Extremely High Methane Concentration in Bottom Water and Cored Sediments from Offshore Southwestern Taiwan
It has been found that Bottom Simulating Reflections (BSRs), which infer the existence of potential gas hydrates underneath seafloor sediments, are widely distributed in offshore southwestern Taiwan. Fluids and gases derived from dissociation of gas hydrates, which are typically methane enriched, af...
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| Format: | Article |
| Language: | English |
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Springer
2006-01-01
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| Series: | Terrestrial, Atmospheric and Oceanic Sciences |
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| Online Access: |
http://tao.cgu.org.tw/images/attachments/v174p903.pdf
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| _version_ | 1818008459636899840 |
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| author | Pei-Chuan Chuang Tsanyao Frank Yang Saulwood Lin Hsiao-Fen Lee Tefang F. Lan Wei-Li Hong Char-Shine Liu Ju-Chin Chen Yunshuen Wang |
| author_facet | Pei-Chuan Chuang Tsanyao Frank Yang Saulwood Lin Hsiao-Fen Lee Tefang F. Lan Wei-Li Hong Char-Shine Liu Ju-Chin Chen Yunshuen Wang |
| author_sort | Pei-Chuan Chuang |
| collection | DOAJ |
| description | It has been found that Bottom Simulating Reflections (BSRs), which infer the existence of potential gas hydrates underneath seafloor sediments, are widely distributed in offshore southwestern Taiwan. Fluids and gases derived from dissociation of gas hydrates, which are typically methane enriched, affect the composition of seawater and sediments near venting areas. Hence, methane concentration of seawater and sediments become useful proxies for exploration of potential gas hydrates in a given area. We systematically collected bottom waters and sedimentary core samples for dissolved and pore-space gas analyses through five cruises: ORI-697, ORI-718, ORII-1207, ORII-1230, and ORI-732 from 2003 to 2005 in this study. Some sites with extremely high methane concentrations have been found in offshore southwestern Taiwan, e.g., sites G23 of ORI-697, N8 of ORI-718, and G96 of ORI-732. The methane concentrations of cored sediments display an increasing trend with depth. Furthermore, the down-core profiles of methane and sulfate reveal very shallow depths of sulfate methane interface (SMI) at some sites in this study. It implies sulfate reduction being mainly driven by the process of anaerobic methane oxidation (AMO) in sediments; thus indicating that there is a methane-enriched venting source, which may be the product of dissociation of gas hydrates in this area. |
| first_indexed | 2024-04-14T05:29:31Z |
| format | Article |
| id | doaj.art-cd9470665c9d43e39cfd02360d0cf69d |
| institution | Directory Open Access Journal |
| issn | 1017-0839 2311-7680 |
| language | English |
| last_indexed | 2024-04-14T05:29:31Z |
| publishDate | 2006-01-01 |
| publisher | Springer |
| record_format | Article |
| series | Terrestrial, Atmospheric and Oceanic Sciences |
| spelling | doaj.art-cd9470665c9d43e39cfd02360d0cf69d2022-12-22T02:09:52ZengSpringerTerrestrial, Atmospheric and Oceanic Sciences1017-08392311-76802006-01-0117490310.3319/TAO.2006.17.4.903(GH)Extremely High Methane Concentration in Bottom Water and Cored Sediments from Offshore Southwestern TaiwanPei-Chuan ChuangTsanyao Frank YangSaulwood LinHsiao-Fen LeeTefang F. LanWei-Li HongChar-Shine LiuJu-Chin ChenYunshuen WangIt has been found that Bottom Simulating Reflections (BSRs), which infer the existence of potential gas hydrates underneath seafloor sediments, are widely distributed in offshore southwestern Taiwan. Fluids and gases derived from dissociation of gas hydrates, which are typically methane enriched, affect the composition of seawater and sediments near venting areas. Hence, methane concentration of seawater and sediments become useful proxies for exploration of potential gas hydrates in a given area. We systematically collected bottom waters and sedimentary core samples for dissolved and pore-space gas analyses through five cruises: ORI-697, ORI-718, ORII-1207, ORII-1230, and ORI-732 from 2003 to 2005 in this study. Some sites with extremely high methane concentrations have been found in offshore southwestern Taiwan, e.g., sites G23 of ORI-697, N8 of ORI-718, and G96 of ORI-732. The methane concentrations of cored sediments display an increasing trend with depth. Furthermore, the down-core profiles of methane and sulfate reveal very shallow depths of sulfate methane interface (SMI) at some sites in this study. It implies sulfate reduction being mainly driven by the process of anaerobic methane oxidation (AMO) in sediments; thus indicating that there is a methane-enriched venting source, which may be the product of dissociation of gas hydrates in this area. http://tao.cgu.org.tw/images/attachments/v174p903.pdf MethaneGas hydrateSulfate methane interfaceAnaerobic methane oxidation |
| spellingShingle | Pei-Chuan Chuang Tsanyao Frank Yang Saulwood Lin Hsiao-Fen Lee Tefang F. Lan Wei-Li Hong Char-Shine Liu Ju-Chin Chen Yunshuen Wang Extremely High Methane Concentration in Bottom Water and Cored Sediments from Offshore Southwestern Taiwan Terrestrial, Atmospheric and Oceanic Sciences Methane Gas hydrate Sulfate methane interface Anaerobic methane oxidation |
| title | Extremely High Methane Concentration in Bottom Water and Cored Sediments from Offshore Southwestern Taiwan |
| title_full | Extremely High Methane Concentration in Bottom Water and Cored Sediments from Offshore Southwestern Taiwan |
| title_fullStr | Extremely High Methane Concentration in Bottom Water and Cored Sediments from Offshore Southwestern Taiwan |
| title_full_unstemmed | Extremely High Methane Concentration in Bottom Water and Cored Sediments from Offshore Southwestern Taiwan |
| title_short | Extremely High Methane Concentration in Bottom Water and Cored Sediments from Offshore Southwestern Taiwan |
| title_sort | extremely high methane concentration in bottom water and cored sediments from offshore southwestern taiwan |
| topic | Methane Gas hydrate Sulfate methane interface Anaerobic methane oxidation |
| url |
http://tao.cgu.org.tw/images/attachments/v174p903.pdf
|
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