Enrichment Of Residual Oil At The Edge Of Fault Of Putaohua Oil Layer In Weixing Oil Field And Its Potential Digging Scheme

Weixing oil field is an important part of Daqing peripheral oil field.The Putaohua oil layer is a key development level in the research area,However,due to long-term high-intensity mining,rapid water-elevation and complex fault development,the distribution of remaining oil is not clear.Base on many theories and methods of sediment logy,petroleum geology,logging geology and many other aspects to study the position of the fault plane,this paper makes in-depth research on the plane location,geometric characteristics and the main controlling factors of the remaining oil distribution in the fault zone.The five major controlling factors for residual oil enrichment at the edge of the fault are summarized,and the potential areas for further development are pointed out,which has important guiding significance for the remaining oil production of the entire oil field.The paper starts with the correction of fault quality and re-analyzes the position of the fault plane in the entire study area.On this basis,statistical analysis of the fault geometry,and then the main control factors of the residual oil distribution at the edge of the fault are made clear on various types of information data such as fault type,micro-amplitude structure,fault congruence,reservoir,and well pattern.:(1)From the type of fault,the inferior normal fault is superior to the upper one,and the normal positive fault is superior to the inferior one.(2)There is a large amount of residual oil in the positive micro-amplitude tectonic zone;(3)The average thickness of the sandstone of the contemporaneous faults is larger than the average thickness of the sandstone of the footwall and the north-south fault increases with the growth index of the fault.the overall average thickness of Sandstone on the footwall increases slowly,the average thickness of sandstone has no obvious change;East-West faults,with fault growth index increased on the average thickness of sandstone decreases,lower the average thickness of sandstone did not change significantly;(4)The control of the remaining oil in the reservoir is mainly manifested in two aspects : From the dynamic point of view,the lateral edge zone controls the planar distribution of the remaining oil;from the static aspect,the thickness and moisture content of sandstone control the location of remaining oil enrichment site;(5)The well pattern can be divided into three types: There are residual oils in the sand bodies in the fault side well network control poorly and in the “dead zone” between the production wells,and there is residual oil between the injection wells and the boundarybetween the oil and water at the edge of the fault.Based on the analysis of the matching elements and the main controlling factors of the remaining oil at the edge of the fault,we get the genetic type pattern of the remaining oil at the edge of the fault,and divide it into 3categories and 6 subcategories:(1)Structural Causes: Positive micro-amplitude structures form residual oil and faults to form remaining oil;(2)Cause of sand body: the side margin with the sand body formed residual oil,inter-layer interference to form residual oil and the remaining oil accumulates at the top of the river to form remaining oil;(3)The well pattern is mainly due to imperfect injection and production and formation of a large amount of residual oil.On the basis of the above research,based on the study of the structure of Putaohua oil layer,sandstone,water content and some well locations,a total of 52 potential areas of residual oil from the faults in the satellite oil field were analyzed.Finally,under the guidance of the potential area,9 proposed well sites were designed,all located near the fault.Among them,there are 3 wells in the dense well network area,mainly infill wells,and sparse wells in the well pattern.In the area,6 wells were identified,mainly supplemented wells.