Since early 2010, the Gulf of Mexico Miocene CO2 Site Characterization Mega Transect study has evaluated storage capacity of the Miocene section of offshore Submerged Lands (State Waters) of the State of Texas, exclusive of inland bays and waterways with emphasis on the upper Texas coast. Availability of extensive geologic datasets (wireline well logs, micropaleontology, rock data, regional 2D and conventional 3D, etc.) from historic and recent petroleum industry exploration and production activity have greatly enhanced the regional and site specific evaluations of the study area. One of the important factors affecting storage capacity is the capability of confining systems to sequester injected CO2 for required time periods. One way to assess such capability is to use the natural petroleum system as an analog for a future engineered system and evaluate the ability of the former to trap hydrocarbons, especially the light fraction (natural gas). One innovative tool that the current study has used for this objective has been a P-Cable high-resolution 3D (HR3D) seismic acquisition system purchased specifically for this purpose. HR3D seismic surveys encompass the shallowest 0 to 1500+ milliseconds of two-way-time, a section that is poorly or not at all characterized by conventional 3D seismic data. During the 2013-2014 fiscal year, two HR3D surveys were successfully acquired from distinct locations approximately 75 Km’s apart. Processed results from the 2013 survey show very high resolution data detailing fine-scale geomorphologic and natural fluid-system features that may provide critical information about the Miocene and younger confining system and thus capacity.