Study On The Formation Mechanism Of Complicated Fault-block

The complicated fault-block hydrocarbon reservoir is the important pool type in the eastern fractured basins of China. Based on the geology, exploitation, seismic, well drilling and logging date , the structural styles of complicated fault-block are summed up and then the origin of the complicated fault-block is researched with structural analysis. A complicated fault-block usually locates a positive local structure, so the origin of the structural setting could be used to interpret the formation mechanism of complicated fault-block. There are four styles of structural setting in complicated fault-block such as central uplift belt, rolling anticline, fault zone and broom fault . As the basic feature of the complicated fault block, the number of the fault is more and the scale of the block is little. Based on the active duration, the scale and the control of evolution and sedimentary, faults in Jiyang Depression is divided into five levels. After dozens of exploitation, the crude oil that is easily exploited has been extracted out, and the remaining oil is in disperse state. So the exploit action of remaining oil is the main task, and the low-grade fault is one of the main control factors of remaining oil . Therefore the vegetal law of low-grade fault is analyzed and five kinds of forecast methods of the low-grade fault is also put forward. Finally, the relationship between the low-grade fault and remaining oil is simply studied.