Calculation method of fractured reservoir front, area and volume based on microseismic monitoring three-dimensional point set

Abstract

The invention provides a method for determining the SRF of the front edge of a fractured reservoir, calculating the area of ​​the fractured reservoir SRA and the volume of the fractured reservoir SRV based on the microseismic monitoring three-dimensional point set. In this method, all three-dimensional data points are first projected onto the horizontal plane, and the Alpha-shape method in computational geometry is used to determine the Alpha shape of the plane point set, and the area surrounded by the calculated SRF is the SRA. Then the microseismic three-dimensional point set is layered in the vertical direction, and the SRF and SRA of each layer are calculated according to the plane distribution of event points in the layer. The area SRA of a single layer is multiplied by the layer height to obtain the volume SRV of a single layer. The total SRV is obtained by summing the volumes. According to the three-dimensional coordinate data of event points monitored by microseismic monitoring, this method determines the SRF shape of the fracture area, and the SRA and SRV quantitatively describe the area and volume of the fracture area, which is used to quantify the production capacity after fracturing and improve the accuracy of fracturing effect evaluation sex.

Description

technical field [0001] The invention relates to the field of geophysics, in particular to a method for determining the front edge of a fractured reservoir (English abbreviation SRF) and calculating the fractured reservoir area (English abbreviation SRF) according to the microseismic monitoring results (ie, three-dimensional point sets) of hydraulic fracturing of oil and gas wells. Abbreviation SRA) and Fracturing Reservoir Volume (abbreviation SRV). Background technique [0002] Hydraulic fracturing is an important measure for oil and gas well stimulation. The artificial fractures formed by hydraulic fracturing can be described by microseismic monitoring results. During hydraulic fracturing, high-pressure fluid is injected into the reservoir, which causes the reservoir rock to rupture and release weak seismic signals. These micro-seismic signals can be received by laying out monitoring arrays underground or on the ground, and then the coordinates of the seismic source can be...

AI Technical Summary

Problems solved by technology

The result of hydraulic fracturing microseismic monitoring is a series of event points in three-dimensional space. For simple strip fractures, the distribution of event points can be used to fit the fracture parameters such as azimuth, length, height, etc., but for complex network fractures , the distribution of microseismic event points has no clear directionality, and the distribution range is relatively scattered, which cannot be described by simple parameters such as azimuth, length, and height.

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