Deep-water clastic settings frame major stratigraphic plays the world over. The advanced seismic interpretation tools provide prediction of accurate physical characteristics of undiscovered reservoirs, including their lithology, thickness, and porosity.The designed amplitude spectrum (DAS)-based processing tool on Full spectrum seismic may yield a remarkable stratigraphy. This study deals with the prediction of thick and porous (possibly gas-rich) litho-facies using the DAS tool on high-resolution seismal profiles within the offshore Indus Basin (OIB), SW Pakistan. The seismic and trace envelope magnitudes bound the demarcation of stratigraphic traps. The DAS processing tool on relative acoustic impedance inversion (RAI) magnitude demarcates the aggradational porous sandstone-filled reservoirs, which are encased within a transgressive non-porous shale-filled channel-levee system. The thickness predicted by band-limited seismic acoustic impedance (AI) simulation for channels, point bars, and levees is 28, 27, and 24 m, respectively. The DAS-based RAI processing on AI reservoir simulation accurately resolves the lenses of channel sandstone, point bars and levees, and confirms the channelized basin floor fans (BFFs) with an average 11, 34, 24, and 52 m thickness and a lateral extent between 10 and 25 km. The western zones have implications for basin development, which have accumulated the porous and thickest reservoir facies inside the aggradational parasequences of BFFs of Miocene sedimentary sequences. Hence, the presented scheme of exploration serves as a comparable example for exploring the hydrocarbon-bearing plays inside OIB and global deep-water depositional systems.