Analysis Of The Middle And Shallow Fault System In The Northern Belt Of The Donghaihai Depression And Its Target Optimization

Dongdaohaizi North Central Mesozoic belt is a more realistic realm with highly efficient petroleum exploration.This area accepts the petroleum filling from Dongdaohaizi depression and the west depression of Pen-1 well which are both hydrocarbon depressions.Moreover,Mesozoic have favorable reservoir conditions with shallow burying and high production.Di-20,Di-12,Di-2 and Dixi-12 Cretaceous reservoirs are found in south Di depression.Lunan-1 and Lunan-6 reservoir are also found in Lunan area.Besides that,Cainan oilfield,Mobei oilfield and Shidong-2,Shidong-4,Shidong-15 reservoir are respectively found in Baijiahai depression,Mobei area and Shidong area.The strike-slip fault system of Dongdaohaizi North Central belt is a high speed channel to migrate and ajust hydrocarbon for long time,close to where the reservoir forming conditions of fault blocks target are good.In order to clarify the focus of exploration,several rounds of seismic research are continued to be carried out based on lasting to explore and improve the integrated petroleum geology research results in recent years.The strike-slip fault system of Dongdaohaizi North Central belt is established.It is determined that Mesozoic petroleum exploration should focus on two major fault systems and five expansion to form an "other source,strike-slip fault,block accumulation" exploration mode,guiding petroleum exploration.Among them,Dongdaohaizi Depression petroleum systems have Dixi,Dishuiquan and Baijiahai-Wucaiwan strike-slip faults.The west depression the west depression of Pen-1 well of Pen-1 well have Mobei-Lunan and Shidong area strike-slip faults.Since strike-slip fault is the exploration focus,the nearby fault blocks target are the important exploration type of this area.However,there are the following difficulties in fault block target recognition:complex fracture,small distances between blocks,difficult to identify,low main frequency in seismic data with narrow frequency band,complex wave phenomena appearing in faults zones.To solve the above problem,integrated processing and interpretation shows advantages.Acquisition footprints pressing,post-stack expanding frequency,structure-oriented filtering,multi-attribute fusion assisted fracture recognition technology are combined to summed up a technology processes for fault block target recognition.Research results provide theoretical and technical support to exploration and deployment for study area.Dinan-9 and Di-25 and Shidong-16 wells are successfully deployed.Xishanyao formation of Dinan-9 well is tested to produce 0.7m3 oil and 1.47×104m3 gas daily,improving the success rate of exploration well.This technology is widely applied in middle part of Dinan salient,Shidong and Wucaiwan area to identify a total of 90 various types of traps,the accumulation area of which is 370km2.Di-26 well and Wucai-2 well are also successfully deployed in Dishuiquan and Wucaiwan area.