Method for calculating SRF, SRA and SRV based on micro-seismic monitoring three-dimensional point set

Abstract

The invention provides a method for calculating SRF, SRA and SRV based on a micro-seismic monitoring three-dimensional point set. The method comprises the steps of firstly projecting all three-dimensional data points to a horizontal plane, determining the Alpha shape of a planar point set by adopting an Alpha-shape method in the computational geometry, and calculating the area surrounded by the SRF, wherein the calculated area is the SRA; and then layering the micro-seismic three-dimensional point set in the vertical direction, calculating the SRF and the SRA of each layer according to plane distribution of in-layer event points, wherein the SRA of a single layer is multiplied by the layer height so as to acquire the SRV of the single layer, and the sum of the volumes of all layers is the total SRV. The method provided by the invention determines the SRF shape, the SRA and the SRV of a crack zone according to event point three-dimensional coordinate data of seismic monitoring so as to quantitatively describe the area and the volume of the crack zone, thereby being used for quantitatively estimating the production capacity after being fractured, and improving the accuracy of fracturing effect evaluation.

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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