Analysis of various parameters in soaking: a case study of Permian Fengcheng Formation in Mahu Sag, Junggar Basin, China

Abstract

During the shale oil development process in the Mahu Sag, there is a significant difference in the initial crude oil production after soaking, which is considered to be related to the soak. Therefore, 7 wells in the research area were selected to study the relationship between various parameters in soaking and initial crude oil production under similar control engineering parameters. Selecting parameters with strong correlation to establish a multiple linear regression equation with initial crude oil production and predict the initial crude oil production of Well M57. The results indicate that the initial oil production is negatively correlated with pressure drop rate, porosity, and soaking time. Establishing a multiple linear regression equation as Y =  − 127.1823A—5.20913B + 1.35608C + 73.81473 and predicting initial oil production of well M57 is 16.58 m³/d. Based on the relationship between pressure drop rate and soak time, the pressure curve is divided into four phases. The reasonable soak time is between the lower and upper limits. The favorable soak time for initial crude oil production is between the II and III stage. This study fills the gap in predicting the initial production of shale crude oil in Mahu Sag and can provide guidance for the efficient development of shale oil in the region in the later stage.