摘要
上扬子克拉通震旦系—寒武系油气资源丰富,其中在德阳—安岳裂陷东侧,台缘带勘探取得了重大突破,其油气主要赋存于规模碳酸盐岩丘滩体中,规模丘滩储集体的预测是勘探的关键。在前人研究的基础上,应用露头、岩心、测井和地震等资料,对上扬子克拉通的构造演化和岩相古地理进行了系统研究,提出了3点新认识。(1)上扬子克拉通东部发育一个近菱形的陆架镶边台地,称之为“安岳—奉节台地”;台地的西边界对应德阳—安岳裂陷的东边界,北边界即上扬子克拉通的北边界,东边界对应城口—鄂西裂陷的西边界,南边界对应湘中南大陆边缘海的北边界;台地发育在晚震旦世灯影组一段+灯影组二段沉积期—早寒武世龙王庙组沉积期,尤其在灯影组四段沉积期最为发育。(2)安岳—奉节台地发育台坪相、台地边缘相和斜坡—盆地相;台坪相发育于台地内,主要包括台内滩、云坪和潟湖等亚相;台地边缘相主要发育台地边缘丘、滩亚相;台地外的斜坡—盆地相以发育泥页岩为主;规模丘滩体沿台地边缘呈环带状分布,主要集中在灯影组二段、灯影组四段、沧浪铺组下段和龙王庙组。(3)安岳—奉节台地控制了四川盆地震旦系—寒武系大气田的形成与分布;台地边缘的高能相带控制了规模储层,台地周围的斜坡—盆地相内发育优质烃源岩,这种有利的源-储成藏组合形成了大型地层-岩性圈闭群,控制了油气规模聚集区。安岳—奉节台地可优选出3类6个有利勘探区块,总资源潜力为(6.5~9.0)×1012m3,这为下一步勘探部署提供了依据。研究成果丰富了碳酸盐岩沉积学和成储成藏地质理论,对勘探部署有重要意义。
The Sinian-Cambrian oil and gas resources are rich in the Upper Yangtze craton.In the east side of Deyang-Anyue rift,a great breakthrough has been made in the exploration of platform margin belt,where oil and gas mainly occur in large-scale carbonate mound-shoal complex,so the prediction of large-scale mound-shoal reservoir is the key to hydrocarbon exploration.On the basis of previous studies,the tectonic evolution and lithofacies palaeogeography of the Upper Yangtze craton have been systematically studied using outcrop,core,logging and seismic data,and three new understandings are put forward as below.(1)A nearly rhombic shelf-rimmed platform called“Anyue-Fengjie platform”developed in the east of the Upper Yangtze craton.The western boundary of the platform was the eastern boundary of the Deyang-Anyue rift,the northern boundary was the northern boundary of the Upper Yangtze craton,the eastern boundary was the western boundary of the rift from Chengkou to Western Hubei,and the southern boundary was the northern boundary of the continental marginal sea in central and southern Hunan Province.The platform developed in the sedimentary period from the Member 1 and 2 of Late Sinian Dengying Formation to the Early Cambrian Longwangmiao Formation,especially in the period of the Member 4 of Dengying Formation.(2)Platform flat,platform margin and slope-basin facies develop in Anyue-Fengjie platform.Platform flat facies in the platform mainly include intra-platform shoal,dolomitic flat and lagoon subfacies.Platform margin facies mainly include mound and shoal subfacies.The slop-basin facies outside the platform are mainly mud shale.The large-scale mound-shoal complexes distributed in a ring-like pattern along the platform margin mainly occur in the Member 2 and 4 of Dengxiang Formation,the Lower Member of Canglangpu Formation,and the Longwangmiao Formation.(3)The Anyue-Fengjie platform controls the formation and distribution of Sinian-Cambrian large gas fields in Sichuan Basin.The reservoirs develope in the high energy
作者
魏国齐
贾承造
杨威
Wei Guoqi;Jia Chenzhao;Yang Wei(PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China)
出处
《石油学报》
EI
CAS
CSCD
北大核心
2023年第2期223-240,311,共19页
Acta Petrolei Sinica
基金
国家自然科学基金项目“环青藏高原盆山体系动力学与天然气富集机理(批准号U22B6002)”
中国石油天然气股份有限公司“十四五”前瞻性基础性科技重大项目(2021DJ0605)资助。
关键词
安岳—奉节陆架镶边台地
碳酸盐岩
震旦系—寒武系
油气勘探
台缘丘滩体
有利勘探区
Anyue-Fengjie shelf-rimmed platform
carbonate
Sinian-Cambrian
oil-gas exploration
platform margin mound-shoal complex
favorable exploration block
