ABSTRACT
The Everglades paleolake formed during the sea level low at the beginning of the Chibanian Age and at its maximum development, during this emergent time, was a deep (at least 20 m) holomictic lake that encompassed an area approximately four times the size of recent lake Okeechobee. Okeelanta sediments are known only from Glades, southern Okeechobee, westernmost Martin, Palm beach, northeasternmost Hendry, Broward, and northern Dade Counties. In the stratotype area at Okeelanta and in the Holey land, the member averages 1.5—2 m in thickness. During the preceding cooler time of the latest Calabrian, a large percentage of the Loxahatchee subsea molluscan fauna became extinct, leaving a much-diminished fauna to repopulate the ecosystems of the Belle Glade subsea. The disappearance of the organisms, and the addition of newly evolved endemic species, gives the Belle Glade fauna a distinctive impoverished appearance that can be used as a stratigraphic marker.
