Relationships between the groundwaters of Ash Meadows, Death Valley, Pahranagat Valley and the Nevada Test Site based on statistical analysis and modeling of trace element data

Sara Michelle Cox, University of Nevada, Las Vegas


Relationships between the groundwaters of the Nevada Test Site, Ash Meadows, Pahranagat, and Death Valley have been studied by many people over many years. Using hydrogeochemical data from these areas (sampled and analyzed by the Harry Reid Center for Environmental Studies) hydrologic subbasins were classified on the basis of trace element concentrations and compare these to previous classification systems. In addition, previously suggested flow relationships were examined on the basis of trace element concentrations, in particular those elements which are thought to behave conservatively in oxidizing environments. These efforts were made with the aid of statistical analyses such as principal component analysis and contouring within ARC/INFO (a geographic information system). The spring and well water chemistry data includes major ion and trace element chemistry and was obtained from the Harry Reid Center for Environmental Studies at UNLV. In most analyses only trace elements were examined. Results of principal component analysis yielded logical results that reflect differences in geology and location. Perched waters on the Nevada Test Site have the most unique chemistries. Waters from the Furnace Creek region of Death Valley, Ash Meadows, and Pahranagat Valley seem to have many similarities with respect to trace elements. Contour modeling reveals that at least three processes or parameters control the behaviour of trace elements within the study area.