KISH GEOCHEMICAL STUDIES OF PUMICE 231

 

0 500 1,000 2,000 Kilometers
Explanation
——— > Major Ocean Current Active Volcanoes
= Florida Pumice Sites © Volcanic Arc

@ = = Alkalic Volcano

Figure 13. Distribution of Holocene volcanoes and major ocean currents within the Caribbean and Gulf of Mexico. Sources

of information are provided in Figure 12.

producing lahars (mudflows containing volcanic material) that
are then moved by fluvial transport to the sea. Finally, simple
erosion in the cut banks of rivers or along sea cliffs can liberate
pumice into the marine environment.

Ocean Transport

Most of the pumice artifacts from Florida are associated
with archaeological sites located along the southeastern Atlantic
coast (Figure 1). Long-term current data based upon NOAA
remote reporting drifters indicate the Gulf Stream is in close
proximity to the shoreline from Cape Canaveral to Miami
Beach. There are no strong currents that can carrv pumice

directly northward from the Lesser Antilles to the southeast
Florida shoreline. Available current information suggests that
whatever the provenance of the pumice, transport would
probably be through the Gulf of Mexico and would involve the
Florida Loop Current within the Gulf of Mexico and the Florida
Current flowing in the Florida Straits between the Florida Keys
and Cuba (Figure 13). The absence of pumice along the west
coast of Florida may be because the Florida Loop Current is
restricted to deep water, located 100 km offshore of the west
coast of Florida. An exception to the absence of the current
near land is the limited nearshore excursion of the Loop Current
along the western Panhandle of Florida (Huh et al. 1981). This
mav explain the isolated occurrences of pumice at the