Mapping Of Shallow Karstic Aquifers By Electromagnetic Method

Earth resistivities are mapped by an EM-34 electromagnetic terrain conductivity meter in order to<br>delineate shallow Pliocene reef system which is associated with the potable water in Collier County, Florida.<br>Relationships between lithofacies, hydrogeologic properties, and geophysical signature are determined. Sixty<br>three ground water samples drawn from various depths in the area indicate the presence of a zone of wellflushed,<br>good quality water associated with coralline facies and a zone of lower permeability and relatively poor<br>quality water. The primary porosity and diagentic history of the coralline facies give them a distinctive<br>geophysical signature. This signature is the result of the destruction of the primary porosity, high karstic<br>porosity, and the presence of good quality water.