Institut Francais Du Pe'trole

G&eacute;rard Thierry

Michel Guion

Van Bui-Tran

R&eacute;nate Bary

Thi Thu Nguyen

A method and system for transferring synchronization data between a central control and seismic recording station and dependent stations in all the cases where the time of transmission through the connection channels between the elements may be liable to too great fluctuations is disclosed. The invention provides a central station (CCU) and intermediate local control and concentration stations (RRS), each connected to local acquisition units (RTU), with a common time reference or clock (H) (that can for example be provided by a satellite positioning network of a well-known type such as the GPS system, or based on the carrier frequency of a radio transmitter) which is picked up by specialized receivers associated with the elements of the seismic device, and in using this common reference to calculate the real transmission time and to local readjust seismic acquisition units (RTU).

Method and system for synchronizing elements of a seismic device using a standard transmission network and an external time reference

Method and device intended for synchronized acquisition of seismic signals by one or more acquisition units suited for seismic signal digitizing, allowing to obtain, for each signal, a series y&lsqb;n&rsqb; of samples of these signals readjusted from a reference time on, from a first series x&lsqb;n&rsqb; of digitized samples of this seismic signal produced from any initial time prior to the reference time. The method essentially comprises detecting a synchronization signal indicative of this reference time (T,), measuring the effective time difference (D) between the reference time and the initial time, determining coefficients of a digital filter (F) suited to compensate for the fractional part (d) of the measured effective time difference, and applying this compensation digital filter to the first series of samples, which allows to obtain a series of digitized samples readjusted from the reference time. In order to accelerate determination of the filter coefficients depending on the difference D observed, the coefficients of a certain number of intermediate filters corresponding to determined fractions of the sampling interval are preferably precalculated. The method can be applied for seismic prospecting or monitoring, earthquake detection, etc.

Growing community of inventors

Villa Blanche, France

Gérard Thierry

Growing community of inventors

Villa Blanche, France

G&eacute;rard Thierry

Gérard Thierry