Early porosity generation in organic-sulfur-rich mudstones
Abstract High total organic sulfur (TOS) content (i.e., Type IIS kerogen) is well known to significantly influence kerogen transformation but the effect of TOS content on the evolution of organic porosity has only rarely and indirectly been investigated. This study demonstrates that organic porosity...
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Nature Portfolio
2023-06-01
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Series: | Scientific Reports |
Online Access: | https://doi.org/10.1038/s41598-023-35259-5 |
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author | Levi J. Knapp Omid H. Ardakani Julito Reyes Kazuaki Ishikawa |
author_facet | Levi J. Knapp Omid H. Ardakani Julito Reyes Kazuaki Ishikawa |
author_sort | Levi J. Knapp |
collection | DOAJ |
description | Abstract High total organic sulfur (TOS) content (i.e., Type IIS kerogen) is well known to significantly influence kerogen transformation but the effect of TOS content on the evolution of organic porosity has only rarely and indirectly been investigated. This study demonstrates that organic porosity is generated at lower thermal maturity in mudstones containing Type IIS kerogen relative to those with Type II kerogen. To our knowledge this phenomenon has not been previously demonstrated. The implications are relevant for the characterization of organic-rich mudstones as cap rocks, hydrocarbon reservoirs, and disposal reservoirs for CO2 or nuclear waste because pore systems control storage volumes and matrix fluid flow. Five thermally immature core samples were selected from three organic-rich mudstone units with low to high TOS content: the late Devonian Duvernay Formation (Canada), middle late Miocene Onnagawa Formation (Japan), and early Jurassic Gordondale member of the Fernie Formation (Canada). Hydrous pyrolysis was used to artificially mature splits of the immature samples to four maturity stages, upon which petrophysical and organic geochemical properties were measured and compared to baseline immature samples. Most porosity growth in Type IIS samples occurred below 0.70% VRoeqv, but in Type II samples was broader and robust until 1.1% VRoeqv. |
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institution | Directory Open Access Journal |
issn | 2045-2322 |
language | English |
last_indexed | 2024-03-13T03:22:35Z |
publishDate | 2023-06-01 |
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spelling | doaj.art-cbaa1596c8614dea9d6829d51650cf8f2023-06-25T11:17:24ZengNature PortfolioScientific Reports2045-23222023-06-0113112310.1038/s41598-023-35259-5Early porosity generation in organic-sulfur-rich mudstonesLevi J. Knapp0Omid H. Ardakani1Julito Reyes2Kazuaki Ishikawa3Japan Organization for Metals and Energy Security (JOGMEC)Natural Resources Canada, Geological Survey of CanadaNatural Resources Canada, Geological Survey of CanadaJapan Organization for Metals and Energy Security (JOGMEC)Abstract High total organic sulfur (TOS) content (i.e., Type IIS kerogen) is well known to significantly influence kerogen transformation but the effect of TOS content on the evolution of organic porosity has only rarely and indirectly been investigated. This study demonstrates that organic porosity is generated at lower thermal maturity in mudstones containing Type IIS kerogen relative to those with Type II kerogen. To our knowledge this phenomenon has not been previously demonstrated. The implications are relevant for the characterization of organic-rich mudstones as cap rocks, hydrocarbon reservoirs, and disposal reservoirs for CO2 or nuclear waste because pore systems control storage volumes and matrix fluid flow. Five thermally immature core samples were selected from three organic-rich mudstone units with low to high TOS content: the late Devonian Duvernay Formation (Canada), middle late Miocene Onnagawa Formation (Japan), and early Jurassic Gordondale member of the Fernie Formation (Canada). Hydrous pyrolysis was used to artificially mature splits of the immature samples to four maturity stages, upon which petrophysical and organic geochemical properties were measured and compared to baseline immature samples. Most porosity growth in Type IIS samples occurred below 0.70% VRoeqv, but in Type II samples was broader and robust until 1.1% VRoeqv.https://doi.org/10.1038/s41598-023-35259-5 |
spellingShingle | Levi J. Knapp Omid H. Ardakani Julito Reyes Kazuaki Ishikawa Early porosity generation in organic-sulfur-rich mudstones Scientific Reports |
title | Early porosity generation in organic-sulfur-rich mudstones |
title_full | Early porosity generation in organic-sulfur-rich mudstones |
title_fullStr | Early porosity generation in organic-sulfur-rich mudstones |
title_full_unstemmed | Early porosity generation in organic-sulfur-rich mudstones |
title_short | Early porosity generation in organic-sulfur-rich mudstones |
title_sort | early porosity generation in organic sulfur rich mudstones |
url | https://doi.org/10.1038/s41598-023-35259-5 |
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