In situ thermal excursions detected in the Nankai Trough forearc slope sediment at IODP NanTroSEIZE Site C0008
Abstract At Integrated Ocean Drilling Program (IODP) Site C0008 in the Nankai Trough slope sediment, we discovered in situ temperature anomalies at 80 to 160 m below the seafloor, where pore fluid Cl and δ 18 O excursions were identified and interpreted as pore fluid refreshing due to hydrate dissoc...
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ftbiomed:oai:biomedcentral.com:s40623-014-0171-1 2023-05-15T17:12:03+02:00 In situ thermal excursions detected in the Nankai Trough forearc slope sediment at IODP NanTroSEIZE Site C0008 Kinoshita, Masataka Fukase, Hiroaki Goto, Shusaku Toki, Tomohiro 2015-02-05 http://www.earth-planets-space.com/content/67/1/16 en eng BioMed Central Ltd. http://www.earth-planets-space.com/content/67/1/16 Copyright 2015 Kinoshita et al.; licensee Springer. NanTroSEIZE Methane hydrate Endothermic Friction Letter 2015 ftbiomed 2015-02-15T00:51:25Z Abstract At Integrated Ocean Drilling Program (IODP) Site C0008 in the Nankai Trough slope sediment, we discovered in situ temperature anomalies at 80 to 160 m below the seafloor, where pore fluid Cl and δ 18 O excursions were identified and interpreted as pore fluid refreshing due to hydrate dissociation. The volume fraction of hydrates is estimated to be approximately 3% and approximately 40% maximum at Holes C0008A and C0008C, respectively. In the vicinity of these anomalies, we discovered negative and positive temperature excursions of up to 1 K measured in situ using the Advanced Piston Corer Temperature (APC-T) tool attached to the shoe of a hydraulic piston corer. They are significantly larger than the uncertainties caused during data acquisition and processing. Frictional heat due to penetration increased the temperature by >10 K, exceeding the gas/hydrate stability temperature at that depth. This heat is partly consumed by hydrate dissociation, which disturbs the thermal decay curve after penetration, but 2D numerical modeling revealed that hydrate dissociation does not significantly change the extrapolated equilibrium temperature. So far, we cannot suggest any acceptable explanation for the observed thermal anomalies, although we strongly suspect that it is related to hydrate dissociation. Manuscript Methane hydrate BioMed Central |
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NanTroSEIZE Methane hydrate Endothermic Friction |
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NanTroSEIZE Methane hydrate Endothermic Friction Kinoshita, Masataka Fukase, Hiroaki Goto, Shusaku Toki, Tomohiro In situ thermal excursions detected in the Nankai Trough forearc slope sediment at IODP NanTroSEIZE Site C0008 |
topic_facet |
NanTroSEIZE Methane hydrate Endothermic Friction |
description |
Abstract At Integrated Ocean Drilling Program (IODP) Site C0008 in the Nankai Trough slope sediment, we discovered in situ temperature anomalies at 80 to 160 m below the seafloor, where pore fluid Cl and δ 18 O excursions were identified and interpreted as pore fluid refreshing due to hydrate dissociation. The volume fraction of hydrates is estimated to be approximately 3% and approximately 40% maximum at Holes C0008A and C0008C, respectively. In the vicinity of these anomalies, we discovered negative and positive temperature excursions of up to 1 K measured in situ using the Advanced Piston Corer Temperature (APC-T) tool attached to the shoe of a hydraulic piston corer. They are significantly larger than the uncertainties caused during data acquisition and processing. Frictional heat due to penetration increased the temperature by >10 K, exceeding the gas/hydrate stability temperature at that depth. This heat is partly consumed by hydrate dissociation, which disturbs the thermal decay curve after penetration, but 2D numerical modeling revealed that hydrate dissociation does not significantly change the extrapolated equilibrium temperature. So far, we cannot suggest any acceptable explanation for the observed thermal anomalies, although we strongly suspect that it is related to hydrate dissociation. |
format |
Manuscript |
author |
Kinoshita, Masataka Fukase, Hiroaki Goto, Shusaku Toki, Tomohiro |
author_facet |
Kinoshita, Masataka Fukase, Hiroaki Goto, Shusaku Toki, Tomohiro |
author_sort |
Kinoshita, Masataka |
title |
In situ thermal excursions detected in the Nankai Trough forearc slope sediment at IODP NanTroSEIZE Site C0008 |
title_short |
In situ thermal excursions detected in the Nankai Trough forearc slope sediment at IODP NanTroSEIZE Site C0008 |
title_full |
In situ thermal excursions detected in the Nankai Trough forearc slope sediment at IODP NanTroSEIZE Site C0008 |
title_fullStr |
In situ thermal excursions detected in the Nankai Trough forearc slope sediment at IODP NanTroSEIZE Site C0008 |
title_full_unstemmed |
In situ thermal excursions detected in the Nankai Trough forearc slope sediment at IODP NanTroSEIZE Site C0008 |
title_sort |
in situ thermal excursions detected in the nankai trough forearc slope sediment at iodp nantroseize site c0008 |
publisher |
BioMed Central Ltd. |
publishDate |
2015 |
url |
http://www.earth-planets-space.com/content/67/1/16 |
genre |
Methane hydrate |
genre_facet |
Methane hydrate |
op_relation |
http://www.earth-planets-space.com/content/67/1/16 |
op_rights |
Copyright 2015 Kinoshita et al.; licensee Springer. |
_version_ |
1766068812177735680 |