Micro-seismic event detection method and system by using non-homogeneous polynomial

Abstract

The invention discloses a micro-seismic event detection method and system by using a non-homogeneous polynomial. The method comprises the following steps: sequentially collecting micro-seismic signalsof N points in a detection region, and forming a micro-seismic signal sequence comprising N micro-seismic signals; generating N first-order difference sequences, N second-order difference sequences and N expected difference sequences; calculating a non-homogeneous polynomial kernel value of each point of the micro-seismic signal sequence; and determining whether a micro-seismic event exists in each point by utilizing the non-homogeneous polynomial kernel value of each point. According to the invention, the sparsity of a micro-seismic event (the ratio of power value change in the whole power data is small) and the statistical property of noise are utilized, and from the perspective of probability statistics, the difference of the non-homogeneous polynomial kernel between the microseismic signal and the background noise is adopted to detect the microseismic event, so that first arrival pickup is realized, the influence of the noise on the power change is avoided, the power change causedby strong noise is effectively eliminated, and the microseismic event detection precision is improved.

Description

technical field [0001] The present invention relates to the technical field of microseismic event detection, in particular to a microseismic event detection method and system using inhomogeneous polynomials. Background technique [0002] Hydraulic fracturing microseismic monitoring technology is an important new technology developed in the fields of low permeability reservoir fracturing, reservoir driving and water flooding front in recent years, and it is also an important supporting technology for shale gas development. This technology arranges a multi-level three-component geophone arrangement in adjacent wells to monitor the microseismic events generated in the hydraulic fracturing process of the target interval of the fracturing well, and inverts the microseismic events to obtain parameters such as the source position, so as to describe the hydraulic fracturing The geometry and spatial distribution of fracture growth during the process provide real-time information on t...

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Problems solved by technology

In contrast, manual methods are often used in production, which is time-consuming and labor-intensive, with poor accuracy and reliability, and the quality of picking cannot be guaranteed, nor can it handle massive amounts of data.

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