Origin and evolution of the Candlelight Reef-Sand Clay system, St. Croix.

Candlelight reef is the buttressing western terminus of the northeastern St. Croix reef system, caused by a combination of paleotopography and longshore drift which created a stable pile of detrital material at this position. Reef colonization proceeded eastward along the former slope break on the limestone terrace; turbid gyres along the eastern margin of the former Southgate drainage prevented further westward colonization. The presence of detrital cobbles in Sand Cay and Candlelight reef is explained by this model. An unconformity between underlying fine-grained quartzose rocks and overlying carbonates, need represent only an eustatic sea level rise rather than any fundamental tectonic event.-from Author