Means of synchronization of independent seismic stations in seismic arrays

Abstract

Basic reasons for different kinds of failures of record synchronization of the independent seismic stations, operating as elements both of domestic and foreign seismic arrays, are established. Proceeding from it, software and hardware are proposed for ensuring reliable and precise synchronization of stations. Their operation is based on periodic fine tuning of the station's analog to digital converter (ADC) sampling cycle by an exact time signal obtained from the GPS receiver. This procedure is executed with minimum or even no additional load on the controller of the seismic recorder. Such an approach allows not only matching each ADC sample to astronomical time, but also to provide simultaneous ADC sampling of all stations in the seis mic array with an accuracy of 10 µs, which is especially important for solving a number of geophysical prob lems. Experimental researches and trial operation of the created equipment are carried out. High reliability of the equipment and compliance of technical characteristics to the purposes of the development are confirmed.

The ADSS-3 broadband stand-alone digital seismic station

“…The reliability and synchronization accuracy of the seismic stations with SSD 3 recorders were studied when operating in a seismic array (Bashilov, Volosov, and Korolev, 2013). They confirmed the reliability of the synchronization system in the array with an error not exceeding a digitizing period of 5 ms.…”

“…This criterion is determined by the ability of seismic recording and processing systems to minimize the impact of various distorting factors on the original seismic signal during the measurement process (Bashilov, Volosov, and Korolev, 2013). To a large extent, these factors are reduced by modern low noise electronics, but this leaves other means for doing it unfulfilled (in particu lar, optimization of coupling of the seismic receiver output with the ADC input).…”