504 SEDIMENTARY ENVIRONMENTS/Carbonate Shorelines and Shelves Figure Morphological classification of carbonate shelves and platforms; s l, sea level An isolated platform (sometimes also referred to as a carbonate bank, e.g Great Bahama Bank) is isolated from continental landmasses (Figure 4), and an atoll is a small isolated platform that is commonly formed over a subsiding volcano Attached and isolated platforms may have different types of morphological profile, which fundamentally affect the accumulation of sediment on the shelf A rimmed carbonate platform has a shelf margin rim or barrier, such as a reef or sand shoal, that partially isolates an inner platform or lagoon (Figure 4) A carbonate ramp is a platform or shelf that is gently inclined (