二连盆地边界断层的生长模型及其对含油气系统形成的控制

Boundary fault propagation pattern and its application to the formation of petroleum systems in the Erlian basin.

断层连锁现象在裂谷盆地中十分普遍 ,断层连锁虽是短暂的过程 ,但该过程不仅改变了连锁前的沉积分布格局 ,同时对断陷的发育史存在控制作用。裂谷盆地半地堑边界正断层的生长可以划分为两种模式 :断层简单生长模式和断层生长连锁模式。根据对二连盆地典型断陷的构造、沉积发育和烃源岩分布特征等方面的研究 ,发现存在三种类型断陷 :阿北凹陷 ,受单一断层生长控制发育 ,形成一个含油气系统 ;赛汉塔拉凹陷 ,受多条断层生长控制发育 ,形成一个含油气系统 ;乌里亚斯太凹陷 ,受多条断层生长控制发育 ,形成多个含油气系统。因此 ,并不是所有断陷都仅发育一个独立的含油气系统 ,可能发育两个或多个含油气系统。断层连锁前的传递斜坡是砂砾岩体发育的重要部位 ,也是勘探地层 岩性圈闭油气藏的重要领域。

Fault linkage in rift basins is very common. The process of fault linkage is very short, but it changes the sedimentary patterns before and after linkage and controls the development of fault depressions. The propagation and growth of boundary faults can be divided into 2 types: simple fault propagation pattern and fault growth-linkage pattern. Based on the structural style, sedimentary patterns and distribution of active source rocks in the Erlian basin, 3 types of depression and petroleum system can be identified: Abei depression controlled by one boundary fault forms petroleum system; Saihantala depression controlled by several boundary fault segments forms a petroleum system; and Wuliyasitai depression controlled by multiple boundary fault segments forms several petroleum systems. Therefore, not all fault depressions develop one independent petroleum system, sometimes they have two or more systems. The relay ramps between fault segments before linkage are the places where sandy conglomerate bodies deposited, and consequently, the frontier area for exploring for stratigraphic-lithologic fields.