Method and device for processing seismic signals
A device, computer program and related method for processing a first seismic signal that includes identifying one portion of a second seismic signal and determining a length of a seismic wavelet. It is also possible to train a neural network by using a plurality of sub-portions of said portion a input variables and at least one second piece of information as a target variable. Said sub-portions of the portion have a length dependent on the length of the seismic wavelet determined. Finally, the method includes determining at least one first piece of geological information based on the first seismic signal using said trained neural network.
1. A method for processing a first seismic signal, the method comprising the following steps:
receiving at least one second seismic signal derived from the emission of a seismic wavelet in a subsoil;
identifying at least one portion of said at least one second seismic signal corresponding to reflections of the seismic wavelet in a reservoir zone of said subsoil;
determining a length of the seismic wavelet;
receiving well data corresponding to said identified reservoir zone;
training a neural network using:
a plurality of sub-portions of said at least one portion as input variables, said sub-portions of the portion having a length dependent on the length of the seismic wavelet determined,
and at least one second piece of geological information according to said well data as the target variable;
determining at least one first piece of geological information based on the first seismic signal using said trained neural network.
2. The method according to claim 1 , wherein the wavelet length is determined according to an autocorrelation calculation of said at least one portion.
3. The method according to claim 1 , wherein the union of the plurality of sub-portions is said at least one portion.
4. The method according to claim 1 , wherein the length of the sub-portions is the length of the seismic wavelet determined.
5. The method according to claim 1 , wherein the length of the sub-portions is between 0.5 and two times the length of the seismic wavelet determined.
6. The method according to claim 1 , wherein the second piece of geological information is a piece of information from a group including a piece of porosity information, a piece of reflectivity information, a piece of density information, a piece of resistivity information and a piece of mineralogical composition information, a piece of gamma-ray log information, a piece of density information, a piece of sound propagation rate information, a piece of permeability information and a piece of saturation information.
7. The method according to claim 1 , wherein the second piece of geological information is a piece of filtered information in a given frequency range.
8. A computer program product containing instructions on a tangible recording medium, said instructions being executed by a processor to implement the method of claim 1 .
9. A device for processing a first seismic signal, the device comprising:
an interface for receiving at least one second seismic signal derived from the emission of a seismic wavelet in a subsoil;
a circuit for identifying at least one portion of said at least one second seismic signal corresponding to reflections of the seismic wavelet in a reservoir zone of said subsoil;
a circuit for determining a length of the seismic wavelet;
an interface for receiving well data corresponding to said identified reservoir zone;
a circuit for training a neural network using:
a plurality of sub-portions of said at least one portion as input variables, said sub-portions of the portion having a length dependent on the length of the seismic wavelet determined,
and at least one second piece of geological information according to said well data as the target variable;
a circuit for determining at least one first piece of geological information based on the first seismic signal using said trained neural network.