Fracture caves
Many Quaternary carbonate platforms are steep sided. Such steep slopes are prone to mechanical failure, and that may be a major part of how carbonate platform margins are modified through time (Mullins and Hine, 1989). Fractures parallel to bank margins are common in the Bahamas (Daugherty et al., 1987; Carew and Mylroie, 1989; Carew et al., 1992). These fractures are commonlyh the site of cave systems with extensive vertical and linear development (Palmer, 1986). Such fracture caves may also represent a means by which Neptunian dikes and fissure fills are developed (Smart et al., 1988b). Fracture caves are not dissolutional in origin; however, once they are formed, they act as pathways for water flow into and/or out of the carbonate platform. While they may form without the platform becoming emergent, platform emergence, with subsequent dissolution at the discharging margin of the fresh water lens, may help promote overall rock weakness that leads to bank-margin collapse and fracture development. During glacio-eustatic sea level lowstands, loss of buoyant support that was provided by the water during the highstand is probably a contributing factor in the fracture development.