Method suitable for positioning hydraulic fracturing micro-seismic source

Abstract

The invention discloses a method suitable for positioning a hydraulic fracturing micro-seismic source. The method includes: building a micro-seismic-monitoring observation system, acquiring logging information and other seismic data, building an initial speed model, researching and analyzing regional stratum conditions and perforation records, determining background interference and micro-seismic signal features, performing noise compression on fracturing records and performing effective waveform identification on micro-seismic signals, and using methods such as first break picking and manual intervention to pick the first break travel time of a direct wave, wherein the travel time of the perforation records is used for optimizing the speed model, and other effective events are used for the inversion positioning of the seismic source. The method has the advantages that transverse wave travel time is added on the basis that longitudinal wave travel time is used, the micro-seismic source is positioned by using the longitudinal wave travel time and the transverse wave travel time to perform simultaneous constraining, the inversion uses a method combining global searching and local searching, and the method is high in positioning precision and high in calculation efficiency.

Description

technical field [0001] The invention belongs to the field of seismic data processing methods for oil exploration geophysical fracturing, and in particular relates to the positioning of hydraulic fracturing seismic sources. Background technique [0002] In my country, the discovery of new oil fields is becoming more and more difficult, the development and utilization rate of old oil fields is not high, low permeability oil fields or ultra-low permeability oil fields are rich in reserves, and the exploitation of shale gas is also increasing. Hydraulic fracturing is a relatively practical method of increasing production, and this process involves the issue of fracturing monitoring. Microseismic monitoring During the implementation of hydraulic fracturing projects, as the pressure increases, when the rock exceeds the limit, it ruptures and generates seismic waves. The fractures formed by the rupture are underground, and it is difficult to obtain the spatial position and shape o...

AI Technical Summary

Problems solved by technology

In the selection of inversion methods, there is a type of method that establishes a system of equations through the position relationship between the source and the geophone or linearizes the objective function, and then obtains the real source position of the microseism by solving the system of equations. The results often fail to converge or the positioning accuracy is poor; another kind of representative and commercial microseismic positioning software mainly selects direct or fast grid search algorithm, which has low calculation efficiency when the monitoring area is relatively large , and the positioning accuracy is related to the grid size

Images