USGS Home
Contact USGS
Search USGS

Geochemistry (continued) 2

Project Home Geology Geophysics Remote Sensing Geochemistry Publications Gallery

Geochemical Studies

Initial geochemical studies focused on mineralized regions of the Patagonia Mountains, northeast of Nogales. An unexploited, heavily explored, buried porphyry copper system at Red Mountain provides baseline geochemical information with potential for comparison to exploited porphyry copper deposits in the Sierrita Mountains south of Tucson. The Patagonia Mountains also hosts many small base metal-rich precious metal deposits which source acid drainage, as well as sulfide-rich skarn deposits. The study involved analysis of various media: surface and mine-drainage fluids, ground waters, fresh and altered rocks, pristine and secondary minerals.

Methods

• Fluid cation chemistry, including a suite of trace elements, by high-precision ICP-MS. Information about the ICP-MS facilities.
• Fluid anion chemistry by ion chromatography
• Major element chemistry of rocks and minerals by electron microprobe.
• Mineral textural investigations by scanning electron microscope. Information about the Denver Microbeam Laboratory.
• Trace and ultra-trace element analyses of minerals by laser-ablation ICP-MS (see ICP-MS URL address)
• Fluid and solid phase stable isotope analysis (H, O, and S isotopes by gas mass spectrometry).

More Geochemistry