Feasibility Study Of Horizontal Well Development In Puguang Continental Gas Reservoir

In recent years,a great breakthrough has been made in the exploration of continental gas reservoir in Puguang.The reserves of Xujiahe formation are abundant,so that it will become an important part of replacement reserve in Puguang.However the continental gas reservoir in Puguang belongs to tight gas reservoir which has the characteristics of low permeability and low productivity,so that it is very difficult to develop this gas reservoir.It has no economic benefit to be developed with vertical Wells.It also has attempted to complete a inclined shaft with large displacement and a horizontal well in this area.Both of them put into production after fracturing.It obtain higher yield in the early,but the stable production period is short with the production declines rapidly.So that whether the the horizontal well can develop the continental gas reservoir in Puguang with great benefits will be a key factors.In this paper we understood and evaluated of dynamic characteristics of gas reservoir by studying on reservoir geological of continental gas reservoir in Puguang and the means of modern well test analysis and production dynamic analysis based on the date of trial-produce and test.We aimed at the horizontal well' s productivity by optimization of horizontal well and fracture parameters with the means of model establishment and numerical simulation.Finally,to determine the feasibility of development in Puguang continental gas reservoir with horizontal well.(1)To demonstrates development engineering feasibility of Puguang continental gas reservoir with horizontal well by studying on in-situ stress and stratigraphic characteristics.The study show that the reservoir of Xujiahe possess favorable geological conditions of horizontal well drilling.(2)We confirmed the Puguang continental gas reservoir dynamic parameters,based on the well test and performance analysis of a highly deviated well in Puguang continental gas reservoir named Pulu 2.The result provides a basis for horizontal wells production forecast and parameters optimization.(3)As the result that,the productivity of a horizontal well has relationships among the length of horizontal,fissure length,fracture number and the conductivity of hydraulic fracture by studying on the main factors influencing the fracturing horizontal well productivity.an optimal design model of the fracture parameters which is appropriate for Puguang continental gas reservoir has been set up.It will provide guidance for Puguang continental gas reservoir on horizontal well fracturing design.(4)Predicted the development indices of a optimization horizontal well.it shows that the recovery will be 61% after 20 years with high-yield.Research shows that developing Puguang continental gas reservoir by horizontal well is feasible with good economic benefit.