A combined rapid positioning method and system for microseismic p and s waves in a borehole

Abstract

The invention relates to a P and S wave combined quick positioning method and system for microseism in a well, and the method comprises the steps: a, obtaining the microseism data of the same event, carrying out the vector decomposition of the microseism data of the same event, and obtaining two vertical azimuth angles of a three-component detector; b, building the function relation, which takes the three-component detector as the start point, between a vertical depth H and a horizontal distance L according to the snell law; c, building a P&S wave depth target function related with the position of a seismic focus, enabling the target function to be minimized through depth scanning, calculating the vertical depth and horizontal distance of the seismic focus relative to the three-component detector, and achieving the P and S wave combined quick positioning. The method just employs two vertical azimuth angles of the three-component detector, builds the P&S wave depth target function related with the position of the seismic focus according to the snell law, enables the target function to be minimized through depth scanning, and can achieve the P and S wave combined quick positioning.

Description

technical field [0001] The invention relates to the field of micro-seismic positioning processing in wells, in particular to a rapid positioning method and system for micro-seismic P and S waves in wells. Background technique [0002] Microseismic fracturing monitoring technology is one of the key technologies in the development of oil and gas fields in unconventional tight sandstone gas and shale gas reservoirs. According to the source information located by inversion, fracture properties (principal stress direction, fracture width, density, etc.) can be obtained. ), used to evaluate fracturing effects, analyze fracture induction rules, optimize well layout, etc. Therefore, in microseismic signal processing, the ultimate goal is source location, also known as the core technology of microseismic signal processing. [0003] In-well microseismic monitoring is one of the microseismic observation methods, which is characterized by downhole three-component reception, high micros...

AI Technical Summary

Problems solved by technology

[0004] One is forward modeling based on P-wave and S-wave event travel time. Representative algorithms include network search method, simulated annealing method, geiger method, etc. The advantage is that it is easy to implement. It is difficult to pick up accurately, which will affect the positioning results;

[0005] The second positioning idea is based on wave equation convolution. Representative algorithms include interferometry, reverse time migration, and passive source imaging. The advantage is that it does not need to pick up the first arrival of the event. The disadvantage is that it requires high data signal-to-noise ratio and velocity model. , the computational cost is high

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