Philip Verplanck - Academia.edu (original) (raw)

Papers by Philip Verplanck

Open-file report /, 2007

Mine drainage and underground water samples were collected for analysis of inorganic solutes as p... more Mine drainage and underground water samples were collected for analysis of inorganic solutes as part of a 1-year, hydrogeologic investigation of the Standard Mine and vicinity. The U.S. Environmental Protection Agency has listed the Standard Mine in the Elk Creek drainage near Crested Butte, Colorado, as a Superfund Site because discharge from the Standard Mine enters Elk Creek, contributing dissolved and suspended loads of zinc, cadmium, copper, and other metals to Coal Creek, which is the primary drinking-water supply for the town of Crested Butte. Water analyses are reported for mine-effluent samples from Levels 1 and 5 of the Standard Mine, underground samples from Levels 3 and 5 of the Standard Mine, mine effluent from an adit located on the Elk Lode, and two spring samples that emerged from waste-rock material below Level 5 of the Standard Mine and the adit located on the Elk Lode. Reported analyses include field parameters (pH, specific conductance, water temperature, dissolved oxygen, and redox potential) and major constituents and trace elements.

Chemical Geology, Aug 1, 2019

Aluminum precipitates control the hydrochemistry and mineralogy of a broad variety of environment... more Aluminum precipitates control the hydrochemistry and mineralogy of a broad variety of environments on Earth (e.g., acid mine drainage, AMD, coastal wetlands, boreal and alpine streams, tropical acid sulfate soils, laterites and bauxites, …). However, the geochemical and mineralogical processes controlling Al (and other associated metals and metalloids) transport and removal in those environments are not fully understood. The geochemical system of Paradise Portal (Colorado, USA) comprises sulfate-rich mildly acidic waters, the hydrochemistry of which is directly controlled by the massive precipitation of hydrobasaluminite Al 4 (SO 4)(OH) 10 •12-36H 2 O. Three connected but discernible aluminum precipitation stages were identified and described: 1) nanoparticle formation and size decrease along the creek, 2) hydrobasaluminite neoformation on the riverbed, and 3) precipitate accretion and accumulation on the riverbed leading to Al and Fe banded formations. The co-occurrence of Al and Si in the system was observed, recording significant amounts of Si accompanying the three different components of the system (i.e., nanoparticles and fresh and aged Al-precipitates). Also, abrupt and minor changes in the sedimentary record were described and proposed to be the response of the system to seasonal and interannual changes in AMD chemistry. Concerning the mobility of other metals and metalloids, P, Th, V, W, Ti and B showed a tendency to be preferentially incorporated into hydrobasaluminite, while others like Be, As, Se or Ba tend to remain dissolved in the water.

Open-file report /, 2011

The rare earth elements (REEs) are not as rare in nature as their name implies, but economic depo... more The rare earth elements (REEs) are not as rare in nature as their name implies, but economic deposits with these elements are not common and few deposits have been large producers. In the past 25 years, demand for REEs has increased dramatically because of their wide and diverse use in hightechnology applications. Yet, presently the global production and supply of REEs come from only a few sources. China produces more than 95 percent of the world's supply of REEs. Because of China's decision to restrict exports of these elements, the price of REEs has increased and industrial countries are concerned about supply shortages (Tse, 2011). As a result, understanding the distribution and origin of REE deposits, and identifying and quantifying our nation's REE resources have become priorities. Carbonatite and alkaline intrusive complexes, as well as their weathering products, are the primary sources of REEs (Long and others, 2010). The general mineral deposit model summarized here is part of an effort by the U.S. Geological Survey's Mineral Resources Program to update existing models and develop new descriptive mineral deposit models to supplement previously published models for use in mineral-resource and mineral-environmental assessments. We are discussing carbonatite and alkaline intrusion-related REE deposits together because of their spatial association, common enrichment in incompatible elements, and similarities in genesis. A wide variety of commodities have been exploited from carbonatites and alkaline igneous rocks, such as rare earth elements, niobium, phosphate, titanium, vermiculite, barite, fluorite, copper, calcite, and zirconium. Other enrichments include manganese, strontium, tantalum, thorium, vanadium, and uranium. The REEs are defined as the elements from lanthanum to lutetium (atomic numbers 57 to 71) and yttrium (atomic number 39). Yttrium is typically included as a REE with the "lanthanides" (lanthanum to lutetium) because of its similarity in chemical properties and applications. The elements from lanthanum to gadolinium are referred to as light REEs (LREEs); the elements from terbium to lutetium are referred to as heavy REEs (HREEs). Overall, the REEs have similar geochemical properties, because they all form stable 3 + ions of similar size. Slight differences in their geochemical behavior occur because, with increasing atomic number, there is a steady decrease in ionic size. Cerium and europium can exist in oxidation states other than 3 + , with cerium also occurring as 4 + and europium as 2 +. Yttrium only occurs as 3 + and has an ionic radius similar to holmium (1.019 compared to 1.015 angstroms, respectively); thus, yttrium is grouped with the HREEs. Although the geochemical properties of REEs are similar, their metallurgical, chemical, catalytic, electrical, magnetic, and optical properties vary, and these unique properties and differences have lead to their prominence in a variety of emerging technologies. Whereas no REE deposit models have been published, some deposits are described in the literature. In particular, extensive work has been done on the petrology of carbonatites and alkaline intrusive complexes. Understanding the petrology and petrogenesis of carbonatites and alkaline

Fact sheet /, 2014

Until recently, the rare-earth elements (REEs) were familiar to a relatively small number of peop... more Until recently, the rare-earth elements (REEs) were familiar to a relatively small number of people, such as chemists, geologists, specialized materials scientists, and engineers. In the 21st century, the REEs have gained visibility through many media outlets because (1) the public has recognized the critical, specialized properties that REEs contribute to modern technology, as well as (2) China's dominance in production and supply of the REEs and (3) international dependence on China for the majority of the world's REE supply. Since the late 1990s, China has provided 85-95 percent of the world's REEs. In 2010, China announced their intention to reduce REE exports. During this timeframe, REE use increased substantially. REEs are used as components in high technology devices, including smart phones, digital cameras, computer hard disks, fluorescent and light-emitting-diode (LED) lights, flat screen televisions, computer monitors, and electronic displays. Large quantities of some REEs are used in clean energy and defense technologies. Because of the many important uses of REEs, nations dependent on new technologies, such as Japan, the United States, and members of the European Union, reacted with great concern to China's intent to reduce its REE exports. Consequently, exploration activities intent on discovering economic deposits of REEs and bringing them into production have increased.

Applied Geochemistry, Aug 1, 2004

Ferrous iron rapidly oxidizes to Fe (III) and precipitates as hydrous Fe (III) oxides in acid min... more Ferrous iron rapidly oxidizes to Fe (III) and precipitates as hydrous Fe (III) oxides in acid mine waters. This study examines the effect of Fe precipitation on the rare earth element (REE) geochemistry of acid mine waters to determine the pH range over which REEs behave conservatively and the range over which attenuation and fractionation occur. Two field studies were designed to investigate REE attenuation during Fe oxidation in acidic, alpine surface waters. To complement these field studies, a suite of six acid mine waters with a pH range from 1.6 to 6.1 were collected and allowed to oxidize in the laboratory at ambient conditions to determine the partitioning of REEs during Fe oxidation and precipitation. Results from field experiments document that even with substantial Fe oxidation, the REEs remain dissolved in acid, sulfate waters with pH below 5.1. Between pH 5.1 and 6.6 the REEs partitioned to the solid phases in the water column, and heavy REEs were preferentially removed compared to light REEs. Laboratory experiments corroborated field data with the most solid-phase partitioning occurring in the waters with the highest pH.

Geochimica et Cosmochimica Acta Supplement, Jun 1, 2009

article i nfo Article history: Accepted 25 May 2009 With the increased importance of water resour... more article i nfo Article history: Accepted 25 May 2009 With the increased importance of water resources in the western United States and many areas worldwide, the remediation of impacts from historical mining becomes ever more important. A possible process of making decisions about remediation for a catchment might include identification of principal sources of metals in the catchment, classification of the sources as natural or anthropogenic, and simulations to evaluate different options for removal of anthropogenic sources. The application of this process is based on understanding the pre-mining conditions in the catchment, so that remediation goals appropriately correct for the impacts of mining. A field experiment in Redwell Basin, Colorado, provided a setting to demonstrate this process and to evaluate pre-mining concentrations through reactive solute-transport modeling. The field experiment provided spatially detailed stream and inflow samples that were the basis for model calibration. Only two inflows along the study reach were affected by mining or mine exploration. To simulate pre-mining conditions, these inflows were removed from the model calibration; the result was a simulation of the stream with all the non-mining inputs. At a point downstream from the two mining inflows, the simulated pre- mining pH would have been 5.1, up from the measured 3.8. At the higher pH, the streambed likely would have been coated with Al precipitate. Simulated pre-mining Zn and Cu would have been 1300 µg/L and 18 µg/ L, lower than the measured concentrations of 3340 and 93 µg/L. Despite these changes, the pre-mining conditions would not have met aquatic-life standards. Published by Elsevier B.V.

Science of The Total Environment

Rare Earth and Critical Elements in Ore Deposits, 2016

Open-File Report, 2003

Regional and Local Geology……………………………………… Methods of Study………………………………………………………….. Water-Chemistr... more Regional and Local Geology……………………………………… Methods of Study………………………………………………………….. Water-Chemistry Sampling……………………………………….. 6 Water-Chemistry Analyses……………………………………….. Quality Assurance………………………………………………………… Chemical Data……………………………………………………………. References Cited………………………………………………………… 39 FIGURES 1. Map of Alaska with location of study area ……………………….... 2. Topographic map of Ester Dome, Alaska with sampling site locations…………………………………………………………….. 3. Comparison of analytical results by ICP-AES and ICP-MS for Ba, Mn, and Sr. …………………………………………………. TABLES 1. Sampling site locations…………………………………………... 2. Methods of analysis and detection limits………………….………. 8 3. Dissolved organic carbon determinations ………………………… 4. 34 S and 18 O isotope determinations………………………………... 10 5. Results of water analyses of Ester Dome, Alaska………………….

Scientific Investigations Report, 2006

Cover photo: Streambed cobbles from the Red River near Capulin Canyon, New Mexico. These cobbles ... more Cover photo: Streambed cobbles from the Red River near Capulin Canyon, New Mexico. These cobbles have been turned over to show that iron oxyhydroxide precipitates (ochre color) form below the streambed and aluminum oxyhydroxide precipitates (white) form in the water column above the streambed. The difference occurs because the pH in the stream is greater than 7.0 and the pH in the streambed is less than 5.0. The visible chemical differences indicate that acidic ground water is entering the stream.

Open-file report /, 2002

Sixty-seven water analyses are reported for samples collected from 44 hot springs and their overf... more Sixty-seven water analyses are reported for samples collected from 44 hot springs and their overflow drainages and two ambient-temperature acid streams in Yellowstone National Park (YNP) during 1990-2000. Thirty-seven analyses are reported for 1999, 18 for June of 2000, and 12 for September of 2000. These water samples were collected and analyzed as part of research investigations in YNP on microbially mediated sulfur oxidation in stream water, arsenic and sulfur redox speciation in hot springs, and chemical changes in overflow drainages that affect major ions, redox species, and trace elements. Most samples were collected from sources in the Norris Geyser Basin. Two ambient-temperature acidic stream systems, Alluvium and Columbine Creeks and their tributaries in Brimstone Basin, were studied in detail. Analyses were performed at or near the sampling site, in an on-site mobile laboratory truck, or later in a USGS laboratory, depending on stability of the constituent and whether or not it could be preserved effectively. Water temperature, specific conductance, pH, Eh, dissolved oxygen (D.O.), and dissolved H 2 S were determined on-site at the time of sampling. Alkalinity, acidity, and F were determined within a few days of sample collection by titration with acid, titration with base, and ion-selective electrode or ion chromatography (IC), respectively. Concentrations of S 2 O 3 and S x O 6 were determined as soon as possible (minutes to hours later) by IC. Concentrations of Br, Cl, NH 4 , NO 2 , NO 3 , SO 4 , Fe(II), and Fe(total) were determined within a few days of sample collection. Densities were determined later in the USGS laboratory. Concentrations of Li and K were determined by flame atomic absorption spectrometry.

Sources and hydrologic flow paths need to be determined to evaluate remedial options in miningaff... more Sources and hydrologic flow paths need to be determined to evaluate remedial options in miningaffected basins. The 87Sr/86Sr ratios of a suite of water and rock samples from the Middle Fork Mineral Creek basin in the upper Animas River watershed, Colorado, were determined to investigate their possible use as a geochemical tracer for sources and flow paths. Leaching experiments were performed on the dominant lithologies in the study area to determine the more easily weathered constituents, including strontium. Variations in whole-rock 87Sr/86Sr ratios correlate with lithology and hydrothermal alteration intensity. For a given alteration assemblage, the porphyritic quartz monzonite has a lower 87Sr/86Sr ratio than the surrounding San Juan Volcanics, and for a given lithology the 87Sr/86Sr ratio is lower for propylitically altered rocks than for quartz-sericite-pyrite altered rocks. The 87 Sr/86Sr ratios of waters draining different lithologies and alteration assemblages have correspondingly different strontium isotopic ratios. The age of magmatism and alteration is relatively young (28-25 million years) compared to the half-life of 87Rb, so that the isotopic variation is not great enough to determine mixing ratios for waters derived from multiple sources. In this study area, mine drainage does not have a unique strontium isotopic composition because the mined areas do not have a strontium isotopic composition distinctly different from the unmined, mineralized host rocks.

Ore Geology Reviews, Jul 1, 2022

Stream water and sediment toxicity to aquatic insects were quantified from central Colorado catch... more Stream water and sediment toxicity to aquatic insects were quantified from central Colorado catchments to distinguish the effect of geologic processes which result in high background metals concentrations from historical mining. Our sampling design targeted small catchments underlain by rocks of a single lithology, which allowed the development of biological and geochemical baselines without the complication of multiple rock types exposed in the catchment. By accounting for geologic sources of metals to the environment, we were able to distinguish between the environmental effects caused by mining and the weathering of different mineralized areas. Elevated metal concentrations in water and sediment were not restricted to mined catchments. Impairment of aquatic communities also occurred in unmined catchments influenced by Schmidt is a Mendenhall post doctoral fellow and research ecologist,

2014 AGU Fall Meeting, Dec 15, 2014

Open-file report /, 2008

As part of a multidisciplinary project to determine the processes that control groundwater chemis... more As part of a multidisciplinary project to determine the processes that control groundwater chemistry and flow in mineralized alpine environments, ground-and surface-water samples from Handcart Gulch, Colorado were collected for analysis of inorganic solutes and water and dissolved sulfate stable isotopes in selected samples. The primary aim of this study was to document variations in groundwater chemistry in Handcart Gulch and to identify changes in water chemistry along the receiving stream of Handcart Gulch. Water analyses are reported for groundwater samples collected from 12 wells in Handcart Gulch, Colorado. Samples were collected between August 2003 and October 2005. Water analyses for surface-water samples are reported for 50 samples collected from Handcart Gulch and its inflows during a low-flow tracer injection on August 6, 2003. In addition, water analyses are reported for three other Handcart Gulch stream samples collected in September 2005 and March 2006. Reported analyses include field parameters (pH, specific conductance, temperature, dissolved oxygen, and Eh), major and trace constituents, oxygen and hydrogen isotopic composition of water and oxygen and sulfur isotopic composition of dissolved sulfate. Groundwater samples from this study are Ca-SO 4 type and range in pH from 2.5 to 6.8. Most of the samples (75 percent) have pH values between 3.3 and 4.3. Surface water samples are also Ca-SO 4 type and have a narrower range in pH (2.7-4.0). Groundand surface-water samples vary from relatively dilute (specific conductance of 68 μS/cm) to concentrated (specific conductance of 2,000 μS/cm).

Contributions to Mineralogy and Petrology, 2016

of 36.441 ± 0.020 Ma (Cueva Tuff), 36.259 ± 0.016 Ma (Achenback Park tuff), and 36.215 ± 0.016 Ma... more of 36.441 ± 0.020 Ma (Cueva Tuff), 36.259 ± 0.016 Ma (Achenback Park tuff), and 36.215 ± 0.016 Ma (Squaw Mountain tuff). An alkali feldspar granite, which is chemically similar to the erupted tuffs, yielded a synchronous weighted mean 206 Pb/ 238 U date of 36.259 ± 0.021 Ma. Weighted mean 206 Pb/ 238 U dates from the larger volume syenitic phase of the underlying Organ Needle pluton range from 36.130 ± 0.031 to 36.071 ± 0.012 Ma, and the youngest sample is 144 ± 20 to 188 ± 20 ka younger than the Squaw Mountain and Achenback Park tuffs, respectively. Younger plutonism in the batholith continued through at least 34.051 ± 0.029 Ma. We propose that the Achenback Park tuff, Squaw Mountain tuff, alkali feldspar granite and Organ Needle pluton formed from a single, long-lived magma chamber/mush zone. Early silicic magmas generated by partial melting of the lower crust rose to form an epizonal magma chamber. Underplating of the resulting mush zone led to partial melting and generation of a highsilica alkali feldspar granite cap, which erupted to form the tuffs. The deeper parts of the chamber underwent continued recharge and crystallization for 144 ± 20 ka after the final eruption. Calculated magmatic fluxes for the Organ Needle pluton range from 0.0006 to 0.0030 km 3 /year, in agreement with estimates from other well-studied plutons. The petrogenetic evolution proposed here may be common to many small-volume silicic volcanic systems.