摘要
塔里木盆地奥陶系油气勘探前期以塔北隆起、塔中凸起、塔中凸起斜坡区碳酸盐岩岩溶储层类型为主,并且发现了多个碳酸盐岩油气藏。但是塔北隆起与塔中凸起之间的北部坳陷却未获得油气发现,对储层发育机制及油气成藏模式认识不足制约了其油气勘探进程。为此,通过对该盆地北部坳陷走滑断裂的解释攻关,在识别走滑断裂的基础上,开展了断裂分层、分段研究,明确了走滑断裂对储层和油气藏形成的控制作用。研究结果表明:①北部坳陷走滑断裂活动较弱,双重滤波基础上提取振幅变化率属性,可以大幅度提高走滑断裂识别精度,并在北部坳陷识别出走滑断裂34条;②走滑断裂具有纵向分层的特征,形成寒武纪—奥陶纪以高角度线性走滑为主、志留纪—二叠纪以线性构造半花状构造为主、三叠纪—古近纪以雁列构造为主的3套断裂组合;③走滑断裂在平面上具有3分段特征,即形成于构造高点呈正花状的压扭段、明显地堑特征呈负花状的张扭段和断裂活动强度最弱的平移段;④走滑断裂控储控藏特征明显,平面上油气藏主要沿断裂带呈条带状分布,纵向上油气沿断裂带呈多层段分布,形成了9种油气藏模式。结论认为,基于叠后地震资料解释性处理的走滑断裂综合刻画技术实现了对弱走滑断裂的精细解释;上述9种油气藏模式有效地指导了该盆地北部坳陷的油气勘探部署,实现了该区油气的高效开发。
In the early exploration stage of Ordovician oil and gas in the Tarim Basin,carbonate karst reservoirs in Tabei uplift,Tazhong uplift and the slope of Tazhong uplift are dominant and a great number of carbonate oil and gas reservoirs are discovered.In the northern depression between the Tabei uplift and the Tazhong uplift,however,no oil and gas has been discovered and oil and gas exploration progress is restricted because its reservoir development mechanisms and hydrocarbon accumulation patterns are not understood sufficiently.After identifying the strike-slip faults by researching the interpretation on the strike-slip faults in the northern depression of the Tarim Basin,this paper studies the faults by layers and segments and then clarifies the control effect of strike-slip faults on reservoirs and hydrocarbon accumulation.And the following research results were obtained.First,the strike-slip fault activity in the northern depression is weaker.The accuracy of strike-slip fault identification can be greatly improved by extracting the attribute of amplitude change rate based on double filtering,and 34 strike-slip faults are identified in the northern depression.Second,strike-slip faults have the characteristics of vertical stratification,and there are three sets of fault combinations that are dominated by high-angle linear strike-slip in Cambrian to Ordovician,linear semi-flower-like structure in Silurian to Permian,and en-echelon structure in Triassic to Paleogene.Third,strikeslip faults present the characteristics of three segments on plane,i.e.,the compression and torsion segment of positive flower shape at the structural high,the tension and torsion segment of negative flower shape with obvious graben characteristics,and the translation segment with the weakest fault activity intensity.Fourth,the reservoirs and hydrocarbon accumulation are controlled by strike-slip faults obviously.The oil and gas reservoirs are mainly distributed along the fault belt on plane and oil and gas are distributed in multiple sections along faults in the vertical direction.Thus,there are 9 hydrocarbon accumulation patterns.In conclusion,the fine interpretation of weak strikeslip faults can be realized by virtue of the comprehensive description technology of strike-slip faults based on the interpretive processing of post-stack seismic data.What’s more,these 9 reservoir accumulation patterns effectively guide the exploration deployment in the northern depression of the Tarim Basin and realize the efficient oil and gas development in this area.
作者
汪如军
王轩
邓兴梁
张银涛
袁敬一
谢舟
李婷
罗枭
马小平
WANG Rujun;WANG Xuan;DENG Xingliang;ZHANG Yintao;YUAN Jingyi;XIE Zhou;LI Ting;LUO Xiao;MA Xiaoping(PetroChina Tarim Oilfield Company,Korla,Xinjiang 841000,China)
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2021年第3期10-20,共11页
Natural Gas Industry
基金
中国石油天然气股份有限公司重大科技专项“缝洞型碳酸盐岩油气藏效益开发关键技术研究与应用”(编号:2018E-1806)。
关键词
塔里木盆地北部坳陷
奥陶系
碳酸盐岩
走滑断裂
储集层
油气藏形成
控制作用
Northern depression of the Tarim Basin,Ordovician
Carbonate rock
Strike-slip fault,Reservoir
Hydrocarbon accumulation
Control effect
