Sudong Mawu5 Gas Reservoir Geological Model And Feasibility Analysis Of Horizontal Well Development

Sudong mawu5 gas reservoir is located in the northwest of Ordos basin which is a typical large area,low abundance and low permeability of dense carbonate gas reservoir.The existing vertical gas well production capacity and the overall block development efficiency are low.Horizontal well technology is an effective means for improving the productivity of low permeability gas reservoir,but the adaptability of horizontal well in this block has no system thorough research.This paper demonstrate the adaptability of horizontal wells from geological and development aspects.For the geological aspect,we discuss the adaptability from gas reservoir depth,effective reservoir thickness,anisotropy,βh,permeability and gas supply area,and found that all of these factors meet to the horizontal wells development conditions except effective thickness.For the development aspect,we mainly demonstrate the adaptability from gas production per thousand meters depth.The results showed that Sudong mawu5 gas reservoir geological characteristics conform to the conditions of horizontal well development.The horizontal well productivity analysis found that the sensitivity factors order that affect productivity is: skin factor,permeability,thickness,horizontal length,formation pressure and reservoir anisotropy.The optimization results of parameters of horizontal well are,horizontal extension direction should be NW-SE direction,horizontal section length should be between 1000~1200m.Fracture parameters were optimized by the numerical simulation software.Fracture half length 100~150m,fracture flow conductivity 30~40μm2·cm,fracture number 4~6,the angle of fracture direction and the extension direction of horizontal section is 90°.We established Sudong mawu5 gas reservoir high-precision geological model and determined that mawu51 layer as the main development zone,mawu52 layer as the subsidiary development zone.Finally optimize the form of horizontal wells pattern through the numerical simulation.Thesis research results can provide basis for the field of economic,efficient and reasonable development,and the feasibility of horizontal well development of similar gas field has a certain reference value.The results of research may be useful for gas field manager to develop more effectively and rationally,in addition,it may be the common reference to other similar gas fields to some extent.