ACCUMULATION PROCESS OF THE UPPER GAS ASSEMBLAGE ON THE SOUTHWEST MARGIN OF UPPER YANGTZE BASIN
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摘要:
通过对代表上扬子盆地西南缘上组合气藏特征的平落坝、白马庙和观音寺3个典型气藏进行解剖,明确了中侏罗统沙溪庙组天然气分布特征。结合输导体系、流体包裹体成藏期次和构造演化研究成果,分析了气藏成藏过程,总结其成藏模式,以期为有利勘探目标区的选择及评价提供地质依据。上扬子盆地西南缘沙溪庙组气藏以构造-岩性和岩性气藏为主,天然气主要分布在沙溪庙组Ⅰ、Ⅱ、Ⅲ段,主要聚集于构造高点。油气成藏时间集中在93~72 Ma,发生过至少2幕油气充注。燕山运动是气藏形成的主要时期,其形成的断层是沟通气源的主要通道;喜山运动是气藏天然气调整的主要时期,喜山期逆冲断层的活动及构造高点的迁移是天然气调整的主要原因。不同构造区域成藏具有差异性:西部褶皱带断-砂匹配、构造、砂体物性是主要控藏因素,构造高点、断层封闭性控制其含气丰度;东部斜坡带断-砂匹配、构造、封闭断层是主要控藏因素,构造高点、砂体物性控制其含气丰度。
Abstract:Three typical gas reservoirs, the Pingluoba, Baimamiao and Guanyinsi, selected from the upper gas reservoir assemblage on the southwest margin of the Upper Yangtze Basin, are studied for gas distribution in the Middle Jurassic Shaximiao Formation with the research results from gas transportation system, fluid inclusion accumulation period and tectonic evolution. The study has provided a solid geological basis for the determination and evaluation of favorable exploration target areas. The gas reservoirs, dominated by structural-lithologic and lithologic traps, are mainly accumulated in the structural highs of Sha I, Sha Ⅱ and Sha Ⅲ Members and deposited in the time span of 93-72 Ma, by two stages of hydrocarbon charging. Yanshan movement is the main period for the formation of gas reservoirs, active faults originated in the Yanshan movement provided channels connecting the source rocks and the gas accumulations. Himalayan movement is the main period for the adjustment of natural gas, the reverse fault activity and tectonic peak adjustment in the Himalayan movement led to the readjustment of gas reservoirs. The accumulation processes are different in different tectonic provinces. Fault-sand matching, structures and physical properties of sand bodies are the main controlling factors in the western fold belt, while structural high and fault sealing the main factors controlling the gas abundance; fault-sand matching, structures and sealing fault are the main controlling factors in the eastern slope belt, and the structural high and physical properties of sand bodies are the factors controlling the gas abundance.
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表 1 平落坝构造主要断层活动时间
Table 1. Activities of main faults in Pingluoba structure
断层名称 断开层位 活动时间 F1 J3p—T3x 燕山中幕(蓬莱镇沉积期) F2 J3p—T3x 燕山中幕(蓬莱镇沉积期) F3 J2sx—T3x 燕山中幕(沙溪庙沉积期) F4 K—T3x 燕山中—晚幕 -
[1] 宋金民,罗平,刘树根,等. 四川盆地西部震旦系灯影组沉积储层特征[J]. 成都理工大学学报(自然科学版),2018,45(1):27-44.
[2] 蔡开平,廖仕孟. 川西地区上三叠统轻烃的生成特征[J]. 石油学报,2002,23(1):35-39. doi: 10.3321/j.issn:0253-2697.2002.01.008
[3] 蔡开平,王应蓉,刘雪梅,等. 川西南部侏罗系油气垂向运移特征[J]. 西南石油学院学报,2000,22(4):1-5.
[4] 蔡开平,廖仕孟. 川西地区侏罗系气藏气源研究[J]. 天然气工业,2000,20(1):36-41. doi: 10.3321/j.issn:1000-0976.2000.01.009
[5] 陈林. 川西南部地区沙溪庙组储层特征及其控制因素研究[D]. 成都: 西南石油大学, 2015.
[6] 于冬冬,汤良杰,余一欣,等. 川西和川东北地区差异构造演化及其对陆相层系天然气成藏的影响[J]. 现代地质,2016,30(5):1085-1095. doi: 10.3969/j.issn.1000-8527.2016.05.013
[7] 张卫海,查明,曲江秀. 油气输导体系的类型及配置关系[J]. 新疆石油地质,2003,24(2):118-120,185. doi: 10.3969/j.issn.1001-3873.2003.02.008
[8] 刘景东,蒋有录,马国梁. 断面优势运移通道的有效性及其对油气的控制作用[J]. 特种油气藏,2011,18(3):47-50,137. doi: 10.3969/j.issn.1006-6535.2011.03.012
[9] 鲁兵,陈章明,关德范,等. 断面活动特征及其对油气的封闭作用[J]. 石油学报,1996,17(3):33-38. doi: 10.3321/j.issn:0253-2697.1996.03.005
[10] 吴文静,吴东胜. 川西坳陷东坡断裂优势运移通道预测[J]. 中国科技论文,2019,14(5):476-480,523. doi: 10.3969/j.issn.2095-2783.2019.05.002
[11] 罗晓容,雷裕红,张立宽,等. 油气运移输导层研究及量化表征方法[J]. 石油学报,2012,33(3):428-436. doi: 10.7623/syxb201203012
[12] KING P R. The connectivity and conductivity of overlapping sand bodies[C]//BULLER A T, BERG E, HJEMELAND O, et al. North Sea Oil & Gas Reservoirs-II, London: Graham and Trotman, 1990: 353-362.
[13] 马安来,张水昌,张大江,等. 油气成藏期研究新进展[J]. 石油与天然气地质,2005,26(3):271-276. doi: 10.3321/j.issn:0253-9985.2005.03.002
[14] 赵靖舟. 油气水界面追溯法与塔里木盆地海相油气成藏期分析[J]. 石油勘探与开发,2001,28(4):53-56. doi: 10.3321/j.issn:1000-0747.2001.04.016
[15] 刘可禹,BOURDET J,张宝收,等. 应用流体包裹体研究油气成藏:以塔中奥陶系储集层为例[J]. 石油勘探与开发,2013,40(2):171-180. doi: 10.11698/PED.2013.02.05
[16] 林小云,魏民生,丰勇,等. 四川盆地川西坳陷东坡沙溪庙组油气成藏关键时刻研究[J]. 石油实验地质,2017,39(1):50-57. doi: 10.11781/sysydz201701050
[17] 刘世豪,林小云,刘建. 济源凹陷中生界流体包裹体特征与油气成藏期次[J]. 海洋地质前沿,2020,36(4):55-60.
[18] 覃军, 蒋一鸣, 李宁, 等.东海陆架盆地西湖凹陷Y构造油气成藏过程及勘探启示[J].海洋地质与第四纪地质, 2019, 39(6): 159-168.
[19] 刘建, 谢睿, 徐敏, 等.东海西部台北坳陷中生界油气成藏模式研究[J].海洋地质与第四纪地质, 2019, 39(6): 150-158.
[20] 乔诚. 川西坳陷东坡沙溪庙组气藏气水分布特征及成藏过程研究[D]. 武汉: 长江大学, 2017.
[21] 袁红英. 川西坳陷东坡沙溪庙组成藏过程研究[D]. 武汉: 长江大学, 2017.
[22] 徐敏,刘建,林小云,等. 川西坳陷东坡沙溪庙组气藏成藏演化模式[J]. 现代地质,2018,32(5):953-962.