Parameter Optimization Of Fractured Horizontal Well In Jilin Oil Field Block A Reservoir

Jilin oil field block A has a huge source of tight oil,and it shows a brightness exploration future.But tight oil exploration is almost started in this field.Although it is a common sense that using fractured horizontal wells to develop the tight oil formation,but there is little knowledge of the special flow mechanism of tight oil,the parameters that affecting the production or the effective parameters of fractured horizontal wells development.So it is eager to start a flow mechanism study on block A based on its special flow mechanism and actual formation characteristics to understand the reasonable development parameters of tight oil fractured horizontal wells and develop block A tight oil field effectively.First of all,through others'literature research survey,we get to the main development block and main development formation of Jilin tight oil and it is known that there are some special flow mechanism in Jilin tight oil formation,including the stress sensitivity,threshold pressure gradient and rich in natural fracture.Then we conduct analytical model research taking these three special flow mechanism into consideration using fractured vertical well and fractured horizontal well model.Through these research,we got to know that in the condition of Jilin oil field block A tight oil reservoir,the production of fractured vertical well and fractured horizontal well decrease with the increasing of stress sensitive parameter,and when the parameter is lower than 1_×10^-51/kPa,the stress sensitive can be ignored;the production of fractured vertical well and fractured horizontal well decrease with the increasing of threshold pressure gradient,and when the parameter is lower than 1_×10^-4MPa/m,the threshold pressure gradient can be ignored;when there is a lot of natural fracture in reservoir,the more the stored energy and the bigger interporosity flow coefficient the higher the initial production,but in comparison,the stored energy has less influence in the later decline discipline and the smaller the interporosity flow coefficient,the slower decline the later production.At last,we use numerical model with taking these three mechanisms into consideration,to optimize the fractured parameters and well pattern parameters.The optimization shows the horizontal well length should be between 800m and 1000m,fracture half length should be between 200m and 250m,fracture inter space should be between 100m and 150m,dimensionless fracture conductivity should be between 500 and 1000 and the well space should be better twice the fracture half length that is when the optimized fracture half length is 200m to 250m,the well spacing should be between 400m and 500m.Through the study above,we have a further understanding of Jilin oil field block A tight oil reservoir and provide a theoretical support to the effective development of block A in a certain degree.