Groundwater(40 slides) $80

Groundwater trapped in porous rock in the crust is one of our most important resources. These slides show mechanisms of transport, aquifers, water tables, limestone cave formation, geysers, major aquifers and hot springs in the USA , karst topography in Florida, limestone sinkholes in Texas and Arizona and subsidence of cultivated land in Arizona due to groundwater withdrawal.

Copyright 1999 by Pan Terra Inc., PO Box 556, Hill City, SD, USA 57745.

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