Kartchner Caverns, SE Arizona: A Window into Understanding and Protecting Ground Water Resources

Kartchner Caverns State Park (KCSP), located in SE Arizona, hosts caves within some low-lying, limestone hills that protrude in an enigmatic fashion through a variable blanket of younger alluvial fan deposits.  The latter flank the base of the magnificent Whetstone Mountain uplands to the west. Although this region receives on average only 13 inches of precipitation annually, the caves are wet and present magnificent cave formations, active karst-forming and hydrologic processes, and serve as a active roosting site for cave bats. The moisture budget is sustained from groundwater derived from faulted and fractured upland strata, a nearby spring, and stream runoff and infiltration across upland and rim settings, and supports a myriad of subsurface and surface ecosystems.  The caves visually and intellectually inspire and educate more than a hundred thousand visitors each year.  Proven and adaptive strategies in management and technology are tour themes.  Kartchner caverns and other caves throughout the region provide ideal laboratories and data sets for studies of mountain-front aquifers, climate change, and ecological systems.

Incision of rim deposits and differential faulting unroofed a complex basin rim aquifer.  Detailed geologic and geomorphic analyses and well data show alluvial units masking the presence of faulted and hydraulically connected bedrock and sediment strata at depth.  The caverns provide a window into architecture of a rim aquifer that shares, intercepts and sequesters groundwater on its way to basin aquifers.  High-resolution mapping is required to understand and model the behavior of complex systems in basin rim settings.  The economic and ecologic sustainability of many arid regions will depend on whether or not land planners and managers in the resource conservation and extraction industries invest in updating tools and maps to a higher level of resolution, instead of relying on outdated and/or low-resolution published information for their analysis and decision making.