Queries about biogenesis of Quaternary gas in Qaidam Basin, NW China

Abstract: Organic geochemistry of Quaternary source rocks is not favorable to the generation of natural gas, such as the low organic matter content, the thin layer, and the low ethanoic acid content in mudstones. Seven cases of natural gas occurrences show that the gas genesis cannot be recognized b...

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Main Authors: Long MA, Hong-de CHEN, Jing-lian ZHANG, Lan-ting SHI, Ping-sheng WEI
Format: Article
Language:English
Published: KeAi Communications Co., Ltd. 2008-04-01
Series:Petroleum Exploration and Development
Online Access:http://www.sciencedirect.com/science/article/pii/S1876380408600348
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author Long MA
Hong-de CHEN
Jing-lian ZHANG
Lan-ting SHI
Ping-sheng WEI
author_facet Long MA
Hong-de CHEN
Jing-lian ZHANG
Lan-ting SHI
Ping-sheng WEI
author_sort Long MA
collection DOAJ
description Abstract: Organic geochemistry of Quaternary source rocks is not favorable to the generation of natural gas, such as the low organic matter content, the thin layer, and the low ethanoic acid content in mudstones. Seven cases of natural gas occurrences show that the gas genesis cannot be recognized by the current carbon isotope compositions. Five simulation experiments show that carbon isotopic fractionation can also happen in the Fischer-Tropsch reaction. Carbon isotope is not a reliable criterion for distinguishing biogenic from abiogenic gases. Based on 2 geo-transects and electromagnetic soundings, there is an uplifting upper mantle and 3 ultra-deep faults in the deeper crust, and there is a low velocity–high conductive layer in the mid crust, which is rich in CO2 (CO) and H2. If metal catalytic elements participated, the Fischer–Tropsch reaction might have occurred and formed hydrocarbons under certain temperatures and pressures. The deep crust structure shows that abiogenic gas might exist under the Quaternary System in the Qaidam Basin. Key words: biogenic gas, carbon isotope, fractionation, Fischer-Tropsch reaction, Quaternary, Qaidam Basin
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spelling doaj.art-97624f76e59c43caa132b56f9a8698472022-12-21T17:12:45ZengKeAi Communications Co., Ltd.Petroleum Exploration and Development1876-38042008-04-01352250256Queries about biogenesis of Quaternary gas in Qaidam Basin, NW ChinaLong MA0Hong-de CHEN1Jing-lian ZHANG2Lan-ting SHI3Ping-sheng WEI4School of Sedimentary Geology, Chengdu University of Technology, Chengdu 610059, China; Northwest Branch, Research Institute of Petroleum Exploration and Development, PetroChina, Lanzhou 730020, China; Corresponding authorSchool of Sedimentary Geology, Chengdu University of Technology, Chengdu 610059, ChinaNorthwest Branch, Research Institute of Petroleum Exploration and Development, PetroChina, Lanzhou 730020, ChinaNorthwest Branch, Research Institute of Petroleum Exploration and Development, PetroChina, Lanzhou 730020, ChinaNorthwest Branch, Research Institute of Petroleum Exploration and Development, PetroChina, Lanzhou 730020, ChinaAbstract: Organic geochemistry of Quaternary source rocks is not favorable to the generation of natural gas, such as the low organic matter content, the thin layer, and the low ethanoic acid content in mudstones. Seven cases of natural gas occurrences show that the gas genesis cannot be recognized by the current carbon isotope compositions. Five simulation experiments show that carbon isotopic fractionation can also happen in the Fischer-Tropsch reaction. Carbon isotope is not a reliable criterion for distinguishing biogenic from abiogenic gases. Based on 2 geo-transects and electromagnetic soundings, there is an uplifting upper mantle and 3 ultra-deep faults in the deeper crust, and there is a low velocity–high conductive layer in the mid crust, which is rich in CO2 (CO) and H2. If metal catalytic elements participated, the Fischer–Tropsch reaction might have occurred and formed hydrocarbons under certain temperatures and pressures. The deep crust structure shows that abiogenic gas might exist under the Quaternary System in the Qaidam Basin. Key words: biogenic gas, carbon isotope, fractionation, Fischer-Tropsch reaction, Quaternary, Qaidam Basinhttp://www.sciencedirect.com/science/article/pii/S1876380408600348
spellingShingle Long MA
Hong-de CHEN
Jing-lian ZHANG
Lan-ting SHI
Ping-sheng WEI
Queries about biogenesis of Quaternary gas in Qaidam Basin, NW China
Petroleum Exploration and Development
title Queries about biogenesis of Quaternary gas in Qaidam Basin, NW China
title_full Queries about biogenesis of Quaternary gas in Qaidam Basin, NW China
title_fullStr Queries about biogenesis of Quaternary gas in Qaidam Basin, NW China
title_full_unstemmed Queries about biogenesis of Quaternary gas in Qaidam Basin, NW China
title_short Queries about biogenesis of Quaternary gas in Qaidam Basin, NW China
title_sort queries about biogenesis of quaternary gas in qaidam basin nw china
url http://www.sciencedirect.com/science/article/pii/S1876380408600348
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