Microseism monitoring and positioning method based on full-waveform vector offset superposition

Abstract

The invention discloses a microseism monitoring and positioning method based on full-waveform vector offset superposition. The purpose of monitoring and positioning microseisms is achieved by the data recorded by an earth surface three-component geophone through the method of vector superposition of the three components of P waves, SH waves and SV waves. The microseism monitoring and positioning method is suitable for detecting microseism signals, particularly, under the conditions that microseism energy is very weak caused by rock failure in the fracture improvement process and a traditional method loses efficacy, the effect of microseism detecting can be greatly improved, the defect that only microseisms with large energy can be detected in a traditional method is overcome, more microseisms with weaker signals can be detected, and the effect of fracture improvement can be more comprehensively monitored. According to the method, a good effect is achieved on monitoring of earth surface microseisms, very weak microseism signals can be detected, combined positioning of the P waves and the S waves can be conducted, and therefore the positioning precision is greatly improved.

Description

technical field [0001] The invention relates to the field of microseismic monitoring technology for unconventional oil and gas development, more specifically, to a full waveform-based monitoring system capable of extracting microseismic signals with a very low signal-to-noise ratio and monitoring the effect of fracturing in unconventional oil and gas development. Microseismic monitoring and positioning method based on vector migration stacking. Background technique [0002] Fracturing is a key technology to enhance unconventional oil and gas recovery. Currently, the only way to monitor the effect of fracturing is to study the microseismic effects of rock rupture during fracturing. The use of microseismic can also guide and optimize fracturing reconstruction, reduce pollution to the natural environment and reduce induced earthquake disasters. At present, downhole observation is the main means of microseismic monitoring. However, the cost of downhole observation is too high...

AI Technical Summary

Problems solved by technology

However, the microseismic energy produced by fracturing in the process of unconventional oil and gas exploitation is very small, and generally located at a depth of 3-4 km underground, the seismic wave is already very weak when it reaches the surface, and it is difficult to detect effective seismic waves by the above two methods. microseismic signal

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