Satellite imagery and an extensive set of water-depth measurements have been used to map and critically evaluate the magnitude and patterns of bathymetry across Great Bahama Bank. Descriptions of previously collected sediment samples were combined with satellite imagery to map and refine the interpreted distribution of surficial carbonate sediments (depositional facies). Data reveal that 60% of Great Bahama Bank lies in 5 m or less of water. The deep portion occurs mainly in a generally east-west trending area in the southern portion of the platform. The re-evaluation of the facies reveals that Great Bahama Bank is essentially a very grainy platform with muddier accumulations primarily in the lee of Andros Island. This area of Great Bahama Bank also experiences currents related to an excursion of the Florida Current onto the platform top; possibly enhancing sediment mud production through the generation of whitings. Sediment equivalents to mudstones, wackestones and mud-rich packstones cover 8%, 5% and 14%, respectively, of the platform top, whereas sediment equivalents to mud-poor packstones, grainstones and rudstones account for 20%, 45% and 3% of the surface area. Boundstones (reefs) were not specifically mapped in this study due to the resolution of the mapping. There is a poor relationship between the occurrence of the depositional texture and water depth, in that the grainier sediment types are abundant across the full range of water depths. The most abrupt lateral facies changes portrayed on the facies maps are observed leeward of islands, areas which also hold the highest diversity in facies type. The majority of the islands on the platform align with the north-west/south-east strike of the platform margin and these islands, in turn, exert control on the shape and orientation of facies belts that develop in proximity to them. For this reason, regions of the platform that contain principal islands host facies belts that align with the principal axis of the platform, whereas for regions lacking islands, the facies belts adopt an eastwest trend consistent with prevailing winds and currents. There is a clear trend that the wide southern portion of the platform hosts the most continuous expanses of grain-rich sediments.

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Facies relations determined from outcrop studies have been used in conjunction with subsurface data to better understand the geologic evolution, depositional facies, and diagenesis of the Capitan shelf margin. These studies have centered on a 2400 ft (731 m) portion of a 4800 ft (1463 m) continuous core from the Gulf PDB-04 research well that is located in Eddy County, New Mexico, at the northern end of the Delaware Basin. The evolution of the Capitan shelf and margin was examined after (a) the establishment of time lines for shelf-to-basin correlations in the Late Guadalupian and (b) the confirmation of the stratigraphic units penetrated in the PDB-04 well. Subsurface and outcrop data revealed that the evolution of the 2.5 m.y. duration Capitan shelf margin occurred in two major growth phases: a 1.5 m.y. duration phase during Seven Rivers time when over 80% of the total progradation, over half of the total aggradation, deposition of thick carbonate debris units on the slope and basin margin, and influx of over 60% of the total siliciclastics of the Bell Canyon Formation occurred. A subsequent, 1.0 m.y. growth phase during Yates and Tansill time is dominated by aggradation, steepening of the margin, and corresponds with abundant clastic deposition on the shelf. Maximum progradation of up to 12 miles (19 km) occurred along the northern rim of the basin, where progradation rates in excess of 7500 µm/year are measured. Detailed shelf-to-basin correlations have revealed that three major processes were responsible for the profound progradation and differentiation of Capitan growth into two major phases: (a) fluctuations of sea level, (b) maximum emplacement of allochthonous carbonate debris along the basin margin during Seven Rivers time, and (c) that abundant siliciclastics bypassed the actively prograding shelf margin and were an important foundation for the progradation. Because the Capitan was a deeply submerged reef during most of its growth, progradation occurred during both