收稿日期: 2014-08-29
修回日期: 2014-09-29
网络出版日期: 2015-05-10
基金资助
国家科技重大专项“大型油气田及煤层气勘探开发”07项目(编号:2011ZX05007-002)资助.
Caprock Characteristics and Sealing Ability Evaluation of Sinian-Cambrian Gas Reservoirs in Gaoshiti-Moxi Area,Sichuan Basin
Received date: 2014-08-29
Revised date: 2014-09-29
Online published: 2015-05-10
四川盆地磨溪地区寒武系龙王庙组发现了迄今为止中国最大的碳酸盐岩整装特大型气田,新增天然气探明地质储量4 403.8×108m,而且在高石梯—磨溪地区已初步证实了震旦系、寒武系气藏规模超过万亿立方米。经历长期演化和多次构造运动的古老碳酸盐岩地层,为何气藏能够很好地保存下来,以及震旦系灯影组和寒武系龙王庙组气藏压力系数为何分别为常压和超压(压力系数为1.06~1.13和1.53~1.67)。通过宏观与微观、地质解剖与模拟实验相结合的方法,详细研究了气藏盖层特征及封闭能力。结果表明:研究区主要发育区域分布的寒武系泥页岩盖层、二叠系泥岩超压盖层和中下三叠统膏盐岩盖层|盖层岩石孔隙度以小于3%为主,渗透率主要为(0.001~0.02)×10-3μm,平均喉道半径为0.6~1.2μm,孔径多集中在400~500nm之间,饱和水突破压力多大于15MPa,扩散系数为1.03×10-10~2.36×10-7cm2/s。这些特征反映了盖层岩石具有一定的物性封闭能力,但诸如寒武系龙王庙组特大型整装超压气藏能够长期保存,是物性和超压共同封盖的结果。上述认识可以合理解释研究区常压、超压气藏的成因,同时对有效预测大气田的有利分布区域也有重要的指导意义。
张璐,谢增业,王志宏,展铭望,国建英,李亚红 . 四川盆地高石梯—磨溪地区震旦系—寒武系气藏盖层特征及封闭能力评价[J]. 天然气地球科学, 2015 , 26(5) : 796 -804 . DOI: 10.11764/j.issn.1672-1926.2015.05.0796
The reason why Sinian-Cambrian gas reservoirs in the Moxi area of the Sichuan Basin can survive well and why there is a great difference between pressure coefficient of Dengying reservoirs and Longwangmiao reservoirs have attracted more and more scientists.A detailed study of gas reservoir caprock characteristics and sealing ability by the combination of macroscopic and microscopic as well as geology dissection and simulation experiment has been carried out.Cambrian shale caprocks,Permian overpressure shale caprocks and Low-Middle Triassic gypsum caprocks are regionally distributed in the study area.The characteristics of caprocks are as follows,porosity is mainly less than 3%,permeability is (0.001-0.02)×10-3μm2,average throat radius ranges from 0.6μm to 1.2μm,pore size is mostly concentrated in 400-500nm,breakthrough pressure is more than 15MPa,and diffusion coefficient ranges from 1.03×10-10cm2/s to 2.36×10-7cm2/s.Caprocks have certain sealing ability,but the reason that Longwangmiao Gasfield can survive for a long history is the result of interaction of capillary sealing and overpressure sealing.Understandings above can be used to interpret formation reason of atmospheric and overpressure gas reservoirs in the study area reasonably.Meanwhile,it can be used for predicting favorable distribution of large gas field.
Key words: Natural gas reservoirs; Caprocks; Overpressure sealing; Sinian; Cambrian; Gaoshiti-Moxi area
[1]Liu Shugen,Qin Chuan,Jansa Lubomir,et al.Transformation of oil pools into gas pools as results of multiple tectonic events in Upper Sinian(Upper Neoproterozoic),deep part of Sichuan Basin,China[J].Energy Exploration& Exploitation,2011,29(6):649-697.
[2]Yao Jianjun,Chen Mengjin,Hua Aigang,et al.Formation of the gas reservoirs of the Leshan-Longnvsi Sinian Palaeo-uplift in central Sichuan[J].Petroleum Exploration and Development,2003,30(4):7-9.[姚建军,陈孟晋,华爱刚,等.川中乐山—龙女寺古隆起震旦系天然气成藏条件分析[J].石油勘探与开发,2003,30(4):7-9.]
[3]Xu Chunchun,Shen Ping,Yang Yueming,et al.Accumulation conditions and enrichment patterns of natural gas in the Lower Cambrian Longwangmiao Fm reservoirs of the Leshan-Longnvsi Paleohigh,Sichuan Basin[J].Natural Gas Industry,2014,34(3):1-7.[徐春春,沈平,杨跃明,等.乐山—龙女寺古隆起震旦系-下寒武统龙王庙组天然气成藏条件与富集规律[J].天然气工业,2014,34(3):1-7.]
[4]Wei Guoqi,Liu Delai,Zhang Lin,et al.The exploration region and natural gas accumulation in Sichuan Basin[J].Natural Gas Geoscience,2005,16(4):437-442.[魏国齐,刘德来,张林,等.四川盆地天然气分布规律与有利勘探领域[J].天然气地球化学,2005,16(4):437-442.]
[5]Jiang Hua,Wang Zecheng,Du Hongyu,et al.Tectonic evolution of the Leshan-Longnvsi Paleo-uplift and reservoir formation of Neoproterzoic Sinian gas[J].Natural Gas Geoscience,2014,25(2):192-200.[姜华,汪泽成,杜宏宇,等.乐山—龙女寺古隆起构造演化与新元古界震旦系天然气成藏[J].天然气地球科学,2014,25(2):192-200.]
[6]Wei Guoqi,Shen Ping,Yang Wei,et al.Formation conditions and exploration prospects of Sinian large gas fields,Sichuan Basin[J].Petroleum Exploration and Development,2013,40(2):129-138.[魏国齐,沈平,杨威,等.四川盆地震旦系大气田形成条件与勘探远景区[J].石油勘探与开发,2013,40(2):129-138.]
[7]Zheng Ping,Shi Yuhua,Zou Chunyan,et al.Natural gas sources in the Dengying and Longwangmiao Fms in the Gaoshiti-Maoxi area,Sichuan Basin[J].Natural Gas Industry,2014,34(3):50-54.[郑平,施雨华,邹春艳,等.高石梯—磨溪地区灯影组、龙王庙组天然气气源分析[J].天然气工业,2014,34(3):50-54.]
[8]Wei Guoqi,Xie Zengye,Bai Guilin,et al.Organic geochemical characteristics and origin of natural gas in Sinian-Lower Paleozoic reservoirs,Sichuan Basin[J].Natural Gas Industry,2014,34(3):44-49.[魏国齐,谢增业,白贵林,等.四川盆地震旦系—下古生界天然气地球化学特征及成因判识[J].天然气工业,2014,34(3):44-49.]
[9]Huang Wenming,Liu Shugen,Wang Guozhi,et al.Geological conditions and gas reservoir features in Lower Paleozoic in Sichuan Basin[J].Natural Gas Geoscience,2011,22(3):465-476.[黄文明,刘树根,王国芝,等.四川盆地下古生界油气地质条件及气藏特征[J].天然气地球科学,2011,22(3):465-476.]
[10]Wang Jinxing.Applications of a new method of confocal microsystem to geological studies[J].Geological Review,2004,50(2):215-517.[王金星.共聚焦显微扫描系统地新方法在地质科学研究中的应用[J].地质论评,2004,50(2):215-517.]
[11]Ying Fengxiang,Yang Shisheng,Zhang Min,et al.Application of laser scanning confocal microscope to the measurement of pore texture in reservoirs[J].Acta Sedimentologica Sinica,2002,20(1):75-79.[应凤祥,杨式升,张敏,等.激光扫描共聚焦显微镜研究储层孔隙结构[J].沉积学报,2002,20(1):75-79.]
[12]Wu Jie,Liu Chengdong,Zhang Shoupeng,et al.Application of micro-CT technology in petroleum geology[J].Jiangxi Science,2012,30(5):634-637.[JP3][吴洁,刘成东,张守鹏,等.显微CT技术在石油地质中的应用初探[J].江西科学,2012,30(5):634-637.]
[13]Zou Caineng,Zhu Rukai,Bai Bin,et al.First discovery of nano-pore throat in oil and gas reservoir in China and its scientific value[J].Acta Petrologica Sinica,2011,27(6):1857-1864.[邹才能,朱如凯,白斌,等.中国油气储层中纳米孔首次发现及其科学价值[J].岩石学报,2011,27(6):1857-1864.]
[14]Cheng Qiuquan,Chen Hongyu,Fan Ming,et al.Determinatin of the total pore texture of caprock[J].Petroleum Geology & Experiment,2006,28(6):604-608.[承秋泉,陈红宇,范明,等.盖层全孔隙结构测定方法[J].石油实验地质,2006,28(6):604-608.]
[15]Nelson P H.Pore-throat sizes in sandstones,tight sandstones,and shales[J].AAPG Bulletin,2009,93(3):329-340.
[16]Hu Guoyi,Wang Xiaobo,Wang Yifeng,et al.Cap rock characteristics of medium and large gas fields in China[J].Natural Gas Geoscience,2009,20(2):162-166.[胡国艺,王晓波,王义凤,等.中国大中型气田盖层特征[J].天然气地球科学,2009,20(2):162-166.]
[17]Deng Zuyou,Wang Shaochang,Jiang Zhenglong,et al.Breaking pressure of gas cap rocks[J].Oil & Gas geology,2000,21(2):136-138.[邓祖右,王少昌,姜正龙,等.天然气封盖层的突破压力[J].石油与天然气地质,2000,21(2):136-138.]
[18]Fu Guang,Wang Biao,Shi Jijian.Comprehensive quantitative evaluation method of sealing oil-gas ability of caprock and its application[J].Journal of Zhejiang University:Engineering Science,2014,48(1):174-180.[付广,王彪,史集建.盖层封盖油气能力综合定量评价方法及应用[J].浙江大学学报:工学版,2014,48(1):174-180.]
[19]Li Mingcheng.Basic principles of migration and hydrocarbon exploration[J].Earth Science,2004,29(4):379-383.[李明诚.油气运移基础理论与油气勘探[J].地球科学,2004,29(4):379-383.]
[20]Li Haiyan,Fu Guang,Peng Shimi.Quantitative study on the loss of natural gas diffusion in gas reservoirs[J].Petroleum Geology & Oilfield Development in Daqing,2001,20(6):25-27.[李海燕,付广,彭仕宓.气藏天然气扩散散失量的定量研究[J].大庆石油地质与开发,2001,20(6):25-27.]
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