Jane M. Hammarstrom

The abandoned Valzinco mine, which worked a steeply dipping Kuroko-type massive sulfide deposit in the Virginia Au-pyrite belt, contributed significant metal-laden acid-mine drainage to the Knight's Branch watershed. The host rocks were dominated by metamorphosed felsic volcanic rocks, which offered limited acid-neutralizing potential. The ores were dominated by pyrite, sphalerite...

The hydrology and quality of surface water in and around the Pike Hill Brook watershed, in Corinth, Vermont, was studied from October 2004 to December 2005 by the U.S. Geological Survey in cooperation with the U.S. Environmental Protection Agency (USEPA). Pike Hill was mined intermittently for copper from 1847 to 1919 and the site is known to be contributing trace elements and acidity to...

North-central and northeast Nevada contains numerous large plutons and smaller stocks but also contains many small, shallowly emplaced intrusive bodies, including dikes, sills, and intrusive lava dome complexes. Decades of geologic investigations in the study area demonstrate that many ore deposits, representing diverse ore deposit types, are spatially, and probably temporally and...

The Red Mountain volcanogenic massive sulfide (VMS) deposit exhibits well-constrained examples of acid-generating, metal-leaching, metal-precipitation, and self-mitigation (via co-precipitation, dilution, and neutralization) processes that occur in an undisturbed natural setting, a rare occurrence in North America. The unmined pyrite-rich deposit displays a remarkable environmental...

The unmined, pyrite-rich Red Mountain (Dry Creek) deposit displays a remarkable environmental footprint of natural acid generation, high metal and exceedingly high rare earth element (REE) concentrations in surface waters. The volcanogenic massive sulphide deposit exhibits well-constrained examples of acid-generating, metal-leaching, metal-precipitation and self-mitigation (via co...

The Virginia gold-pyrite belt, part of the central Virginia volcanic-plutonic belt, hosts numerous abandoned metal mines. The belt extends from about 50 km south of Washington, D.C., for approximately 175 km to the southwest into central Virginia. The rocks that comprise the belt include metamorphosed volcanic and clastic (noncarbonate) sedimentary rocks that were originally deposited...