Oil-gas detection method and device based on seismic signal decomposition

The invention provides an oil-gas detection method and device based on seismic signal decomposition, and belongs to the field of oil-gas geophysical exploration. The method comprises: acquiring seismic post-stack pure wave data of each seismic trace in the work area and horizon data of a target stratum in the work area; determining an analysis time range of a target layer; calculating an attenuation estimation value of each seismic trace at each time sampling point in an analysis time range; generating a time-frequency spectrum of seismic post-stack pure wave data of the seismic trace; decomposing the logarithm spectrum of the time-frequency spectrum at each time sampling point into a group of intrinsic mode functions; selecting a main intrinsic mode function at each time sampling point, and determining an attenuation estimation value at the time sampling point according to the attenuation amount of each main intrinsic mode function at each time sampling point; and in combination with the attenuation estimati