Features and origin of natural gas in the Sinian–Cambrian of central Sichuan paleo-uplift, Sichuan Basin, SW China
Based on the new drilling data and field outcrop data of the Gaoshiti–Moxi area, the geochemical characteristics of the Sinian-Cambrian natural gas are studied and analyzed, including gas composition, isotope, light hydrocarbon, kerogen carbon isotope and reservoir bitumen biomarkers etc. The result...
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KeAi Communications Co., Ltd.
2015-12-01
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Series: | Petroleum Exploration and Development |
Online Access: | http://www.sciencedirect.com/science/article/pii/S1876380415300732 |
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English |
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author |
Guoqi WEI Zengye XIE Jiarong SONG Wei YANG Zhihong WANG Jian LI Dongliang WANG Zhisheng LI Wuren XIE |
spellingShingle |
Guoqi WEI Zengye XIE Jiarong SONG Wei YANG Zhihong WANG Jian LI Dongliang WANG Zhisheng LI Wuren XIE Features and origin of natural gas in the Sinian–Cambrian of central Sichuan paleo-uplift, Sichuan Basin, SW China Petroleum Exploration and Development |
author_facet |
Guoqi WEI Zengye XIE Jiarong SONG Wei YANG Zhihong WANG Jian LI Dongliang WANG Zhisheng LI Wuren XIE |
author_sort |
Guoqi WEI |
title |
Features and origin of natural gas in the Sinian–Cambrian of central Sichuan paleo-uplift, Sichuan Basin, SW China |
title_short |
Features and origin of natural gas in the Sinian–Cambrian of central Sichuan paleo-uplift, Sichuan Basin, SW China |
title_full |
Features and origin of natural gas in the Sinian–Cambrian of central Sichuan paleo-uplift, Sichuan Basin, SW China |
title_fullStr |
Features and origin of natural gas in the Sinian–Cambrian of central Sichuan paleo-uplift, Sichuan Basin, SW China |
title_full_unstemmed |
Features and origin of natural gas in the Sinian–Cambrian of central Sichuan paleo-uplift, Sichuan Basin, SW China |
title_sort |
features and origin of natural gas in the sinian–cambrian of central sichuan paleo-uplift, sichuan basin, sw china |
publisher |
KeAi Communications Co., Ltd. |
series |
Petroleum Exploration and Development |
issn |
1876-3804 |
publishDate |
2015-12-01 |
description |
Based on the new drilling data and field outcrop data of the Gaoshiti–Moxi area, the geochemical characteristics of the Sinian-Cambrian natural gas are studied and analyzed, including gas composition, isotope, light hydrocarbon, kerogen carbon isotope and reservoir bitumen biomarkers etc. The results show that: (1) The natural gases of the Sinian Dengying Formation and Cambrian Longwangmiao Formation, mainly composed of hydrocarbon gas, are typical dry gas. However, the natural gas of the Dengying Formation is characterized by higher dry coefficient, lower content of hydrocarbon gas and higher content of non-hydrocarbon gas. The main differences in non-hydrocarbon gases are the contents of N2, CO2, H2S and He, the small composition differences between the natural gas of Dengying Formation and that of Longwangmiao Formation are mainly caused by maturity differences of source rocks and H2S generated by reaction between sulfide mineral and hydrocarbons. (2) There are obvious differences in δ13C2 between the natural gases in Dengying Formation and Longwangmiao Formation, showing different parent materials of them. (3) There are large differences in δ2H between the natural gases of Dengying Formation and Longwangmiao Formation, showing the different water salinities of their source rock depositional environment. (4) The average kerogen carbon isotope values of the Lower Cambrian shale, Dengying Formation mudstone, Doushantuo Formation mudstone and Dengying Formation carbonates are −32.8‰, −31.9‰, −30.7‰ and −27.8‰ respectively. (5) The ratio of 4-methyl dibenzothiophene to 1-methyl dibenzothiophene of Dengying Formation bitumen is between that of Qiongzhusi Formation and Dengying Formation source rocks. It is believed that the Sinian-Cambrian natural gas in the Gaoshiti-Moxi area is mainly oil cracking gas, the Sinian natural gases come from the Sinian and Cambrian source rocks, and the Cambrian natural gases mainly come from Cambrian source rock. Key words: natural gas feature, gas genesis, Sinian, Cambrian, central Sichuan paleo-uplift, Sichuan Basin |
url |
http://www.sciencedirect.com/science/article/pii/S1876380415300732 |
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doaj-daac838224fb4b09bedaf56f0eeedeed2021-02-02T04:47:07ZengKeAi Communications Co., Ltd.Petroleum Exploration and Development1876-38042015-12-01426768777Features and origin of natural gas in the Sinian–Cambrian of central Sichuan paleo-uplift, Sichuan Basin, SW ChinaGuoqi WEI0Zengye XIE1Jiarong SONG2Wei YANG3Zhihong WANG4Jian LI5Dongliang WANG6Zhisheng LI7Wuren XIE8Langfang Branch of PetroChina Research Institute of Petroleum Exploration & Development, Langfang 065007, China; Key Laboratory of Gas Reservoir Formation and Development, CNPC, Langfang 065007, China; Corresponding authorLangfang Branch of PetroChina Research Institute of Petroleum Exploration & Development, Langfang 065007, China; Key Laboratory of Gas Reservoir Formation and Development, CNPC, Langfang 065007, ChinaPetroChina Southwest Oil and Gas Field Company, Chengdu 610000, ChinaLangfang Branch of PetroChina Research Institute of Petroleum Exploration & Development, Langfang 065007, China; Key Laboratory of Gas Reservoir Formation and Development, CNPC, Langfang 065007, ChinaLangfang Branch of PetroChina Research Institute of Petroleum Exploration & Development, Langfang 065007, China; Key Laboratory of Gas Reservoir Formation and Development, CNPC, Langfang 065007, ChinaLangfang Branch of PetroChina Research Institute of Petroleum Exploration & Development, Langfang 065007, China; Key Laboratory of Gas Reservoir Formation and Development, CNPC, Langfang 065007, ChinaLangfang Branch of PetroChina Research Institute of Petroleum Exploration & Development, Langfang 065007, China; Key Laboratory of Gas Reservoir Formation and Development, CNPC, Langfang 065007, ChinaLangfang Branch of PetroChina Research Institute of Petroleum Exploration & Development, Langfang 065007, China; Key Laboratory of Gas Reservoir Formation and Development, CNPC, Langfang 065007, ChinaLangfang Branch of PetroChina Research Institute of Petroleum Exploration & Development, Langfang 065007, ChinaBased on the new drilling data and field outcrop data of the Gaoshiti–Moxi area, the geochemical characteristics of the Sinian-Cambrian natural gas are studied and analyzed, including gas composition, isotope, light hydrocarbon, kerogen carbon isotope and reservoir bitumen biomarkers etc. The results show that: (1) The natural gases of the Sinian Dengying Formation and Cambrian Longwangmiao Formation, mainly composed of hydrocarbon gas, are typical dry gas. However, the natural gas of the Dengying Formation is characterized by higher dry coefficient, lower content of hydrocarbon gas and higher content of non-hydrocarbon gas. The main differences in non-hydrocarbon gases are the contents of N2, CO2, H2S and He, the small composition differences between the natural gas of Dengying Formation and that of Longwangmiao Formation are mainly caused by maturity differences of source rocks and H2S generated by reaction between sulfide mineral and hydrocarbons. (2) There are obvious differences in δ13C2 between the natural gases in Dengying Formation and Longwangmiao Formation, showing different parent materials of them. (3) There are large differences in δ2H between the natural gases of Dengying Formation and Longwangmiao Formation, showing the different water salinities of their source rock depositional environment. (4) The average kerogen carbon isotope values of the Lower Cambrian shale, Dengying Formation mudstone, Doushantuo Formation mudstone and Dengying Formation carbonates are −32.8‰, −31.9‰, −30.7‰ and −27.8‰ respectively. (5) The ratio of 4-methyl dibenzothiophene to 1-methyl dibenzothiophene of Dengying Formation bitumen is between that of Qiongzhusi Formation and Dengying Formation source rocks. It is believed that the Sinian-Cambrian natural gas in the Gaoshiti-Moxi area is mainly oil cracking gas, the Sinian natural gases come from the Sinian and Cambrian source rocks, and the Cambrian natural gases mainly come from Cambrian source rock. Key words: natural gas feature, gas genesis, Sinian, Cambrian, central Sichuan paleo-uplift, Sichuan Basinhttp://www.sciencedirect.com/science/article/pii/S1876380415300732 |