The geochemistry of water-filled sinkholes at Bitter Lake National Wildlife Refuge, Roswell, NM : implications for hydrochemical evolution and trophic support

This study provides a hydrochemical baseline survey of water-filled sinkholes at Bitter Lake Nation Wildlife Refuge (Roswell, NM). Water samples from 10 representative sinkholes taken at 1.0m increments were analyzed for major ions, stable isotopes [18O, D], and dissolved gases. Sinkholes are surface features at a constant head boundary found at the discharge region for the Roswell Artesian Basin, recharged by upwardly flowing artesian springs. Constant head is confirmed by a lack of measured change in depth during two sampling sessions (October 2008, May 2009), low relief (