A Synchronization Method for Large-scale Seismic Data Acquisition

Abstract

The invention relates to a synchronization method for large-scale seismic data acquisition. The central control and recording unit gives commands to specify the acquisition station at the end of the survey line; the cross station gives a delay calibration command, and the cross station passes the synchronization pin of the interface module. Given a TB pulse signal, each collection station measures the delay T1 to the collection station at the end of the survey line, and the intersection station takes out the measurement result T1max from the return value of a station closest to the intersection station, and the intersection station sends each The collection station gives a correction value T2=1ms-T1max. When the cross station gives the TB pulse, each collection station will delay T1+T2 after receiving the TB pulse and then use the TB signal as the real data collection start signal ; All collection stations will start data collection at the same time 1 ms later based on the TB signal given by the cross station; the time error of the TB signal in each station is 0.5us.

Description

technical field [0001] The invention relates to a synchronous method for realizing large-scale seismic data acquisition by seismic instruments in large-scale petroleum seismic exploration. Background technique [0002] There are currently two synchronization methods commonly used in instruments for seismic data acquisition in a large area, 1) using GPS synchronization pulse signals to achieve instrument synchronization, and 2) using a fixed delay correction method to achieve instrument synchronization. Both methods have their own insurmountable defects. [0003] The method of using the synchronous pulse signal of GPS to realize the synchronization of the instrument has higher requirements on the physical environment where the instrument is placed, and the instrument must be placed in a place where the GPS signal can reach. In the process of oil exploration, various harsh environments will be encountered, such as rivers, deep valleys, forests and bridges, etc., where GPS sig...

AI Technical Summary

Problems solved by technology

This method is relatively simple to implement, but the error it brings is relatively large.

Because the transmission delay characteristics of the cable to the signal will change with the external temperature, humidity and the aging characteristics of the cable itself, using a fixed value to correct the delay characteristics of the system in different environments cannot obtain accurate results

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