Research and Application of Comprehensive Evaluation of Engineering Sweet Spot in Block LX

Abstract

Block LX is a tight sandstone gas reservoir with low porosity and low permeability, and there are the problems of a sharp decline in production and a poor utilization degree of superimposed reserves in the longitudinal gas bearing sand body within a few years after the initial fracturing, which leads to the difficulty of gas field production replacement under the condition of high comprehensive decline rate. By analysing the effect of reservoir characteristics and rock mechanical properties on volumetric fracturing, combined with geological logging data and rock mechanics experimental data of tight sandstone reservoir in Block LX, the paper tries to study the adaptive effect of volumetric fracturing technology in Block LX. The adaptability of volumetric fracturing is evaluated by software simulation of fracturing effect to determine the optimal fracturing construction parameters before the volumetric fracturing gas test is carried out on three wells. The gas test results show that the daily gas production is increased by more than 46.01% compared with that before volumetric fracturing, and the fracturing effect is good. Therefore, it is feasible to use volumetric fracturing technology to overcome the difficulty of low permeability and low gap in Block LX to improve gas production.