Sensitivity calibration method and device for marine air gun near-field detector

Abstract

The invention provides a sensitivity calibration method and device for a marine air gun near-field detector. The sensitivity calibration method for the marine air gun near-field detector comprises thesteps: collecting the wavelet signals of each marine air gun in a marine air gun array through the near-field detector; and generating a sensitivity calibration value of the near-field detector according to a pre-acquired maximum amplitude standard value which can be generated by the marine air gun, the distance between the marine air gun and the near-field detector and the wavelet signal. According to the method, the accurate and effective near-field detector calibration sensitivity can be obtained, the industrial production requirement can be met, the near-field wavelet acquisition precision is effectively improved, and more accurate near-field wavelet data can be provided for air gun source near-field wavelet quality control and air gun array far-field wavelet synthesis by utilizing near-field wavelets.

Description

technical field [0001] The invention relates to the technical field of offshore oil exploration, in particular to the acquisition and quality control technology of airgun source near-field wavelet signals in marine seismic exploration, and in particular to a sensitivity calibration method and device for a marine airgun near-field detector. Background technique [0002] In marine seismic exploration, the air gun array is used as the main excitation source, which is composed of multiple single guns or coherent guns formed by multiple groups of double guns, which are combined according to a certain spatial geometric relationship. During the air gun excitation process, in order to be able to record the wavelet signal of each single gun or each group of coherent guns, a near-field detector is usually installed at a distance of 1m above each single gun or each group of coherent guns in the air gun array. The near-field wavelet signal collected by the near-field detector is of grea...

AI Technical Summary

Problems solved by technology

However, in the process of field seismic exploration, on the one hand, the near-field geophone is installed in the air gun array on the deck of the exploration ship, and is connected to the air gun excitation and acquisition system in the cabin through a long cable, which will cause a certain signal energy attenuation On the other hand, the airgun source will frequently generate high-voltage shocks to the near-field geophone during the continuous excitation process, making the near-field geophone work for a long time in a high-pressure, high-intensity environment, and its inherent sensitivity will change.

As a result, the numerical accuracy of the airgun near-field wavelet recorded by it will be reduced

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