Characteristics of the Individual Carbon Isotope of Natural Gas from Suligemiao and Jingbian Gas Fields in Ordos Basin
-
摘要: 苏里格庙上古生界砂岩气藏天然气重烃含量高,干燥系数低,为湿气;靖边奥陶系风化壳气藏天然气重烃含量低,干燥系数高,属干气。苏里格庙天然气的正构烷烃碳同位素具有δ13 C1<δ13 C3 <δ13 C2 <δ13 C4的规律,靖边天然气具有δ13 C1<δ13 C2 <δ13 C3 的规律。二者高碳数烷烃的同位素差别较大,尤其是苏里格庙的乙烷碳同位素比靖边平均重 3.6‰。根据天然气单体碳同位素及其含量变化,苏里格庙天然气属煤成气,靖边天然气属煤成气与油型气的混合气。苏里格庙和靖边天然气中均含少量CO2 气,其碳同位素表明苏里格庙除苏 5井为无机CO2 气外,均为有机CO2 气;靖边林 1、林 5井为无机CO2 气,陕参 1井为有机CO2 气。结合烷烃气和CO2 气,苏里格庙天然气可以分为含有机CO2 煤成气和含无机CO2 煤成气。碳同位素比值与Ro 关系分析认为,苏里格庙的天然气成熟度处于成熟到高成熟阶段,其相应气源岩的平均Ro 为 1.2 9%～ 1.39%,这一结果与该区二叠系煤岩的成熟度符合较好。Abstract: Natural gas from the gas pool reservoired in Upper Paleozoic sandstone of Sulige miao area is wet gas that is characterized by high content of heavy hydrocarbon and low dry coefficient;otherwise,natural gas from Ordovician weathering crust g as pool in Jingbian area belongs to dry gas for its low content of heavy hydroar bon and high dry coefficient.The istotpic composition of Suligemiao gas has the tendency of δ13 C1<δ13 C4, but Ji ngbian gas tends to be δ13 C1<δ13 C3. The isotopi c difference of heavy carbon alkane is much larger between Suligemiao and Jinybi an natural gas.Particularly,the carbon isotope of ethane of Suligemiao gas is hi gher than that of Jingbian.The difference is equal to 3.6%.According to individu al carbon isotopes and compositions of natural gas,it can be seen that the Sulig emiao Permian gas is coalbed gas,and the Jingbian Ordovician gas is gaseous mixt ure.Average R o of Suligemiao gas and its source rock is equal to 1.29%～1.39% according to CH 4 isotope values, which is consistent with R o of the Permian rock.A little of CO 2 content is found in Suligemiao and Jing b ian natural gas.In terms of the carbon isotope values,it is believed that inorga nic CO 2 exists in well Su5 in Suligemiao and well Lin1, Lin5 in Jingbian.The rest are all organic CO 2.In combination with hydrocarbon gas and CO 2,the n atural gas in Suligemiao could be divided into coal-formed gas with organic CO 2 and inorganic CO 2.The maturity of coal-formed gas in Suligemiao reaches middle to high stage and the corresponding R o is 1.29%～ 1.39%,which i s in line with the maturity in Permian coal.
-
Key words:
- individual carbon isotope /
- natural gas /
- genetic types /
- Suligemiao
-
[1] 蒋助生, 胡国艺, 李志生等. 鄂尔多斯盆地古生界气源对比新探索[J]. 沉积学报, 1999, 17(增刊): 221～223[Jiang Zhusheng,Hu Guoyi,Li Zhisheng,et al.The novel approach of the correlation between Paleoozoic natural gas and source rock in Ordos Basin[J].Acta Sedimentologica Sinica,1999,17(Supp.):221～223] [2] 陈安定. 陕甘宁盆地中部气田奥陶系天然气的成因及运移[J]. 石油学报, 1994, 15(2): 1～10[Chen Anding.Origin and migration of natural gas in Ordovician reservoir in Shan-Gang-Ning Basin Central Gas Field[J].Acta Petroloei Sinica,1994,15(2):1～10] [3] 黄第藩, 熊传武, 杨俊杰等. 鄂尔多斯盆地中部天然气气源判识和天然气成因类型[J]. 天然气工业, 1996, 16(6):1～5[Huang Difang,Xong Chuangwu and Yang Junjie.Source identifications and genetic types of natural gas in Ordos Basin Central Gas Field[J].Natural Gas Industry,1996,16(6):1～5] [4] 张世亚. 鄂尔多斯盆地天然气起源及勘探方向[J]. 天然气工业, 1994, 14(3): 1～4[Zhang Shiya.Natural gas source and exploration direction in Ordos Basin[J].Natural Gas Industry,1994,14(3):1～4] [5] 夏新宇, 赵林, 戴金星等. 鄂尔多斯盆地中部气田奥陶系风化壳气藏天然气来源及混源比计算[J]. 沉积学报, 1998, 16(3): 75～78[Xia Xinyu,Zhao Lin,Dai Jingxing,et al.Gas sources and mixing ratio of Ordovician weathering crust reservior of central gas field in Ordos Basin[J].Acta Sedimentologica Sinica,1998,16(3):75～78] [6] 秦建中, 贾蓉芬, 郭爱明等. 华北地区煤系烃源岩油气生成、运移、评价[M]. 北京: 科学技术出版社, 2000[Qin Jianzhong,Jia Rongfeng,Guo Aiming,et al.Generation,migration and evaluation on hydrocarbon in bearing-coal source rock,Huabei Area[M].Beijing: Science & Technology Press,2000] [7] 戴金星, 裴锡古, 戚厚发.中国天然气地质学[M]. 北京: 石油工业出版社, 1992[Dai Jinxing,Pei Xigu,and Qi Houfa.Geology of natural gas in China[M].Beijing:Petroleum Industry Press,1992] [8] 刘文汇, 徐永昌. 天然气成因类型及判别标志[J]. 沉积学报, 1996, 14(1): 110～115[Liu Wenghui and Xu Yongchang.Genetic indicators for natural gases[J].Acta Sedimentologica Sinica,1996,14(1):110～115] [9] 刚文哲, 高岗, 郝石生等. 论乙烷碳同位素在天然气成因类型研究中的应用[J].石油实验地质, 1997, 19(2): 164～167[Gang Wenzhe,Gao Gang,Hao Shisheng,Zhu Lei.Carbon isotope of ethane in analysis of genetic types of natural gas[J].Experimental Petroleum Geology,1997,19(2):164～167] [10] Berner U, Faber E. Maturity related mixing model for methane, ethane, and propane, based on carbon isotopes[A]. Advances in Organic Geochemistry 1987[C]. Organic Geochemistry, 1998,13(1～3):67～72 -
点击查看大图
计量
- 文章访问数: 463
- HTML全文浏览量: 8
- PDF下载量: 421
- 被引次数: 0
下载:
