梨树断陷边界控陷断裂活动特征及油气地质意义

Active characteristics and petroleum geological significance of boundary fault controlled by Lishu Fault Depression

通过对梨树断陷连片三维的解释,重新认识边界控陷断裂桑树台断裂活动特征,取得以下三个新的认识:(1)桑树台断裂在火石岭时期是由三条北东向斜列的断层组成,控制着三个北东向次洼;(2)在断层的叠接处,火石岭组末期已经开始走滑,发现小宽断裂南和皮家东两条走滑断层,走滑距离分别是2. 5 km和1 km,这两条断层南段控制洼陷的沉积,北段直立走滑,这个时期的走滑主要是因为火石岭末期构造反转,挤压的环境下形成,小宽走滑断裂带一直可以延伸至桑树台断裂,扩大了勘探领域;(3)控陷的桑树台断裂在不同时期、不同部位活动强度存在明显差异,决定了不同层系勘探方向不同,沙河子组下一步勘探的有利区为桑树台断裂带的中段、南段,营城组下一步勘探的有利区为桑树台断裂带的中段、北段。

Through three-dimensional interpretation of Lishu Fault Depression,it was again recognized the active characteristics of Sangshutai Fault controlled by boundary.So three new understandings are as follows:1.in the Huoshiling period,the Sangshutai Fault was composed of three northeast diagonal faults which control three Northeast subsags;2.at the lap connection of the Sangshutai Fault,the strike-slip has been begun in the last stage of Huoshiling Formation,and it was found two strike-slip faults,Xiaokuan South and Pijia East,where the strike-slip distance is 2.5 km and 1km,respectively.The subsidence was controlled by the southern sections of the two faults.The slip of the northern segment was upright slippery mainly due to the tectonic inversion.The Xiaokuan strike-slip faults may extend all the way to the Sangshutai Fault so as to expand the exploration area;3.There is significant differences in the activity intensity of the Sangshutai Fault in different periods and parts,which determine the exploration directions of different strata.The favorable exploration area for the next step in Shahezi Formation is the middle and southern sections of the Sangshutai Fault-zone,and the favorable exploration area for the next step in the Yingcheng Formation is the middle and northern sections of the Sangshutai Fault zone.