四川盆地震旦系威远—安岳拉张侵蚀槽特征及形成演化

石油勘探与开发

26 2015年2月PETROLEUM EXPLORATION AND DEVELOPMENT Vol.42 No.1 文章编号：1000-0747(2015)01-0026-08 DOI: 10.11698/PED.2015.01.03

四川盆地震旦系威远—安岳拉张侵蚀槽特征及形成演化

李忠权1,2，赖芳1,3，李应4，杭文艳2，洪海涛5，应丹琳5，

陈骁5，刘冉1,2，段新国1,2，彭戟1,2

（1. 成都理工大学油气藏地质及开发工程国家重点实验室；2. 成都理工大学国土资源部构造成矿成藏重点实验室；

3. 成都工业学院；

4. 密苏里科技大学；

5. 中国石油西南油气田分公司）

基金项目：国家自然科学重点基金（41030426）；国家自然基金主任基金（41340004）；国家重大专项

（2011ZX05004-005-01）；四川省省属高校科研创新团队项目（13TD0007）

摘要：基于沉积、构造综合分析，利用露头、钻井、测井及地震资料，研究四川盆地震旦系威远—安岳拉张侵蚀槽的平面、剖面特征，并根据地层、岩性、构造及区域演化等特征对震旦系进行剥蚀恢复，再现桐湾运动时期拉张侵蚀槽各阶段发育演化及其改造过程。威远—安岳拉张侵蚀槽沿蓬莱—安岳—荣昌一线呈北西向展布，具有东陡西缓的特征。

研究横跨拉张侵蚀槽中部的威远—龙女寺地震剖面发现，威远—安岳拉张侵蚀槽是震旦纪期间基底断裂多幕堑垒式活动导致灯影组地层差异抬升、差异侵蚀和差异溶蚀等多种地质过程综合作用的结果，其形成可分为早、中、晚3个阶段。通过剖面剥蚀恢复，定量测算了拉张侵蚀槽侵蚀、溶蚀量，最大可达600 m。图11参28

关键词：四川盆地；震旦系；威远—安岳；拉张侵蚀槽；形成演化

中图分类号：TE122 文献标识码：A

Formation and evolution of Weiyuan-Anyue extension-erosion groove in

Sinian system, Sichuan Basin

Li Zhongquan1,2, Lai Fang1,3, Li Ying4, Hang Wenyan2, Hong Haitao5, Ying Danlin5, Chen Xiao5,

Liu Ran1,2, Duan Xinguo1,2, Peng Ji1,2

(1. Chengdu University of Technology State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu

610059, China; 2. Chengdu University of Technology Key Laboratory of Tectonic Controls on Mineralization and

Hydrocarbon Accumulation, Ministry of Land and Resource, Chengdu 610059, China; 3. Chengdu Technological University, Chengdu 611730, China; 4. Missouri University of Science and Technology, Missouri 615401,

USA; 5. PetroChina Southwest Oil and Gas Field Company, Chengdu 610051, China)

Abstract:Based on comprehensive analysis of deposition and structure, the horizontal and vertical characteristics of the Weiyuan-Anyue erosion-extension groove have been studied using outcrop, drilling, well logging and seismic data. According to the strata, lithology, structure and regional evolution, the Sinian system before the erosion has been reconstructed to show the development and transformation of the erosion-extension groove in the Tongwan orogeny. The Weiyuan-Anyue extension-erosion groove is distributed along the Penglai-Anyue-Rongchang in NW direction, with the west area steeper than the east in groove.

According to the study of the Weiyuan-Longnüsi seismic profile across the middle area of erosion-extension groove, the formation of the Weiyuan-Anyue extension-erosion groove is the synthetic result of different geological processes from differential uplift, the denudation, erosion and dissolution in the Dengying Formation caused by multiple-phase episode grabon or horst movement of the Sinian basement fault. The formation of the Weiyuan-Anyue erosion-extension groove can be divided into three stages, and the erosion and dissolution can be calculated quantitatively by denudation recovery profile, its maximum can reach 600 m.

Key words:Sichuan Basin; Sinian; Weiyuan-Anyue; extension-erosion groove; formation and evolution

0 引言

近两年在四川盆地震旦系灯影组（Z2dn）油气勘探过程中发现川中威远、安岳之间灯影组四段（灯四段）、灯影组三段（灯三段）部分或完全缺失，寒武系筇竹寺组显著增厚。同时经钻井、二维和三维地震勘探证实，该区域发育一大型沟槽，其内充填了巨厚的下寒武统深水相黑色硅质页岩、黑灰色泥质白云岩、灰质页岩与黑色页岩等烃源岩[1]。寒武系烃源岩与沟槽两侧灯影组白云岩形成了优越的源储配置油气成藏系统（新生古储）[2]，勘探证实对震旦系灯影组油气聚集、成藏具有明显的控制作用。因此，明确威远—安岳沟槽

石油勘探与开发

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