Publications

A hydrogeochemical study using high resolution ICP-MS was undertaken at the giant Pebble porphyry Cu-Au-Mo deposit and surrounding mineral occurrences. Surface water and groundwater samples from regional background and the deposit area were collected at 168 sites. Rigorous quality control reveals impressive results at low nanogram per litre (ng/l) levels. Sites with pH values below 5.1...

The element bromine is found principally as a dissolved species in seawater, evaporitic (salt) lakes and underground brines associated with petroleum deposits. Seawater contains about 65 parts per million of bromine or an estimated 100 Tt (110 trillion st). In the Middle East, the highly saline waters of the Dead Sea are estimated to contain 1 Gt (1.1billion st) of bromine. Bromine is...

Common clay is a natural, fine-grained material composed of hydrous aluminum silicates. Shale is a laminated sedimentary rock formed by the consolidation of clay, mud and/or silt.

World fluorspar demand continued to show signs of recovery from 2008-2009 recession. In 2011, nearly all fluorspar (CaF2) consumed in the United States was imported. Hastie Mining and Trucking Co. produced some fluorspar as a byproduct from its limestone quarry operations in Illinois. In addition, a small amount of usable synthetic fluorspar was produced from industrial waste streams.

Neogene (Miocene–Pliocene) sedimentary rocks of the northeastern Sierra Nevada were deposited in small basins that formed in response to volcanic and tectonic activity along the eastern margin of the Sierra. These strata record an early phase (ca. 11–10 Ma) of extension and rapid sedimentation of boulder conglomerates and debrites deposited on alluvial fans, followed by fluvio-lacustrine

Manganese is a silver-colored metal resembling iron and often found in conjunction with iron. The earliest-known human use of manganese compounds was in the Stone Age, when early humans used manganese dioxide as pigments in cave paintings. In ancient Rome and Egypt, people started using it to color or remove the color from glass - a practice that continued to modern times. Today...

Magnesium is the eighthmost abundant element in Earth’s crust, and the second-most abundant metal ion in seawater. Although magnesium is found in more than 60 minerals, only brucite, dolomite, magnesite and carnallite are commercially important for their magnesium content. Magnesium and its compounds also are recovered from seawater, brines found in lakes and wells, and bitterns (salts).

The framework of Quaternary faults in Alaska remains poorly constrained. Recent studies in the Alaska Range north of the Denali fault add significantly to the recognition of Quaternary deformation in this active orogen. Faults and folds active during the Quaternary occur over a length of ∼500 km along the northern flank of the Alaska Range, extending from Mount McKinley (Denali) eastward...

Demand for the rare earth elements (REE, lanthanide elements) is estimated to be increasing at a rate of about 8% per year due to increasing applications in consumer products, computers, automobiles, aircraft, and other advanced technology products. Much of this demand growth is driven by new technologies that increase energy efficiency and substitute away from fossil fuels. Production...

In 1996, at the request of the Government of the Islamic Republic of Mauritania, a team of U.S. Geological Survey (USGS) scientists produced a strategic plan for the acquisition, improvement and modernization of multidisciplinary sets of data to support the growth of the Mauritanian minerals sector and to highlight the geological and mineral exploration potential of the country. In 1999...

In 1996, at the request of the Government of the Islamic Republic of Mauritania, a team of U.S. Geological Survey (USGS) scientists produced a strategic plan for the acquisition, improvement and modernization of multidisciplinary sets of data to support the growth of the Mauritanian minerals sector and to highlight the geological and mineral exploration potential of the country. In 1999...

In 1996, at the request of the Government of the Islamic Republic of Mauritania, a team of U.S. Geological Survey (USGS) scientists produced a strategic plan for the acquisition, improvement and modernization of multidisciplinary sets of data to support the growth of the Mauritanian minerals sector and to highlight the geological and mineral exploration potential of the country. In 1999...