Publications

We report on the chemical analysis of water samples collected from the Taylor Mountains 1:250,000- and Dillingham D-4 1:63,360-scale quadrangles, Alaska. Reported parameters include pH, conductivity, water temperature, major cation and anion concentrations, and trace-element concentrations. We collected the samples as part of a multiyear U.S. Geological Survey project entitled "Geologic and Minera

* REE will continue to find increasing use due to their unique properties. * There is a realistic possibility around 2015-2016 of sufficient REE capacity to meet demand under conditions of healthy price competition. * REE supplies will be tight and prices high for a few years. * There is significant downside risk that newly developed mines will not perform as planned.

This report is a release of digital data from a capacitively coupled resistivity survey conducted on June 13, 2011, on the flood-protection levees surrounding the Omaha Public Power District Nebraska City power plant. The U.S. Geological Survey Crustal Geophysics and Geochemistry Science Center and the Nebraska Water Science Center performed the survey in response to a flood on the Missouri River.

At the request of the faculty of the Colorado School of Mines, Golden, Colorado, the authors prepared and presented a lecture series to the students of a graduate level advanced instrumental analysis class. The slides and text presented in this report are a compilation and condensation of this series of lectures. The purpose of this report is to present the slides and notes and to emphasize the th

No abstract available.

High-precision isotope dilution thermal ionization mass spectrometry (IDTIMS) UPb zircon and baddeleyite ages from the PX1 vertically layered mafic intrusion Fuerteventura, Canary Islands, indicate initiation of magma crystallization at 22.10 0.07 Ma. The magmatic activity lasted a minimum of 0.52 Ma. 40Ar/39Ar amphibole dating yielded ages from 21.9 0.6 to 21.8 0.3, identical within errors to the

Permeability, the ease of fluid flow through porous rocks and soils, is a fundamental but often poorly quantified component in the analysis of regional‐scale water fluxes. Permeability is difficult to quantify because it varies over more than 13 orders of magnitude and is heterogeneous and dependent on flow direction. Indeed, at the regional scale, maps of permeability only exist for soil to depth

Water samples were collected approximately every two weeks during the spring of 2010 from the Level 1 portal of the Standard Mine and from two locations on Elk Creek. The objective of the sampling was to: (1) better define the expected range and timing of variations in pH and metal concentrations in Level 1 discharge and Elk Creek during spring runoff; and (2) further evaluate possible mechanisms

The map (Plate.pdf), pamphlet (Pamphlet.pdf), and the accompanying datasets in this report provide information for 290 sites in California where asbestos occurs in natural settings, using descriptions found in the geologic literature. Data on location, mineralogy, geology, and relevant literature for each asbestos site are provided. Using the map and digital data in this report, the user can exami

The Pebble deposit in southwest Alaska (Fig. 1) contains one of the largest resources of copper and gold in the world. It includes a measured and indicated resource of 5,942 million tonnes (Mt) at 0.42% Cu, 0.35 g/t Au, and 250 ppm Mo (0.30% copper equivalent, CuEQ, cut off) and contains significant concentrations of Ag, Pd, and Re (Northern Dynasty Minerals 2011). The deposit remains open at dept

Quartz occurs in a wide range of geologic environments throughout the Earth's crust. The concentration and distribution of trace elements in quartz provide information such as temperature and other physical conditions of formation. Trace element analyses with modern electron-probe microanalysis (EPMA) instruments can achieve 99% confidence detection of ~100 ppm with fairly minimal effort for many

Whole body Zn concentrations in individuals (n = 825) from three aquatic insect taxa (mayflies Rhithrogena spp. and Drunella spp. and the caddisfly Arctopsyche grandis) were used to predict effects on populations and communities (n = 149 samples). Both mayflies accumulated significantly more Zn than the caddisfly. The presence/absence of Drunella spp. most reliably distinguished sites with low and