Method for recognizing and collecting microseism events in well

Abstract

The invention provides a method for recognizing and collecting microseism events in a well and belongs to the field of microseism monitoring. The method comprises the steps that (1) orientation rotation is conducted on each receiving point recorded in the even monitoring process; (2) for records obtained after rotation is conducted, a characteristic function value CFs of each receiving point at each moment is calculated; (3) an event superposition energy function L(t) is calculated through a time difference scanning technique; (4) the seism starting time ti of events is automatically detected through self-adaptive threshold values; (5) the peak value time of S waves of a set of events is collected and checked, and the jumping time of the S waves is collected and checked; (6) for each receiving point, a characteristic function value CFp is calculated for each time point within a fixed time interval Tspmax before the jumping time of the determined set of S waves; (7) the peak value time of each receiving point of P waves of the set of events is collected and checked, and the jumping time of the P waves is collected and checked.

Description

technical field [0001] The invention belongs to the field of microseismic monitoring, and in particular relates to a method for identifying and picking up microseismic events in wells. Background technique [0002] With the further intensification of the tension between supply and demand of oil and gas resources, the field of oil and gas exploration has turned its attention to increasing oil and gas production to tight sandstone and shale. my country's abundant tight sandstone and shale oil and gas resources will become the main pillar of future oil and gas resources. However, the exploitation of tight sandstone and shale oil and gas resources relies on hydraulic fracturing technology. The purpose of hydraulic fracturing is to change the formation structure through pressure to form fractures that are conducive to oil and gas migration. earthquake event. Microseismic monitoring can provide a basis for hydraulic fracturing design and fracturing effects, and then serve for en...

AI Technical Summary

Problems solved by technology

[0004] Therefore, the current method of identifying and picking up microseismic events using manual methods as the primary means has the problems of high work intensity, inaccurate picking up of weak signals, and difficulty in judging P-wave and S-wave seismic phases. Hydraulic pressure provides the basis

For the automatic identification and picking of microseismic events, although the current method has identified and picked up some events, it has not judged the seismic phase of the event, nor has it effectively paired the P-wave and S-wave event pairs from the same source. To a certain extent, it has caused difficulties in the follow-up processing of microseismic monitoring

[0005] To sum up, the current microseismic monitoring has the problems of long event monitoring time, large number of events, weak signal, low efficiency of manual event identification and picking, and real-time monitoring.

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