Method and device for determining travel time of seabed seismic reflected wave

Abstract

The invention relates to a method and device for determining travel time of seabed seismic reflected wave and belongs to the field of seismic survey. The method comprises the steps of 1, acquiring seismic data of each seismic channel acquired; 2, determining sea water depth of each detection point based on the seismic data; 3, using a three-dimensional interpolation algorithm to establish a seabedmodel; 4, determining stack velocities or root-mean-square velocities, with the sea level as a base level, of multiple discrete points on the basis of seismic data historically acquired in sea leveltowing observation manner; 5, determining vrms of each sampling point on the basis of areal stack velocities or root-mean-square velocities, with the sea level as the base level, of the multiple discrete points as well as the seabed model; 6, for each sampling point, determining vrms' of the sampling point based on the vrms of the sampling point; 7, determining travel time t of the seabed seismicreflected wave of each sampling point from seismic data of each seismic channel, wherein an equation is shown in the description. By using the method and the device, it is possible to improve the accuracy of pre-stack time migration results.

Description

technical field [0001] The invention relates to the field of seismic survey, in particular to a method and device for determining the travel time of seabed seismic reflection waves. Background technique [0002] In the field of marine seismicity, the sea-level streamer observation method is commonly used in recent years, which is to set the shot point and the receiver point at sea level, and use the Kirchhoff pre-stack time migration method to calculate the pre-stack time offset. However, the sea level streamer observation method is easily affected by the tide and sea surface waves, making the observation data inaccurate. People have proposed a submarine seismic observation method. In the submarine seismic observation method, the shot point is set at the sea level, and the receiver point is set at the seabed. Submarine seismic observation methods can be divided into two categories, the first one is OBC (Ocean Bottom Cable, submarine cable) method, that is, the four-componen...

AI Technical Summary

Problems solved by technology

For the submarine seismic observation method, since the shot point is set on the sea surface and the receiver point is set on the seabed, the receiver point and the shot point are not on the same plane. The timing is inaccurate, which leads to inaccurate results of the calculated prestack migration time

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