Florida Geological Survey - Geology Topics
The Miami Limestone (formerly the Miami Oolite) is a
(see time scale) marine limestone. It occurs at
or near the surface in southeastern peninsular Florida from Palm Beach
County to Dade and Monroe Counties and in the keys from Big Pine Key to the
Marquesas Keys. The Miami Limestone consists of two facies: an oolitic
facies and a bryozoan facies. The oolitic facies consists of white to
orangish gray, oolitic limestone with scattered concentrations of fossils.
Ooliths are small rounded grains so named because they look like fish eggs.
Ooliths are formed by the deposition of layers of calcite around tiny
particles, such as sand grains or shell fragments. The bryozoan facies
consists of white to orangish gray, sandy, fossiliferous limestone. Beds of
quartz sand and limey sandstones may also be present. Fossils present
include mollusks, bryozoans, and corals. An excellent exposure is observable
at Alice Wainright Park, in Coral Gables, Dade County.