Method and device for inverting sea water depth by use of data of underwater detector and land detector

Abstract

The invention provides a method and a device for inverting sea water depth by use of data of an underwater detector and a land detector. The method comprises acquiring the data of the underwater detector and the land detector, segmenting the data of the underwater detector and the land detector, calculating up and down wave field data of each segment, performing Fourier transform on the up and down wave field data of each segment, calculating the self-correlation power spectrum of each segment and the cross-correlation power spectrum of each segment, calculating a mean self-correlation power spectrum and a mean cross-correlation power spectrum, calculating a normalized correlation power spectrum, calculating a cross-correlation function of the seismic data of the underwater detector and the seismic data of the land detector according to the normalized correlation power spectrum, determining the maximum value of the cross-correlation function, and calculating the sea water depth according to the maximum value. The method for inverting the sea water depth by use of the data of the underwater detector and the land detector is used for solving the technical problem of large error of a sea water depth value calculated by use of the prior art, and achieves the technical effect of effectively improving the seawater depth calculation accuracy.

Description

technical field [0001] The invention relates to the technical field of oil and gas exploration, in particular to a seawater depth inversion method and device for hydrophone data. Background technique [0002] With the development of seismic exploration technology, offshore oil and gas exploration is becoming more and more difficult and deeper, and the requirements for signal-to-noise ratio and resolution of seismic data are also getting higher and higher. 3D seismic can accurately describe reservoirs. Ocean Bottom Cable (OBC) is a combination of offshore and land seismic data acquisition technology, a device that fixes the geophone on the seabed, and high-resolution 3D seismic data can be obtained through the submarine cable. It uses a fixed arrangement with geophones fixed on the sea floor to receive seismic waves, while a ship merely tows the source for seismic wave excitation. In OBC data acquisition, at least three ships are required: a source ship, which is only used ...

AI Technical Summary

Problems solved by technology

[0015] However, the actual hydrophone data and land geophone data contain various noise interferences, especially due to the different effective frequency ranges of hydrophone data (that is, hydrophone data and land geophone data), low-frequency noise (such as : surface waves, etc.) and useless high-frequency distribution are also different, especially land survey data, which contains relatively strong surface wave interference

In addition, the pre-stack hydrophone data also contains strong amplitude energy interference, so the cross-correlation function obtained by directly calculating the cross-correlation using the hydrophone data and land geophone data also contains various noise components. Correlation function, the determined sea depth will inevitably have a large error, which is difficult to meet the actual data processing requirements

Images