Study On Borehole Stability Of Shale Gas Horizontal Wells In Fuling

In the process of drilling hole collapse,necking,fracture and wellbore instability problems cost of huge losses to the oil and gas exploration and development Therefore,to determine the safe mud weight window of drilling fluid system is reasonable and appropriate drilling technology to avoid hole collapse,necking and rupture,instability of technical personnel in drilling engineering has been committed to solve the technical problems.Shale gas is the current focus on the development of national energy strategy,horizontal wells is the main means of efficient development of shale gas,shale gas to ensure wellbore stability of shale gas exploration and development,the premise of safety Fuling shale gas field is the first to enter the commercial development of shale gas fields in China,research in this area has important significance on wellbore stability of domestic shale gas exploration and productionFuling Jiaoshiba area is shale formation which have features such as high brittleness,weak water sensitivity,bedding fractures.Different drilling direction of horizontal well drilling has great influence on the safety of horizontal wells.The rock mechanics parameters obtained through the research by stress state and establish reasonable mechanical model,determine the reasonable security density window of drilling fluid,ensure wellbore stability during drilling.These studies complete the analysis of rock mineral component in Fuling Jiaoshiba,the rock mechanics parameters of the area,a section of rock mechanics.The stresses of Jiaoshi area of focus,determination of pore pressure,establish stress pore pressure profile.Selects and analyzes the influence of wellbore stability of Fuling coke dam area of key factors,the analysis of formation strength,wellbore trajectory,bedding inclination and to the formation collapse pressure of weak surface inclination angle and direction of the strength criterion and the mechanics model is taken into account.To determine the safe mud density window,provide the basis for subsequent drilling design and construction.