吉尔嘎朗图凹陷宝饶断层的构造特征及其控油作用

宝饶构造带位于二连盆地吉尔嘎朗图凹陷中部,是凹陷的主力含油构造带。宝饶断层是控制该构造带油气纵、横向分布的决定性因素。地震剖面追踪解释显示,宝饶断层顺走向断面形态由平面式到铲状最后到坡坪式变化,上盘在反向调节断层作用下形成铲式扇正断层连锁系统,下盘在地层掀斜作用下形成一个大型鼻状构造。该断层形成于腾一段沉积早期,主要活动期为腾一段、腾二段沉积期,赛汉塔拉组沉积以后,由于区域挤压发生了正反转,第三系沉积早期,再次活动,多期的活动造成了宝饶断层断面形态的多样性。宝饶断层控制了宝饶构造带的油气运移与聚集,断层活动期与油气运移期的匹配是其控油的前提,断层两盘岩性配置关系是其控油的基础,断面所受的应力状态是其控油的关键因素。

Structural Character of Baorao Fault in Jiergalangtu Depression and Its Hydrocarbon - contrclling Function

Baorao tectonic zone lies in the middle of Jiergalangtu depression in Erlian basin and is the main tectonic zone containing oil and gas.Baorao normal fault in the decisive factor to control hydrocarbon vertical and horizontal distribution in this zone.By the earthquake sections tracking and explaining,Baorao fault varies from the planar normal fault to the listric normal fault,and finally to the ramp-flat normal fault along the fault strike.Its upper wall formed the listric normal fault linked system with the reversal adjustment faulting,and lower wall formed a large fault nose under the stratum tilting.This fault emerged during the earlier period of early Cretaceous and its main movement period is the depositing period of Tenggeer formation.After Saihantala formation sedimentation,Baorao fault was reversed to form the positive inversion structure because of the regional compression,and early Tertiary,it moved again.Movement for many times leads to produce many kinds of Baorao fault plane.Baorao fault controlled the hydrocarbon migration and accumulation of Baorao zone.It is the premise for fault controlling oil and gas that periods match between fault movement and hydrocarbon migration;it is the bas is for fault controlling oil and gas that lithologic deployment between upper wall and lower wall,and the stress state of the fault plane in the crucial factor for Baorao fault controlling hydrocarbon.