|MadSci Network: Environment & Ecology|
I'm not sure where the deepest sink hole in the U.S. is, but it is probably in a area of limestone or dolomite (carbonate rocks). Carbonate rocks dissolve when water percolates through fractures in them to form caverns. To assist you in locate various sinkholes... and possibly some candidates for deepest in the U.S. and other places in the world, I found some internet links that you can explore: WILD CAVE TOURS http://www.utexas.edu/depts/tnhc/.www/tss/wildtours.htm The deepest cenote or sinkhole in the Maya World http://www.mayanstar.com.mx/priadven.html Deep Sinkhole in Turkey http://www.naturekey.com/articles/intros/professionalcaves.html Harwood's Hole, Takaka NZ http://www-svr.eng.cam.ac.uk/~jccc/Egallery/cave/harwood3.html Speleological Potential Of Turkey http://www.turkey.org/groupe/e Good luck in exploring the internet in your quest for sink holes!
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