Well Pattern Study In Developing Horizontal Well Of Extra-low Permeability Reservoir

An increasing number of horizontal wells have been employed in the development ofextra-low permeability reservoir in recent years. In order to improve developmenteffectiveness of low and ultra-low permeability reservoir, horizontal well development hasbeen an important means of increase the degree of reserves control and improve the oil-fielddevelopment efficiency, it has been widespread U9ed at home and aboard.Research area located in southwest of yishan slope of a secondary structure unit in OrdosBasin, simple building unit, main layer is Chang4+5, only local has some tiny nosingstructure, not to see faultage and other types of stress, it is the main reservoir of formationcontrol, major reservoir concentrated and large area distribution, porosity betweens4.72%¹0.79%, the avera2ge is8.41%, the permeability betweens0.04-21.62×10^-3m², the2average is3.17x10^-3μm, it belongs to extra-low porosity,low permeability and lithologicThis paper based on the study of geological characteristics of chang4+5, do thecomprehensive evaluation of reservoir. Under the specific geological condition, factors whichinfluence the capacity of horizontal well are studyed, come to the I aw of capacity analysis. Byanalytical method and numerical simulation method, through many plans demonstration,research for the best horizontal well pattern adapts to the reservoir geological characteristics,and then forecast development effectiveness. It is quite conducive to increase oil productionand cost-effective development of low and ultra-low permeability reservoir, and providereference for developing low permeability reservoirs in Ordos basis U9e fractured horizontalwell pattern and parameter of favorable well pattern.