Scope and Methods
The Greater Green River Basin is home to several endemic plant species and endangered animals, notably sage grouse and pygmy rabbit. The Green River Formation that characterizes much of the basin also hosts thick sequences of organic carbon-rich shale (oil shale), extractable pockets of natural gas, and bedded trona (Na3(CO3)(HCO3)•2H2O), the extractions or minings of which can mobilize elements that could potentially affect ecosystem function and processes in the basin.
In an ongoing attempt to develop methods for assessing element mobility in the basin, USGS obtained commercial chemical analyses from XRAL Laboratory, Canada, for use in analyzing major elements with inductively coupled plasma-atomic emission spectrometry. Minor and trace elements were then analyzed with mass spectrometry. Soils were extracted by using a method (saturated paste extracts) that best simulates the type of weathering that occurs in a semi-arid climate characteristic of the study area. Filtered and acidified saturation paste extracts were analyzed by inductive coupled plasma-atomic emission spectrometry (major cations), ion chromatography (major anions), titration (alkalinity), and inductive coupled plasma mass spectrometry (minor and trace elements).