Blue Holes in Bahamas: Repositories of Climate,Anthropogenic, and Archaeological Changes over the Past 300 000 Years

摘要

Blues Holes in the Bahamas are solution collapse features which formed in the Bahamas during the repeated sea-level changes which have occurred over the past 2 million years. Not only were these Blue Holes repositories of well preserved organisms which found their ways into their anoxic waters and therefore have been very well preserved, but the sediments also record a legacy of anthropogenic activities in the area during the Pleistocene. Perhaps the most intriguing aspects of the Blue Holes are the multiple generations of stalagmites which record variations in sea-level, temperature, and precipitation during the numerous sea-level low stands. During these periods the caves were located within the vadose zone and freshwater leached the overlying carbonate. As the waters trickled into the caves they rapidly degassed forming both stalactites and stalagmites. Using uranium series dating these materials have been accurately dated and the variations in the stable isotopes and trace elements analyzed.