Abstract: The present invention relates to a method and system for processing seismic data. Seismic data indicative of at least a time-dependent seismic trace are transformed into time-frequency domain using the S-transform. The transformed seismic data are processed for determining at predetermined time instances an instantaneous amplitude and a dominant instantaneous frequency. Based on a quotient of the instantaneous amplitude to the dominant instantaneous frequency seismic data indicative of a likelihood of a presence of hydrocarbons are then determined which are then graphically displayed. The method and system for processing seismic data provides a powerful tool for determining the likelihood of a presence of hydrocarbons based on a double peak hydrocarbon signature in the quotient of the instantaneous amplitude to the dominant instantaneous frequency.