searchable PDF - Association for Mexican Cave Studies

Beach and Supra-tidal Zone, the I\orthwesternCoastal Plain, the Northeastern Coastal Plain, and theEastern Block Fault District. The first and last ofthese are of limited speleological interest. The o~hertwo subdivisions exhibit quite different morphology,but are so similar faunally that they are here treatedas one unit. The northwestern Coastal Plain is characterizedby very low relief (usually less than twometers locally), little soil, Hat-lying limestont' anddolomite, and the absence of deep caves and cenotes.The water level is ~enerally less than 10 mcters helowthe surface. The Northeastern Coastal Plain has muchgreater relief and ex tensive karst development. Theterrain is largely characterized by the presence ofnumerous cenotes, some more than 30 meters deep.This is best seen in the vicinity of Chichen Itza. Inextreme northwestern Yucatan and adjacent QuintanaRoo, the terrain is more rolling with large shallowdolinas and few cenotes. At the highest part ofthe plain, near Coba in Quintana Roo. cenotes an:generally absent and several lakes may be found.Along the Caribbean coast in ()uintana Hoo cenotesare generally shallow and water occurs less than 10meters below the surfa