Sensitivity Analysis of Influencing Factors of Production for Fractured Horizontal Wells in Shale Reservoir

Major productivity breakthroughs have been achieved in key production layers of Jiyang shale, such as lower Es3 and upper Es4 producing layer of Shahejie Formation, and remarkable development have been gained. However, it is also limited by short production time, large production difference of single well, and unclear of production influencing factors. Comprehensive analysis of the main controlling factors of production for horizontal shale oil wells has become the research focuses. Field production data was taken to clarify the influence of various factors on the production of horizontal wells. Grep correlation analysis and principal component analysis were used to quantitatively analyze the sensitivity of 90-day average oil production, 180-day average oil production, and 270-day average oil production to the influencing factors, such as the amount of fluid used and the sand added. Research indicates that the amount of fluid used, the amount of sand added and the number of fracture events are the main engineering parameters affecting the production, while the content of gray matter, TOC and shale porosity are the main geological parameters affecting the production. The influence of geological factors on production gradually increase, while that of engineering factors on the production is gradually weakened in the late flowing production stag. The main controlling factors and variation rules of the production are preliminarily identified, which could provide guidance for the deployment of shale oil wells and fracturing design.