断裂在贝尔凹陷油运聚成藏中作用

为研究断裂在贝尔凹陷油运聚成藏中的作用,通过油藏解剖分析油藏与断裂之间空间匹配关系.结果表明:贝尔凹陷油藏从基岩至大磨拐河组皆有分布,主要为断层油藏和受断层控制的基岩潜山油藏,平面上主要分布在与断裂活动有关的凹间隆、洼中隆、斜坡断阶带上.贝尔凹陷主要发育早期伸展、中期走滑和晚期反转(或长期发育)3种类型断裂,断裂对贝尔凹陷油运聚成藏主要起3方面控制作用:(1)长期发育断裂为南一段源岩生成油向大磨拐河组运移提供输导通道,早期伸展断裂错断使源储侧接,南一段源岩生成的油向基岩、铜钵庙组和南屯组储层侧向运移;(2)早期伸展断裂为基岩、铜钵庙组和南屯组油聚集提供遮挡条件;(3)断裂活动为不同层位油聚集提供构造背景.在贝尔凹陷断裂控藏有早期伸展断裂遮挡油聚集成藏和长期发育断裂输导油聚集成藏2种模式.

Effects of faults on oil migration and accumulation in Beier depression

By anatomy of oil reservoirs and research on space matching relations between oil reservoirs and fault,it is considered that oil reservoirs which are main fault reservoirs and basement buried hill oil reservoirs controlled by faults distribute from the bedrock to K1d,on plane,they distribute at the rise in delves,the rise in low-lying lands and fault step zone which are related to the fault.There are three types of fault mainly developed in Beier depression: extensional faults formed in the early period,strike-slip faults formed in the middle period and faults formed in long term,they are 3 controlling of faults to oil migration and accumulation: firstly,faults formed in long term supply migration transporting passways for oil from K1n1 source rock to K1d,and faults formed in the early period make source rock and reservoir touch,oil from K1n1 source rock migrates laterally to bedrock,K1t and K1n reservoir;secondly,faults formed in the early period provide sealing for oil accumulation in bedrock,K1t and K1n;lastly,the action of faults provide Tectonic setting for oil accumulation in different oil layers.There are two fault controlling oil accumulation models: oil accumulation model of extensional faults in the early period sealing and oil accumulation model of fault in long term transporting.