Method for monitoring hydraulic fracturing cracks based on pressure fluctuation of closed wellbore

Abstract

The embodiment of the invention relates to a method for monitoring hydraulic fracturing cracks based on pressure fluctuation of a closed wellbore. The method comprises the following steps of monitoring the hydraulic fracturing cracks based on the pressure fluctuation of the closed wellbore according to drilling and completion and logging stratum information, acquiring wellbore parameters, geological parameters and fracturing construction and well completion parameters of a fracturing well and a closed well, and establishing a physical model for crack propagation and closed wellbore pressure monitoring; establishing a 'shaft-plane three-dimensional multi-crack' full-coupling fracturing design calculation model; establishing a calculation model for volume and pressure fluctuation of a closedwellbore in the fracturing process; carrying out smoothing processing according to pressure data calculated in step S30, drawing an evolution diagram of pressure and pressure change rate of the closed wellbore and the injection time of the fracturing well, and establishing a typical plate of the pressure and the pressure change rate of the closed wellbore; and according to the forward models in the step S20 and the step S30, adopting an optimization algorithm to establish an inversion model of closed wellbore pressure monitoring data, and acquiring fitting stratum parameters of actual signals.

Description

technical field [0001] The embodiments of the present invention relate to the technical field of oil and gas field development, in particular to a method for monitoring hydraulic fracturing fractures based on pressure fluctuations in closed well bores. Background technique [0002] Horizontal well staged multi-cluster fracturing is an important technology for the development of low-permeability and unconventional oil and gas reservoirs. At present, microseismic, inclinometer, optical fiber monitoring and other means are usually used to monitor the fracture shape during the fracturing process, so as to obtain the fracture shape during the fracturing process and optimize the construction design in real time. These monitoring methods have their own advantages, but they are generally high-cost monitoring technologies, which occupy a large operating expenditure in oil and gas well fracturing, which is not conducive to the development requirements of low-cost construction operatio...

AI Technical Summary

Problems solved by technology

However, this technology still lacks an effective theoretical basis, and the corresponding relationship between the pressure change of the closed well and the fracture expansion during the fracturing process is not yet clear, and it is difficult for engineers to interpret and analyze the measured data, which reduces the success rate of construction.

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