松辽盆地“T2”断层系及青山口早期伸展裂陷

“Ｔ２”地震反射层面是泉头组顶面或青山口组底面，“Ｔ２”反射结构是指其同相轴不连续且错迭的现象。这种反射结构不是前积成因，而是“Ｔ２”断层系的反映。“Ｔ２”断层为的形成是青山口期ＮＥＥ－ＳＷＷ向伸展裂陷过程中，先存ＮＮＥ向断裂产生扭张运动，导致上覆层变形有的结果。

T_2" FAULTS SYSTEM AND EARLY QINGSHANKOU STRETCHED RIFITING IN SONGLIAO BASIN.

T2" seismic reflector represents the top of Quantou formation or the bottom of Qingshankou formation."T2" reflection structure is the discontinuous, dislocated and overlapped phenomena of "T2" event. The reflection structure is not considered to be the response of progradtion but as that of the "T2" fault system.The "T2" faults are growth faults, with a small scale and steeper dip, trending to NNW mostly which occur predominantly in the sites of basement fault structural bend zone and basement uplift. The formation of "T2" fault system is due to the deformation of overlaying formation caused by shearing tensile movement of the pre-existing NNE trending faults during the NEE-SWW trending stretched rifting of Qingshankou age.