Scientific Investigations Report 2005-5232 The carbonate-rock
aquifer of the Great Basin is named for the thick sequence of
Paleozoic limestone and dolomite with lesser amounts of shale,
sandstone, and quartzite. It lies primarily in the eastern half
of the Great Basin and includes areas of eastern Nevada and
western Utah as well as the Death Valley area of California and
small parts of Arizona and Idaho. The carbonate-rock aquifer is
contained within the Basin and Range Principal Aquifer, one of
16 principal aquifers selected for study by the U.S. Geological
Survey’s National Water- Quality Assessment Program. Water
samples from 30 ground-water sites (20 in Nevada and 10 in Utah)
were collected in the summer of 2003 and analyzed for major
anions and cations, nutrients, trace elements, dissolved organic
carbon, volatile organic compounds (VOCs), pesticides, radon,
and microbiology. Water samples from selected sites also were
analyzed for the isotopes oxygen-18, deuterium, and tritium to
determine recharge sou