This seminar will discuss regional and local scale geomorphic features of
the eastern portions of Miami-Dade, Broward, Palm Beach, and Martin Counties
as interpreted from color shaded relief maps of high resolution digital
elevation models (DEM). The DEMs were derived from airborne LIDAR elevations
collected from 2000-2004 by Florida Internional University, and the US Army
Corps of Engineers. These data sets were gridded at resolutions of 5 or 10
ft for large scale (local) interpretation and also were mosaiced and
subaveraged to produce a 100 ft resolution DEM for regional interpretation.
Regional scale features on the 100 ft DEM are similar to those seen on USGS
NED 1" DEMs but generally show more detail than those topo map derived
products. Regional topographic features related to the Atlantic Coastal
Ridge show distinct geomorphic changes at the approximate latitude of
Pompono Beach, FL. This roughly coincides with changes in the late
Pleistocene bedrock geology with the Miami Fm. to the south and the
Anastacia Fm. to the north and these geomorphic changes probably reflect
latitudinal changes in wave energy associated with the deposition of these
units. At the local scale, the 5 ft DEMs clearly show younger karst and
erosional features.