to past environmental change over important intervals in the past. However, it is important to be aware that secondary alteration can overprint the original isotopic records. We demonstrate...
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ftucambridgeesc:oai:eprints.esc.cam.ac.uk:4388 2023-05-15T16:03:37+02:00 Disentangling Diagenesis From the Rock Record: An Example From the Permo-Triassic Wordie Creek Formation, East Greenland Roberts, J. Turchyn, A. V. Wignall, P. B. Newton, R. J. Vane, C. H. 2018 text http://eprints.esc.cam.ac.uk/4388/ http://eprints.esc.cam.ac.uk/4388/1/2017GC007259 https://doi.org/10.1002/2017GC007259 en eng AGU http://eprints.esc.cam.ac.uk/4388/1/2017GC007259 Roberts, J. and Turchyn, A. V. and Wignall, P. B. and Newton, R. J. and Vane, C. H. (2018) Disentangling Diagenesis From the Rock Record: An Example From the Permo-Triassic Wordie Creek Formation, East Greenland. Geochemistry, Geophysics, Geosystems, 19 (1). pp. 99-113. ISSN 15252027 DOI https://doi.org/10.1002/2017GC007259 <https://doi.org/10.1002/2017GC007259> 01 - Climate Change and Earth-Ocean Atmosphere Systems Article PeerReviewed 2018 ftucambridgeesc https://doi.org/10.1002/2017GC007259 2020-08-27T18:10:00Z The measurement of isotope ratios in sedimentary rocks deposited over geological time can provide key insights to past environmental change over important intervals in the past. However, it is important to be aware that secondary alteration can overprint the original isotopic records. We demonstrate this principle using high‐resolution carbon, sulfur, and oxygen isotope measurements in organic carbon, pyrite, and carbonate minerals (δ13Corg, δ34Spyr, δ34SCAS, δ13Ccarb, and δ18Ocarb) and kerogen analyses (HI and OI) from the Wordie Creek Formation, East Greenland. These sediments were initially deposited across the Permo‐Triassic transition, but as we will show, the carbonate record has been altered by interaction with meteoric water significantly after initial deposition. Comparison of the better preserved organic carbon and pyrite records with a proximal Permo‐Triassic sequence reveals significant pyrite‐sulfur isotope variability across the Permo‐Triassic transition. This regional heterogeneity argues against basin‐wide euxinia and instead suggests localized changes in sulfur fractionation in response to variations in organic carbon flux. This hypothesis can be used to explain seemingly inconsistent regional trends in other sulfur isotopes across the Permo‐Triassic transition. Plain Language Summary Much of what is known about environmental change in the past has been determined through measuring the chemical properties of rocks. In this study, we demonstrate how those chemical properties may have been altered by processes occurring millions of years later. We show new chemical records from rocks deposited during across the Permo‐Triassic boundary (the world's largest mass extinction event) in East Greenland and discuss how some of the records have been altered by interaction with rain water millions of years after they were deposited. Finally, we talk about the records that have been unaffected by alteration, and what they imply for environmental changes occurring across the Permo‐Triassic boundary. Article in Journal/Newspaper East Greenland Greenland University of Cambridge, Department of Earth Sciences: ESC Publications Greenland Wordie ENVELOPE(-67.500,-67.500,-69.167,-69.167) Geochemistry, Geophysics, Geosystems 19 1 99 113 |
institution |
Open Polar |
collection |
University of Cambridge, Department of Earth Sciences: ESC Publications |
op_collection_id |
ftucambridgeesc |
language |
English |
topic |
01 - Climate Change and Earth-Ocean Atmosphere Systems |
spellingShingle |
01 - Climate Change and Earth-Ocean Atmosphere Systems Roberts, J. Turchyn, A. V. Wignall, P. B. Newton, R. J. Vane, C. H. Disentangling Diagenesis From the Rock Record: An Example From the Permo-Triassic Wordie Creek Formation, East Greenland |
topic_facet |
01 - Climate Change and Earth-Ocean Atmosphere Systems |
description |
The measurement of isotope ratios in sedimentary rocks deposited over geological time can provide key insights to past environmental change over important intervals in the past. However, it is important to be aware that secondary alteration can overprint the original isotopic records. We demonstrate this principle using high‐resolution carbon, sulfur, and oxygen isotope measurements in organic carbon, pyrite, and carbonate minerals (δ13Corg, δ34Spyr, δ34SCAS, δ13Ccarb, and δ18Ocarb) and kerogen analyses (HI and OI) from the Wordie Creek Formation, East Greenland. These sediments were initially deposited across the Permo‐Triassic transition, but as we will show, the carbonate record has been altered by interaction with meteoric water significantly after initial deposition. Comparison of the better preserved organic carbon and pyrite records with a proximal Permo‐Triassic sequence reveals significant pyrite‐sulfur isotope variability across the Permo‐Triassic transition. This regional heterogeneity argues against basin‐wide euxinia and instead suggests localized changes in sulfur fractionation in response to variations in organic carbon flux. This hypothesis can be used to explain seemingly inconsistent regional trends in other sulfur isotopes across the Permo‐Triassic transition. Plain Language Summary Much of what is known about environmental change in the past has been determined through measuring the chemical properties of rocks. In this study, we demonstrate how those chemical properties may have been altered by processes occurring millions of years later. We show new chemical records from rocks deposited during across the Permo‐Triassic boundary (the world's largest mass extinction event) in East Greenland and discuss how some of the records have been altered by interaction with rain water millions of years after they were deposited. Finally, we talk about the records that have been unaffected by alteration, and what they imply for environmental changes occurring across the Permo‐Triassic boundary. |
format |
Article in Journal/Newspaper |
author |
Roberts, J. Turchyn, A. V. Wignall, P. B. Newton, R. J. Vane, C. H. |
author_facet |
Roberts, J. Turchyn, A. V. Wignall, P. B. Newton, R. J. Vane, C. H. |
author_sort |
Roberts, J. |
title |
Disentangling Diagenesis From the Rock Record: An Example From the Permo-Triassic Wordie Creek Formation, East Greenland |
title_short |
Disentangling Diagenesis From the Rock Record: An Example From the Permo-Triassic Wordie Creek Formation, East Greenland |
title_full |
Disentangling Diagenesis From the Rock Record: An Example From the Permo-Triassic Wordie Creek Formation, East Greenland |
title_fullStr |
Disentangling Diagenesis From the Rock Record: An Example From the Permo-Triassic Wordie Creek Formation, East Greenland |
title_full_unstemmed |
Disentangling Diagenesis From the Rock Record: An Example From the Permo-Triassic Wordie Creek Formation, East Greenland |
title_sort |
disentangling diagenesis from the rock record: an example from the permo-triassic wordie creek formation, east greenland |
publisher |
AGU |
publishDate |
2018 |
url |
http://eprints.esc.cam.ac.uk/4388/ http://eprints.esc.cam.ac.uk/4388/1/2017GC007259 https://doi.org/10.1002/2017GC007259 |
long_lat |
ENVELOPE(-67.500,-67.500,-69.167,-69.167) |
geographic |
Greenland Wordie |
geographic_facet |
Greenland Wordie |
genre |
East Greenland Greenland |
genre_facet |
East Greenland Greenland |
op_relation |
http://eprints.esc.cam.ac.uk/4388/1/2017GC007259 Roberts, J. and Turchyn, A. V. and Wignall, P. B. and Newton, R. J. and Vane, C. H. (2018) Disentangling Diagenesis From the Rock Record: An Example From the Permo-Triassic Wordie Creek Formation, East Greenland. Geochemistry, Geophysics, Geosystems, 19 (1). pp. 99-113. ISSN 15252027 DOI https://doi.org/10.1002/2017GC007259 <https://doi.org/10.1002/2017GC007259> |
op_doi |
https://doi.org/10.1002/2017GC007259 |
container_title |
Geochemistry, Geophysics, Geosystems |
container_volume |
19 |
container_issue |
1 |
container_start_page |
99 |
op_container_end_page |
113 |
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1766399306813669376 |