Node clock drift correction method and device based on near-offset seismic signal

Abstract

The invention provides a node clock drift correction method and device based on a near-offset seismic signal. The method comprises the steps: setting the position relation between shot points and nodes in a seismic observation system to make shot points with the near offset cover the shot points in a time period when the node starts collection and the node ends collection; determining a near offset range according to the position relationship and the water depth, so that the first arrival wave of the seismic signal to be acquired is a direct wave; performing linear dynamic correction on the obtained near-offset seismic signal by using the sound velocity in water to obtain a near-offset corrected seismic signal; comparing the near-offset correction seismic signal first arrival wave with theseismic signal at the moment T0 to determine a clock drift amount and a clock drift model; and sorting the near-offset correction seismic signals, and performing clock correction on the sorted near-offset correction seismic signals by using the clock drift model to obtain corrected seismic signals. According to the scheme, node clock drift correction can be accurately realized.

Description

technical field [0001] The invention relates to the technical field of node clock quality control, in particular to a method and device for correcting node clock drift based on near-offset seismic signals. Background technique [0002] In the seismic exploration data acquisition of the submarine node (the full name of OBN is Ocean Bottom Node, which is a multi-component seismometer located on the seabed and can independently collect and record seismic signals), each node (ie, the receiver point) operates independently after startup There is no wired or wireless connection of external monitoring equipment, so compared with the previous land and sea tow cable wired or wireless remote sensing equipment, the node equipment lacks the GPS synchronization signal for real-time clock service, and cannot perform clock synchronization correction in real time . Each node device will have clock drift after the acquisition is completed. Generally, the clock drift of the node underwater f...

AI Technical Summary

Problems solved by technology

But now that node devices have just emerged in the geophysical prospecting industry, many people do not know that node devices have node clock drift. It is urgent to establish a node clock drift correction method to accurately correct the clock drift.

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