A method and device for predicting sweet spots in tight gas fracturing engineering

Abstract

The embodiment of the invention discloses a prediction method and device for a tight gas fracturing engineering sweet spot. The method comprises the following steps that: according to a microseismic monitoring four-dimensional image, determining a distribution diagram for first plane stress weak spots around a shaft; adopting a preset prediction technology to predict the stress weak spots around the shaft; according to the monitored distribution diagram for first plane stress weak spots, optimizing prediction parameters, and enabling the predicted stress weak spot distribution to be consistentwith the monitoring result of the distribution diagram for first plane stress weak spots; according to the prediction technology and the optimized prediction parameters, predicting second stress weakspots around the shaft, and obtaining a distribution diagram for second plane stress weak spots; and according to the distribution diagram for second plane stress weak spots, carrying out artificialfracture extension direction prediction, and predicting a fracture formation area with preset complexity as an engineering sweet spot position. By use of the scheme of the embodiment, the engineeringsweet spot position of each reservoir is accurately obtained before well spacing, and well spacing on the engineering sweet spot position is favorable for the fracturing formation of a complex seam net, and the exploration and development effect of a tight gas deposit is improved.

Description

technical field [0001] Embodiments of the present invention relate to tight gas reservoir fracturing engineering sweet spots technology, especially a method and device for predicting tight gas fracturing engineering sweet spots. Background technique [0002] The effect of tight gas fracturing is closely related to the reservoir physical properties and fracture morphology. According to the statistical analysis of tight gas fracturing wells, the gas production of reservoirs with good physical properties is below 30,000 m3, but the reservoirs with poor physical properties are in the After the formation of complex cracks, the production capacity is more than 100,000 cubic meters. At the same time, the physical property of the reservoir is the nature of the reservoir itself, which is difficult to change, but it is possible to form complex fractures by changing the fracture morphology of fracturing, so as to achieve the purpose of high production. [0003] At present, there is a ...

AI Technical Summary

Problems solved by technology

In the prediction of natural fractures, the commonly used method is to study through post-stack seismic attributes, using local structural entropy discontinuity detection, ant body, high-precision curvature attributes, coherent body analysis, dip angle, azimuth and other attributes to analyze macroscopic fractures. The identification and prediction of developmental characteristics, because these methods involve the selection of many parameters, some parameters cannot be obtained accurately, and there are also high requirements for personnel experience, so the prediction results are quite different from the actual results. Few more mature methods are applied

There are many methods for identifying the direction of in-situ stress, and the application results are accurate. However, in terms of prediction, the stress field prediction model is mainly established through finite element numerical simulation, but it is difficult to achieve accurate prediction.

In conventional research methods, the accuracy of the prediction results of a single factor is difficult to guarantee, and the superposition of the three factors can accurately predict the engineering sweet spot, and the accuracy of the results is even lower

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