Evaluation Of Fracturing Effect Based On Formation Quality Factor Q

Microseismic monitoring is an important method to evaluate the hydraulic fracturing effect of tight reservoirs.Changes in structural characteristics,porosity,permeability,saturation,etc.of the formation during fracturing will result in changes in the formation quality factor Q.Therefore,the fracturing range and fracturing effect can be predicted by Q-value estimation.Q-value attenuation has achieved important results in the detection of carbon dioxide sequestration,but its research on hydraulic fracturing evaluation is obviously insufficient.This paper analyzes the advantages and disadvantages of different Q-value estimation methods,and improves the existing methods.A weighted exponential centroid frequency shift method based on energy spectrum is proposed.The new method improves the noise immunity of the Q value estimation and reduces the influence of the wavelet waveform on the extracted Q value.The ground model is simulated by numerical simulation method,and the relative Q values recorded by different detectors are calculated,and the Q-value anomaly region is inverted.In this paper,the conventional Q-value extraction method is improved,and the weighted exponential centroid frequency shift method based on energy spectrum is proposed and applied to the inversion Q value estimation of the stratum model.The preliminary verification is to estimate the underground fracturing range by calculating the Q-value anomaly feasibility.