四川盆地东部海相下组合油气勘探领域与有利勘探方向

doi:10.19657/j.geoscience.1000-8527.2021.041

摘要/Abstract

摘要：

四川盆地是一个大型叠合含油气盆地,经历了多期伸展-聚敛旋回,资源潜力巨大。近年来,盆地中部下组合天然气勘探在震旦系灯影组和下寒武统龙王庙组获得重大突破,但盆地东部尚未获得实质性进展,有利勘探方向尚待明确。以构造-沉积演化分析为基础,将盆地东部及邻区海相下组合划分为伸展分异台地(震旦纪至早寒武世沧浪铺期)、稳定统一台地(早寒武世龙王庙期至中奥陶世宝塔期)和挤压前陆坳陷(晚奥陶世至志留纪)三个演化阶段;根据油气成藏要素和运聚特征,划分出寒武系盐下碳酸盐岩、寒武系盐上碳酸盐岩和志留系致密碎屑岩等三个油气勘探领域,不同勘探领域制约油气成藏和富集的关键因素差异较大;指出了川东南震旦系灯影组四段台缘带、川东寒武系洗象池群碳酸盐岩浅滩和志留系小河坝组大型三角洲砂体等,为盆地东部海相下组合的有利勘探方向,同时明确了重点突破地区。

关键词: 勘探领域, 有利勘探方向, 沉积-构造演化, 四川盆地东部

Abstract:

Sichuan Basin is a large superimposed petroliferous basin with great resource potential, which has experienced multi-stage extensional-compressional cycle. Few substantial gas exploration discoveries have been obtained so far in eastern Sichuan Basin while a series of natural gas exploration discoveries have been obtained in Dengying formation of the Upper Sinian system and Longwangmiao Formation of the Lower Cambrian system in recent years in the middle basin. By analysis of tectonic and sedimentary evolution, three evolutionary stages were built up from the Sinian period to the Silurian period in the eastern Sichuan basin and its adjacent areas: (1) extensional differentiation platform stage (from Sinian period to the Canglangpu phase of Early Cambrian period), (2) stable unified platform stage (from the Longwangmiao phase of Early Cambrian period to the Baota phase of the Middle Ordovician period), and (3) compressional foreland depression stage (Late Ordovician period to Silurian period). According to the comprehensive analysis of petroleum geological elements and the characteristics of hydrocarbon migration and accumulation, three hydrocarbon exploration domains are recognized, which are (1) pre-salt carbonate exploration domain (Sinian system to Gaotai Formation of the Middle Cambrian system), (2) post-salt carbonate exploration domain (Xixiangchi group of Middle-Upper Cambrian system to Baota Formation-Linxiang Formation of Middle-Upper Ordovician), and (3) tight clastic rock exploration domain (Upper Ordovician to Silurian system) from lower to upper, respectively. There exists major differences in the aspects of petroleum geological elements, characteristics of migration and accumulation of hydrocarbon, and main controlling factors, and therefore the key constraints of petroleum exploration are different in different exploration domains. By systematic evaluation of the exploration domains, it is pointed out that the carbonate platform marginal zone of the fourth member of the Dengying Formation in southeastern Sichuan basin, the carbonate shallow bank of the Cambrian Xixiangchi Group, and the large delta sand body of the Xiaoheba Formation of the Silurian system, etc. are favorable exploration directions and key breakthrough areas in the eastern Sichuan Basin.

Key words: exploration domain, favorable exploration direction, sedimento-tectonic evolution, eastern Sichuan Basin

中图分类号:

TE132

孙自明, 张荣强, 孙炜, 郝运轻, 卞昌蓉. 四川盆地东部海相下组合油气勘探领域与有利勘探方向[J]. 现代地质, 2021, 35(03): 798-806.

SUN Ziming, ZHANG Rongqiang, SUN Wei, HAO Yunqing, BIAN Changrong. Petroleum Exploration Domains and Favorable Directions of the Lower Marine Assemblage in Eastern Sichuan Basin[J]. Geoscience, 2021, 35(03): 798-806.

图/表 6

图1 四川盆地东部海相下组合构造-沉积演化阶段

Fig.1 Schematic sections illustrating the tectonic-sedimentary evolutionary stages of the Lower Marine Assemblage in eastern Sichuan Basin

图2 四川盆地东部海相下组合油气勘探领域 Ⅰ.盐下碳酸盐岩勘探领域;Ⅱ.盐上碳酸盐岩勘探领域;Ⅲ.致密碎屑岩勘探领域;1.变质岩;2.砂岩;3.粉砂岩;4.泥质粉砂岩;5.泥岩;6.白云岩;7.泥质白云岩;8.膏质白云岩;9.藻白云岩;10.鲕状白云岩;11.砂屑白云岩;12.灰岩;13.鲕粒灰岩;14.砂屑灰岩;15.生屑灰岩;16.膏盐岩

Fig.2 Petroleum exploration domains of the Lower Marine Assemblage in eastern Sichuan Basin

图3 四川盆地东部海相下组合油气成藏模式 1.油气运移方向;2.预测气藏;3.储层;4.膏盐岩;5.烃源岩;6.砂泥岩;7.碳酸盐岩。C-T.石炭系-三叠系;S.志留系;O.奥陶系;∈2+3X.洗象池群;∈2g.高台组;∈1q-∈1l.筇竹寺组-龙王庙组;Z2dn.灯影组;Z1d.陡山沱组;①灯影组二段气藏;②灯影组四段气藏;③下寒武统龙王庙组气藏;④中上寒武统洗象池群气藏;⑤中奥陶统宝塔组气藏;⑥志留系小河坝组气藏

Fig.3 Comprehensive pattern of migration and accumulation of hydrocarbon of the Lower Marine Assemblage in eastern Sichuan Basin

图4 四川盆地东南部地震地质解释剖面(灯影组二段顶部拉平,剖面位置见图5中的A-A’)

Fig.4 Interpreted seismic section in the eastern Sichuan Basin(flattened along the top of the second member of Dengying Formation,for location, see the A-A’ inFig.5)

图5 四川盆地东部海相下组合有利勘探地区有利勘探地区:Ⅰ.川东南灯影组台缘带有利勘探区;Ⅱ.中上寒武统洗象池群台内滩有利勘探区;Ⅲ.志留系石牛栏组台地边缘带有利勘探区;Ⅳ.志留系小河坝组三角洲有利勘探区;①永页7井;②永川

Fig.5 Favorable exploration areas for hydrocarbon of the Lower Marine Assemblage in eastern Sichuan basin

图6 四川盆地东部东山构造气藏成藏剖面(剖面位置见图5中的B-B') 1.断层;2.油气运移方向;3.气藏;4.中寒武统高台组膏盐岩;5.上奥陶统—下志留统烃源岩;T3-K.上三叠统—白垩系;T1+2.中下三叠统;P.二叠系;O3-S.上奥陶统—志留系;O1+2.中下奥陶统;∈2+3X中上寒武统洗象池群;∈2g.中寒武统高台组;Z-∈1.震旦系—下寒武统

Fig.6 Section showing natural gas migration and accumulation of the Dongshan anticlinal structure in eastern Sichuan basin(for location, see the B-B' in Fig.5)

参考文献 25

[1]	邹才能, 杜金虎, 徐春春, 等. 四川盆地震旦系-寒武系特大型气田形成分布、资源潜力及勘探发现[J]. 石油勘探与开发, 2014, 41(3): 278-293.
[2]	魏国齐, 杨威, 谢武仁, 等. 四川盆地震旦系-寒武系大气田形成条件、成藏模式与勘探方向[J]. 天然气地球科学, 2015, 26(5): 785-795.
[3]	赵路子, 汪泽成, 杨雨, 等. 四川盆地蓬探1井灯影组灯二段油气勘探重大发现及意义[J]. 中国石油勘探, 2020, 25(3): 1-12.
[4]	石书缘, 王铜山, 刘伟, 等. 四川盆地寒武系洗象池组储层特征及天然气勘探潜力[J]. 天然气地球科学, 2020, 31(6): 773-785.
[5]	李文正, 周进高, 张建勇, 等. 四川盆地洗象池组储集层的主控因素与有利区分布[J]. 天然气工业, 2016, 36(1): 52-60.
[6]	黄文明, 刘树根, 马文辛, 等. 四川盆地奥陶系油气勘探前景[J]. 石油与天然气地质, 2011, 32(3): 462-473.
[7]	陈宗清. 论四川盆地奥陶系天然气勘探[J]. 天然气工业, 2010, 30(1): 23-30.
[8]	汪泽成, 赵文智, 胡素云, 等. 克拉通盆地构造分异对大油气田形成的控制作用——以四川盆地震旦系-三叠系为例[J]. 天然气工业, 2017, 37(1): 9-23.
[9]	杨跃明, 文龙, 罗冰, 等. 四川盆地达州—开江古隆起沉积构造演化及油气成藏条件分析[J]. 天然气工业, 2016, 36(8): 1-10.
[10]	李伟, 刘静江, 邓胜徽, 等. 四川盆地及邻区震旦纪末-寒武纪早期构造运动性质与作用[J]. 石油学报, 2015, 36(5): 546-556.
[11]	魏国齐, 杨威, 杜金虎, 等. 四川盆地震旦纪-早寒武世克拉通内裂陷地质特征[J]. 天然气工业, 2015, 35(1): 24-35.
[12]	李智武, 冉波, 肖斌, 等. 四川盆地北缘震旦纪-早寒武世隆-坳格局及其油气勘探意义[J]. 地学前缘, 2019, 26(1): 59-85.
[13]	曾富英, 杨威, 孙爱, 等. 四川盆地川中地区震旦系灯影组台地边缘相带地震识别及其分段特征[J]. 石油与天然气质, 2017, 38(6): 1079-1086.
[14]	周进高, 张建勇, 邓红婴, 等. 四川盆地震旦系灯影组岩相古地理与沉积模式[J]. 天然气工业, 2017, 37(1): 24-31.
[15]	谷志东, 李宗银, 袁苗, 等. 四川盆地及其周缘晚震旦世-早寒武世早期区域抬升运动对岩溶储层发育的影响[J]. 天然工业, 2014, 34(8): 37-45.
[16]	单秀琴, 张静, 张宝民, 等. 四川盆地震旦系灯影组白云岩岩溶储层特征及溶蚀作用证据[J]. 石油学报, 2016, 37(1): 17-29.
[17]	邓大飞, 梅廉夫, 沈传波, 等. 江南-雪峰隆起北缘海相油气富集主控因素和破坏机制[J]. 吉林大学学报(地球科学版), 2014, 44(5): 1466-1477.
[18]	谷志东, 殷积峰, 袁苗, 等. 四川盆地东部深层盐下震旦系-寒武系天然气成藏条件与勘探方向[J]. 石油勘探与开发, 2015, 42(2): 137-149.
[19]	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.
[20]	陈娅娜, 张建勇, 李文正, 等. 四川盆地寒武系龙王庙组岩相古地理特征及储层成因与分布[J]. 海相油气地质, 2020, 25(2): 171-180.
[21]	谷明峰, 李文正, 邹倩, 等. 四川盆地寒武系洗象池组岩相古地理及储层特征[J]. 海相油气地质, 2020, 25(2): 162-170.
[22]	刘伟, 洪海涛, 徐安娜, 等. 四川盆地奥陶系岩相古地理与勘探潜力[J]. 海相油气地质, 2017, 22(4): 1-10.
[23]	李皎, 何登发, 梅庆华. 四川盆地及邻区奥陶纪构造-沉积环境与原型盆地演化[J]. 石油学报, 2015, 36(4): 427-445.
[24]	张海全, 许效松, 刘伟, 等. 中上扬子地区晚奥陶世-早志留世岩相古地理演化与黑色页岩的关系[J]. 沉积与特提斯地质, 2013, 33(2): 17-24.
[25]	郭英海, 李壮福, 李大华, 等. 四川地区早志留世岩相古地理[J]. 古地理学报, 2004, 6(1): 20-29.