伸展构造与反转构造对油气分布的控制作用--以松辽盆地东南隆起区为例

Control Effects of Spreading Structure and Reversal Structure on Hydrocarbon Distribution —An example from Dongnan uplift in Songliao basin

松辽盆地是大型中新生代具有"断"、"坳"双重结构的复合型沉积盆地,在构造演化史中表现为早期断陷、中期拗陷、晚期反转的演化特征。东南隆起区是松辽盆地的一级构造单元,发育了大量的伸展构造、反转构造,它们对油气的聚集、分布具有较强的控制作用。但是,由于伸展构造和反转构造形成的时期和发育的层位不同,对油气成藏的控制作用也不尽相同。伸展构造主要控制原生油气藏;而在深凹带范围内的反转构造主要控制次生油气藏,在斜坡带范围内的反转构造主要控制原生油气藏。

Songliao basin is a large-scale complex sedimentary basin of Mesozoic and Cenozoic with fault depressions and depressions. It features three structural evolution stages, showing fault depression at early stage, depression at middle stage, reversal structure at late one. Dongnan uplift is the Class-I tectonic unit in Songliao basin, in which there are lots of spreading structures and reversal structures. They play good control parts to the hydrocarbon accumulation and distribution here. But different stages of formation and different horizons of development for the spreading structures and reversal structures result in different control effects of them on hydrocarbon accumulation in it. The spreading structures mainly control the primary hydrocarbon reservoirs, while the reversal structures mainly control the secondary reservoirs in deep sag and the primary ones in slope area.