1. A method of identifying a clathrate deposit in a subsurface from seismic data, the method comprising using a computing system in: generating a land surface or sea floor digital image from post-stack seismic data; determining a clathrate stability zone from the land surface or sea floor digital image; generating a laterally extensive subsurface digital image from the seismic data that is within or below the clathrate stability zone; filtering the laterally extensive subsurface digital image to generate a pull-up digital image; generating a coarse-grained sediment digital image from the seismic data within the clathrate stability zone; spatially superimposing the coarse-grained sediment digital image and the pull-up digital image to generate a combined digital image; and determining an overlap region from the combined digital image where the pull-up digital image and the coarse-grained sediment digital image overlap, wherein the overlap region is indicative of a clathrate deposit.