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324 records · Page 18Linked to original sources
USGS2022

Global tellurium supply potential from electrolytic copper refining

The transition towards renewable energy requires increasing quantities of nonfuel mineral commodities, including tellurium used in certain photovoltaics. While demand for tellurium may increase markedly, the potential to increase tellurium supply is not well-understood. In this analysis, we estimate the quantity of tellurium contained in anode slimes generated by electrolytic copper refining by country between 1986 and 2018, including uncertainties. For 2018, the results indicate that 1930 (1500-2700, 95% confidence interval) metric tons of tellurium were contained in anode slimes globally. This is nearly quadruple the reported tellurium production for that year. China has the greatest potential to increase tellurium supplies. However, most of the tellurium potentially recoverable by Chinese refineries appears to come from copper mined elsewhere. Further research into the business decisions associated with tellurium recovery may help translate the physical availability of tellurium into economic availability. The methodology presented here can be applied to other byproduct elements.

Resources, Conservation & Recycling↗
USGS2017

Rare-earth elements

The rare-earth elements (REEs) are 15 elements that range in atomic number from 57 (lanthanum) to 71 (lutetium); they are commonly referred to as the “lanthanides.” Yttrium (atomic number 39) is also commonly regarded as an REE because it shares chemical and physical similarities and has affinities with the lanthanides. Although REEs are not rare in terms of average crustal abundance, the concentrated deposits of REEs are limited in number. Because of their unusual physical and chemical properties, the REEs have diverse defense, energy, industrial, and military technology applications. The glass industry is the leading consumer of REE raw materials, which are used for glass polishing and as additives that provide color and special optical properties to the glass. Lanthanum-based catalysts are used in petroleum refining, and cerium-based catalysts are used in automotive catalytic converters. The use of REEs in magnets is a rapidly increasing application. Neodymium-iron-boron magnets, which are the strongest known type of magnets, are used when space and weight are restrictions. Nickel-metal hydride batteries use anodes made of a lanthanum-based alloys. China, which has led the world production of REEs for decades, accounted for more than 90 percent of global production and supply, on average, during the past decade. Citing a need to retain its limited REE resources to meet domestic requirements as well as concerns about the environmental effects of mining, China began placing restrictions on the supply of REEs in 2010 through the imposition of quotas, licenses, and taxes. As a result, the global rare-earth industry has increased its stockpiling of REEs; explored for deposits outside of China; and promoted new efforts to conserve, recycle, and substitute for REEs. New mine production began at Mount Weld in Western Australia, and numerous other exploration and development projects noted in this chapter are ongoing throughout the world. The REE-bearing minerals are diverse and often complex in composition. At least 245 individual REE-bearing minerals are recognized; they are mainly carbonates, fluorocarbonates, and hydroxylcarbonates (n = 42); oxides (n = 59); silicates (n = 85); and phosphates (n = 26). Many of the world’s significant REE deposits occur in carbonatites, which are carbonate igneous rocks. The REEs also have a strong genetic association with alkaline magmatism. The systematic geologic and chemical processes that explain these observations are not well understood. Economic or potentially economic REE deposits have been found in (a) carbonatites, (b) peralkaline igneous systems, (c) magmatic magnetite-hematite bodies, (d) iron oxide-copper-gold (IOCG) deposits, (e) xenotime-monazite accumulations in mafic gneiss, (f) ion-absorption clay deposits, and (g) monazite-xenotime-bearing placer deposits. Carbonatites have been the world’s main source for the light REEs since the 1960s. Ion-adsorption clay deposits in southern China are the world’s primary source of the heavy REEs. Monazite-bearing placer deposits were important sources of REEs before the mid-1960s and may be again in the future. In recent years, REEs have been produced from large carbonatite bodies mined at the Mountain Pass deposit in California and, in China, at the Bayan Obo deposit in Nei Mongol Autonomous Region, the Maoniuping deposit in Sichuan Province, the Daluxiang deposit in Sichuan Province, and the Weishan deposit in Anhui Province. Alkaline igneous complexes have recently been targeted for exploration because of their enrichments in the heavy REEs. Information relevant to the environmental aspects of REE mining is limited. Little is known about the aquatic toxicity of REEs. The United States lacks drinking water standards for REEs. The concentrations of REEs in environmental media are influenced by their low abundances in crustal rocks and their limited solubility in most groundwaters and surface waters. The scarcity of sulfide minerals, including pyrite, minimizes or eliminates concerns about acid-mine drainage for carbonatite-hosted deposits and alkaline-intrusion-related REE deposits. For now, insights into environmental responses of REE mine wastes must rely on predictive models.

Professional Paper↗
USGS1978

Lithium, a preliminary survey of its mineral occurrence in flint clay and related rock types in the United States

Maximum concentrations of lithium found in samples of flint clay and associated rocks of Pennsylvanian age in different States, in parts per million (ppm), are: Missouri, 5100; Pennsylvania-Maryland, 2100; Kentucky, 890; Ohio, 660; Alabama, 750; and Illinois, 160. Lithium-bearing kaolin deposits are distributed in the Coastal Plain province from New Jersey to Texas, and one occurs in Idaho; maximum lithium concentrations in samples from these deposits range from 64 to 180 ppm. The maximum concentration found in the Arkansas bauxite region is 460 ppm and that in flint clay in Colorado is 370 ppm. Samples from areas other than Pennsylvania, Maryland, Kentucky and Missouri are relatively few in number, represent mostly commercially valuable clays, and represent only a part of the refractory clay deposits in the United States. Data are not available on the clays associated with these deposits that may be unusable because they contain too much lithium as well as other deleterious elements. In both Pennsylvania and Missouri, lithium contents vary regionally between districts and locally between deposits. In samples containing more than 2000 ppm lithium, the lithium occurs in a dioctahedral chlorite mineral very similar to cookeite, which previously has not been recognized in sedimentary clays. The associated clays consist chiefly of well-crystallized kaolinite. The dioctahedral chlorite, however, seems to be most abundant where diaspore and boehmite occur along with the kaolinite. Barium, chromium, copper, phosphorus and strontium are present in some samples in amounts of several hundred pans per million or more, and may contribute to the failure of some clays to perform satisfactorily in firing tests. Lithium-rich clays could serve as a significant lithium resource in the very distant future. Clays that contain as much as 1% lithium may be common enough in Missouri or in Pennsylvania to be produced as a by-product to help support benefication costs for refractory clays. Sufficient amounts of lithium-rich clay may be found in deposits that have been explored, found unsatisfactory for normal refractory uses, and not developed. The lithium-rich clay in some deposits presently being worked may be worth stockpiling for eventual use.

Energy↗
USGS1977

Entropy, materials, and posterity

Materials and energy are the interdependent feedstocks of economic systems, and thermodynamics is their moderator. It costs energy to transform the dispersed minerals of Earth's crust into ordered materials and structures. And it costs materials to collect and focus the energy to perform work - be it from solar, fossil fuel, nuclear, or other sources. The greater the dispersal of minerals sought, the more energy is required to collect them into ordered states. But available energy can be used once only. And the ordered materials of industrial economies become disordered with time. They may be partially reordered and recycled, but only at further costs in energy. Available energy everywhere degrades to bound states and order to disorder - for though entropy may be juggled it always increases. Yet industry is utterly dependent on low entropy states of matter and energy, while decreasing grades of ore require ever higher inputs of energy to convert them to metals, with ever increasing growth both of entropy and environmental hazard. Except as we may prize a thing for its intrinsic qualities - beauty, leisure, love, or gold - low-entropy is the only thing of real value. It is worth whatever the market will bear, and it becomes more valuable as entropy increases. It would be foolish of suppliers to sell it more cheaply or in larger amounts than their own enjoyment of life requires, whatever form it may take. For this reason, and because of physical constraints on the availability of all low-entropy states, the recent energy crises is only the first of a sequence of crises to be expected in energy and materials as long as current trends continue. The apportioning of low-entropy states in a modern industrial society is achieved more or less according to the theory of competitive markets. But the rational powers of this theory suffer as the world grows increasingly polarized into rich, over-industrialized nations with diminishing resource bases and poor, supplier nations with little industry. The theory also discounts posterity, the more so as population density and percapita rates of consumption continue to grow. A new social, economic, and ecologic norm that leads to population control, conservation, and an apportionment of low-entropy states across the generations is needed to assure to posterity the options that properly belong to it as an important but voiceless constituency of the collectivity we call mankind. ?? 1977 Ferdinand Enke Verlag Stuttgart.

Geologische Rundschau↗
USGS2009

U.S. Geological Survey Science for the Wyoming Landscape Conservation Initiative - 2008 Annual Report

The Wyoming Landscape Conservation Initiative (WLCI) was launched in 2007 in response to concerns about threats to the State's world class wildlife resources, especially the threat posed by rapidly increasing energy development in southwest Wyoming. The overriding purpose of the WLCI is to assess and enhance aquatic and terrestrial habitats at a landscape scale, while facilitating responsible energy and other types of development. The WLCI includes partners from Federal, State, and local agencies, with participation from public and private entities, industry, and landowners. As a principal WLCI partner, the U.S. Geological Survey (USGS) provides multidisciplinary scientific and technical support to inform decisionmaking in the WLCI. To address WLCI management needs, USGS has designed and implemented five integrated work activities: (1) Baseline Synthesis, (2) Targeted Monitoring and Research, (3) Integration and Coordination, (4) Data and Information Management, and (5) Decisionmaking and Evaluation. Ongoing information management of data and products acquired or generated through the integrated work activities will ensure that crucial scientific information is available to partners and stakeholders in a readily accessible and useable format for decisionmaking and evaluation. Significant progress towards WLCI goals has been achieved in many Science and Technical Assistance tasks of the work activities. Available data were identified, acquired, compiled, and integrated into a comprehensive database for use by WLCI partners and to support USGS science activities. A Web-based platform for sharing these data and products has been developed and is already in use. Numerous map products have been completed and made available to WLCI partners, and other products are in progress. Initial conceptual, habitat, and climate change models have been developed or refined. Monitoring designs for terrestrial and aquatic indicators have been completed, pilot data have been collected for terrestrial indicators, and evaluations of alternative monitoring designs are underway. Initial models and map products have been developed for assessing vegetation, surface disturbance, oil and gas resources, mineral resources, surficial geology, invasive species, aspen treatments, ungulate migration corridors, greater sage-grouse (Centrocercus urophasianus), pygmy rabbits (Brachylagus idahoensis), and songbirds, and data were collected or compiled to validate and refine the models. Coordination and collaboration among partners has led to the production of several documents addressing WLCI objectives, strategies, and guiding principles, and has facilitated implementation of on-the-ground habitat treatments.

Open-File Report↗
USGS2017

Niobium and tantalum

Niobium and tantalum are transition metals that are almost always found together in nature because they have very similar physical and chemical properties. Their properties of hardness, conductivity, and resistance to corrosion largely determine their primary uses today. The leading use of niobium (about 75 percent) is in the production of high-strength steel alloys used in pipelines, transportation infrastructure, and structural applications. Electronic capacitors are the leading use of tantalum for high-end applications, including cell phones, computer hard drives, and such implantable medical devices as pacemakers. Niobium and tantalum are considered critical and strategic metals based on the potential risks to their supply (because current production is restricted to only a few countries) and the significant effects that a restriction in supply would have on the defense, energy, high-tech industrial, and medical sectors. The average abundance of niobium and tantalum in bulk continental crust is relatively low—8.0 parts per million (ppm) niobium and 0.7 ppm tantalum. Their chemical characteristics, such as small ionic size and high electronic field strength, significantly reduce the potential for these elements to substitute for more common elements in rock-forming minerals and make niobium and tantalum essentially immobile in most aqueous solutions. Niobium and tantalum do not occur naturally as pure metals but are concentrated in a variety of relatively rare oxide and hydroxide minerals, as well as in a few rare silicate minerals. Niobium is primarily derived from the complex oxide minerals of the pyrochlore group ((Na,Ca,Ce) 2 (Nb,Ti,Ta) 2 (O,OH,F) 7 ), which are found in some alkaline granite-syenite complexes (that is, igneous rocks containing sodium- or potassium-rich minerals and little or no quartz) and carbonatites (that is, igneous rocks that are more than 50 percent composed of primary carbonate minerals, by volume). Tantalum is derived mostly from the mineral tantalite ((Fe,Mn)(Ta,Nb) 2 O 6 ), which is found as an accessory mineral in rare-metal granites and pegmatites that are also enriched in lithium and cesium (termed lithium-cesium-tantalum (LCT)-type pegmatites). Brazil and Canada are the leading nations that produce niobium mineral concentrates, but Brazil is by far the leading producer, accounting for about 90 percent of production, which comes mostly from weathered material derived from carbonatites. Brazil and Canada also have the largest identified niobium resources; additional resources, although they are less well reported, occur in Angola, Australia, China, Greenland, Malawi, Russia, and South Africa. Australia and Brazil have been the leading producers of tantalum mineral concentrates, although recently Ethiopia and Mozambique have also been significant suppliers of tantalum. Artisanal mining of columbite-tantalite (also called coltan) is practiced in many countries, particularly Burundi, the Democratic Republic of the Congo (Congo [Kinshasa]), Nigeria, Rwanda, and Uganda. Brazil has about 40 percent of the identified tantalum resources; other countries and regions with identified tantalum resources include, in decreasing order of resources, Australia, Asia, Russia and the Middle East, Africa, North America, and Europe. Identified niobium and tantalum resources in the United States are small, low grade, and difficult to recover and process, and are thus not commercially recoverable at current prices. Consequently, the United States meets its current and expected future needs for niobium and tantalum through imports of primary mineral concentrates and alloys and through recovery from foreign and domestic alloy scrap that contain the metals. Environmentally, the main issues related to niobium and tantalum mining are land disruptions, the volume of waste materials and their disposal, and the radioactivity of some tailings and waste materials that contain thorium and uranium. Because of the relative biological inertness of niobium and tantalum, human and ecological health concerns are generally minimal under most natural conditions. Demand for both niobium and tantalum is expected to increase as the world economy continues to recover from the downturn that began in 2008. Increased demand for niobium is linked to increased consumption of microalloyed steel, which is used in the manufacture of cars, buildings, ships, and refinery equipment. Demand for these steels will likely increase with continued economic development in such countries as Brazil, China, and India. In addition, increased global demand for cars, cell phones, computers, superconducting magnets, and other high-tech devices will likely spur increased demand for both niobium and tantalum. The estimated global reserves and resources of niobium and tantalum are large and appear more than sufficient to meet global demand for the foreseeable future, possibly the next 500 years. The sale of “conflict coltan” attributed to rebel forces waging a civil war in Congo (Kinshasa) has been of recent concern and has highlighted the need for a transparent and traceable global supply chain that can exclude illegal columbite-tantalite from the conventional market while discerning legitimate artisanal mine production in central Africa.

Professional Paper↗
USGS2016

Recent trends in the nonfuel minerals industry of Iran

Summary In response to the recent removal of international sanctions on Iran, including the lifting of “secondary” sanctions by the United States on investment into and trade with Iran, the U.S. Geological Survey National Minerals Information Center compiled and analyzed available information on the current state of Iran’s nonfuel minerals industry. This Circular features a new map and table that identify existing mines and mineral-processing facilities and provide information on location, ownership, and capacity for metals and industrial minerals whose output levels may substantially change in the near future. Additionally, the report covers Iran’s mineral resources and reserves, official mineral production targets for 2025, and current output and share of global mineral production. Recent trends and developments in individual mineral commodities are discussed, including mineral exploration and partnerships with foreign investors. The U.S. Geological Survey estimated that Iran held globally significant reserves of feldspar (2d largest in the world), barite (5th largest), gypsum (5th largest), fluorspar (8th largest), and iron ore (10th largest). The Government of Iran claimed to also have significant reserves of chromium, copper, gold, manganese, phosphate rock, and zinc. In 2014, Iran was the second-leading producer of gypsum and the sixth-leading producer of barite, with 6.1 percent and 3.6 percent of world output, respectively. Iran was also the world’s 7th-leading producer of cement, feldspar, and fluorspar; 8th-leading producer of bentonite; 9th-leading producer of molybdenum; 11th-leading producer of iron ore; and 14th-leading producer of crude steel. The Government of Iran plans to quadruple the output of aluminum, copper cathode, direct-reduced iron, and iron ore pellets; triple that of crude steel and gold; and double that of cement, pig iron, and zinc by 2025. It also plans to double the contribution of mining and to quadruple that of mineral processing to the national economy in the next decade. In order to achieve these major goals, the construction and expansion of several mines and mineral facilities are planned or under development. Whether Iran’s annual mineral production increases as rapidly as envisioned by the Government will depend largely on the amount of foreign investment into the minerals industry; integration of modern technology into mineral facilities; and availability of energy to aluminum, copper, and steel plants at competitive prices to international investors.

Circular↗
USGS1962

Ground-water investigations of the Project Gnome area, Eddy and Lea Counties, New Mexico

The U.S. Atomic Energy Commission, through the Office of Test Operations, Albuquerque Operations Office, plans to detonate a nuclear device in a massive salt bed 1,200 feet beneath the land surface. The project, known as Project Gnome, is an element of the Plowshare program--a study of peacetime applications of nuclear fission. The location of the proposed underground shot is in a sparsely-populated area in southeastern Eddy County, N. Mex., east of the Pecos River and about 25 miles southeast of the city of Carlsbad. The area is arid to Semiarid and ground water is a vital factor in the economic utilization of the land, which is primarily used for stock raising. An investigation of the Project Gnome site and surrounding area for the purposes of evaluating the ground-water resources and the possible effect upon them from the detonation of the nuclear shot was desired by the Commission. This report describes work done by the U.S. Geological Survey on behalf of the Commission and presents results of the investigation of the ground-water resources and geology of the area. The most intensive investigations were made within a 15-mile radius of the site of Project Gnome and mainly on the east side of the Pecos River. The total area of study of over 1,200 square miles includes parts of Eddy and Lea Counties, N. Mex. The Project Gnome site is in the sedimentary Delaware Basin. It is underlain by about 18,000 feet of sedimentary rocks ranging in age from Ordovician to Recent. Upper Permian evaporitic rocks, which contain the principal source of potash available in the United States, are worked in nearby mines. The potash minerals are found in a massive salt bed about 1,400 feet thick in the Salado Formation of Permian age. The land surface of the area is covered mostly by a wind-blown sand and caliche; however, rocks of the Rustler Formation of Permian age and younger rocks of Permian, Triassic, Pleistocene(?) and Recent age crop out at several localities. Solution by ground water of salt at the top of the Salado Formation and of anhydrite within the Rustler Formation has removed thick sections of these rocks. A subsequent lowering of the land surface and differential collapse of the Rustler has formed many sinkholes and has created a karst topography over much of the western part of the area. Ground water is obtained from rocks of Permian, Triassic, Tertiary, and Quaternary age in the general region. However, the only aquifer at the Gnome site is the Culebra Dolomite Member of the Rustler Formation of Permian age. The aquifer is about 500 feet beneath the surface at the site and is about 30 feet thick. An aquifer, immediately above the top of the salt, contains a brine solution in Nash Draw, a few miles west of the Gnome site. This aquifer discharges into the Pecos River and is a major source of contamination of the river water. No potable water is known to be present in the area below the top of the salt of the Salado Formation. The ground water in the area is generally under artesian pressure. The general direction of ground-water movement is toward the Pecos River both east and west of the river. At the Gnome site the artesian head of the water in the Culebra Dolomite Member is about 7.5 feet. The water moves westward through the aquifer at a rate of about ? foot per day. The most widespread utilization of ground water east of the river is for stock use. Irrigation usage west of the Pecos River accounts for the largest withdrawal of water. Wells range in depth from a few tens of feet to nearly 800 feet. Water levels range from a few feet to about 500 feet below the surface. A test well at the Gnome site drawing water from the Culebra Dolomite Member was pumped at a rate of 100 gpm (gallons per minute); however, most wells east of the river yield only a few gpm. Irrigation wells west of the river yield as much as 3,500 gpm. Most of the water in the area is highly mineralized and is suitable only for use by livest

Open-File Report↗
USGS2019

Nanoscale molecular fractionation of organic matter within unconventional petroleum source beds

Fractionation of petroleum during migration through sedimentary rock matrices has been observed across lengths of meters to kilometers. Selective adsorption of specific chemical moieties at mineral surfaces and/or the phase behavior of petroleum during pressure changes typically are invoked to explain this behavior. Such phenomena are of interest as they impact both the quality and recoverability of petroleum resources. Given the current emphasis on unconventional (continuous) resources, there is a need to understand petroleum fractionation occurring during expulsion and migration at the nanometer to micron scale, due to the fine-grained nature of petroliferous mudrocks. Here, organic matter compositional differences observed within kukersites (petroleum source beds containing acritarch Gloeocapsomorpha prisca) and the overlying carbonate reservoir layer from the Ordovician Stonewall Formation are explored using a suite of spectroscopic methods, primarily through atomic force microscopy based infrared spectroscopy (AFM-IR). AFM-IR is capable of providing spatial resolutions approaching 50 nm and allows for assessment of the molecular fingerprint of kukersite organic matter across transition zones from organic-rich ‘source’ layers into neighboring carbonate ‘reservoir’ layers ~150 μm away. Results indicate that organic matter composition begins to vary immediately following expulsion from source layers, with loss of carbonyl groups and a concomitant decrease in alkyl chain-length, as migration distance increases. These chemical transitions correlate with a decrease in fluorescence intensity, increase in solid bitumen reflectance, and increase in Raman aromaticity proxies (D-G band separation) in the organic matter. Our findings are consistent with the retention of polar compounds onto mineral grains during expulsion and migration, following primary cracking and bituminization of the Gloeocapsomorpha prisca kerogen.

Energy and Fuels↗
USGS2012

Determining the source and genetic fingerprint of natural gases using noble gas geochemistry: a northern Appalachian Basin case study

Silurian and Devonian natural gas reservoirs present within New York state represent an example of unconventional gas accumulations within the northern Appalachian Basin. These unconventional energy resources, previously thought to be noneconomically viable, have come into play following advances in drilling (i.e., horizontal drilling) and extraction (i.e., hydraulic fracturing) capabilities. Therefore, efforts to understand these and other domestic and global natural gas reserves have recently increased. The suspicion of fugitive mass migration issues within current Appalachian production fields has catalyzed the need to develop a greater understanding of the genetic grouping (source) and migrational history of natural gases in this area. We introduce new noble gas data in the context of published hydrocarbon carbon (C 1 ,C 2+ ) ( 13 C) data to explore the genesis of thermogenic gases in the Appalachian Basin. This study includes natural gases from two distinct genetic groups: group 1, Upper Devonian (Marcellus shale and Canadaway Group) gases generated in situ, characterized by early mature ( 13 C[ C1 C2 ][ 13 C 1 13 C 2 ]: –9 ), isotopically light methane, with low ( 4 He) (average, 1 10 3 cc/cc) elevated 4 He/ 40 Ar and 21 Ne / 40 Ar (where the asterisk denotes excess radiogenic or nucleogenic production beyond the atmospheric ratio), and a variable, atmospherically (air-saturated–water) derived noble gas component; and group 2, a migratory natural gas that emanated from Lower Ordovician source rocks (i.e., most likely, Middle Ordovician Trenton or Black River group) that is currently hosted primarily in Lower Silurian sands (i.e., Medina or Clinton group) characterized by isotopically heavy, mature methane ( 13 C [C1 – C2] [ 13 C 1 13 C 2 ]: 3 ), with high ( 4 He) (average, 1.85 10 3 cc/cc) 4 He/ 40 Ar and 21 Ne / 40 Ar near crustal production levels and elevated crustal noble gas content (enriched 4 He, 21 Ne , 40 Ar ). Because the release of each crustal noble gas (i.e., He, Ne, Ar) from mineral grains in the shale matrix is regulated by temperature, natural gases obtain and retain a record of the thermal conditions of the source rock. Therefore, noble gases constitute a valuable technique for distinguishing the genetic source and post-genetic processes of natural gases.

New York↗
USGS2025

A time-space model of graphite mineral systems

Increasing demand for graphite in energy storage systems warrants review of graphite ore genesis in a mineral systems framework. Orogenic graphite encompasses the metamorphic and orogenic mineral systems that produce flake graphite and hydrothermal vein (lump and chip) graphite deposits, respectively. A common feature of orogenic graphite deposits is an association with upper amphibolite- to granulite-facies metasedimentary rocks in continent-continent or continent-island arc collisional orogens. Orogenic flake graphite deposits form primarily through graphitization of organic carbon during regional metamorphism, but strain localization and partial melting of pelitic protoliths are likely important processes for graphite grade and quality enrichment. Orogenic vein graphite deposits precipitate from hydrothermal fluids, possibly derived from metamorphism or anatexis at depth. Decarbonation reactions in mixed calcareous-carbonaceous metasedimentary sequences are the most likely carbon sources for the veins. In contrast, intrusion-related graphite includes magmatic-hydrothermal and metamorphic mineral systems that form primarily in continental arc settings via the interaction of magmas with carbonaceous sedimentary packages. Magmatic-hydrothermal flake graphite deposits are hosted in plutonic and volcanic rocks, and result from the exsolution of CO 2 -CH 4 -rich fluids from melts contaminated by such packages. Contact metamorphism of carbonaceous sedimentary rocks by plutons produces some microcrystalline (amorphous) graphite deposits, including many in China. Compilation of geologic data from known graphite deposits globally suggests that pulses of carbon deposition in the Paleoproterozoic, Mesoproterozoic, and Neoproterozoic provided source carbon material. Subsequent supercontinent orogenesis at ca. 2,100 to 1,700 Ma (Columbia), ca. 1,300 to 1,000 Ma (Rodinia), and ca. 650 to 500 Ma (Gondwana) resulted in the genesis of orogenic flake and vein graphite deposits, where favorable geologic components overlapped with organic ± carbonate carbon-rich strata. Cryogenian deposition of graphite protoliths and Cryogenian – Cambrian metamorphic mineralization account for nearly 75% of all known resources globally and coincide with profound carbon isotope excursions and climate variability, implying a link with the global carbon budget. Comparatively few graphite deposits are associated with Pangea-forming orogens, attributed to less exhumation and/or denudation. High-temperature metasedimentary belts containing organic carbon-rich protoliths are most favorable for hosting orogenic flake graphite deposits, whereas sequences that also contain carbonate protoliths are favorable for orogenic graphite veins. Continent-scale orogenic belts may host both deposit types along with vanadium deposits. Use of a time-space mineral systems framework for graphite deposits can improve exploration models needed to ensure future supply of this critical mineral and provide insights into Earth’s long-term carbon cycle.

Mineralium Deposita↗
USGS1990

Invertebrate communities of small streams in northeastern Wyoming

Invertebrate communities of small streams in an energy-mineral- development area in the Powder River structural basin of northeastern Wyoming were studied during 1980-81. The largest average density of benthic invertebrates among 11 sites was 983 invertebrates/sq ft at a site on a perennial stream, the Little Powder River at State Highway 59. The smallest average densities were 3.4 invertebrates/sq ft in Salt Creek and 16.6 invertebrates/sq ft in the Cheyenne River, two streams where the invertebrates were stressed by degraded water quality or inadequate substrate or both. The rates of invertebrate drift were fastest in three perennial streams, compared to the rates in intermittent and ephemeral streams. Analysis of the invertebrate communities using the Jaccard coefficient of community similarity and a cluster diagram showed communities inhabiting perennial streams were similar to each other, because of the taxa adapted to flowing water in riffles and runs. Communities from sites on ephemeral streams were similar to each other, because of the taxa adapted to standing water and vegetation in pools. Communities of intermittent streams did not form a group; either they were relatively similar to those of perennial or ephemeral streams or they were relatively dissimilar to other communities. The communities of the two streams stressed by degraded water quality or inadequate substrate or both, Salt Creek and the Cheyenne River, were relatively dissimilar to communities of the other streams in the study. (USGS)

Water-Resources Investigations Report↗
USGS2010

Temperature data from wells in Long Valley Caldera, California

The 30-by-20-km Long Valley Caldera (LVC) in eastern California (fig.1) formed at 0.76 Ma in a cataclysmic eruption that resulted in the deposition of 600 km? of Bishop Tuff outside the caldera rim (Bailey, 1989). By approximately 0.6 Ma, uplift of the central part of the caldera floor and eruption of rhyolitic lava formed the resurgent dome. The most recent eruptive activity in the area occurred approximately 600 yr ago along the Mono-Inyo craters volcanic chain (Bailey, 2004; Hildreth, 2004). LVC hosts an active hydrothermal system that includes hot springs, fumaroles, mineral deposits, and an active geothermal well field and power plant at Casa Diablo along the southwestern boundary of the resurgent dome (Sorey and Lewis, 1976; Sorey and others, 1978; Sorey and others, 1991). Electric power generation began in 1985 with about 10 Mwe net capacity and was expanded to about 40 Mwe (net) in 1991 (Campbell, 2000; Suemnicht and others, 2007). Plans for further expansion are focused mainly on targets in the caldera?s western moat (Sass and Priest, 2002) where the most recent volcanic activity has occurred (Hildreth, 2004). LVC has been the site of extensive research on geothermal resources and volcanic hazards (Bailey and others, 1976; Muffler and Williams, 1976; Miller and others, 1982; Hill and others 2002). The first geothermal exploratory drilling was done in the shallow (< 200 m deep) hydrothermal system at Casa Diablo in the 1960?s (McNitt, 1963). Many more boreholes were drilled throughout the caldera in the 1970?s and 1980?s by private industry for geothermal exploration and by the U.S. Geological Survey (USGS) and Sandia National Laboratory for volcanic and geothermal research and exploration. Temperature logs were obtained in some of these wells during or immediately following drilling, before thermal equilibration was complete. Most of the temperature logs, however, were obtained weeks, months, or years after well completion and are representative of dynamic thermal equilibrium. The maximum reservoir temperature for LVC is estimated to be about 220?C on the basis of chemical geothermometers (Fournier and Truesdell, 1973) using analytical results from water samples collected from a large number of wells and springs across the caldera and around its periphery (Lewis, 1974; Mariner and Wiley, 1976; Farrar and others, 1985, 1987, 1989, White and Peterson, 1991). The deepest well in LVC (~3 km) is the Long Valley Exploratory Well (LVEW) drilled in the 1990?s with funding from the U.S. Department of Energy to investigate the potential for near-magmatic-temperature energy extraction and the occurrence of magma under the central part of the resurgent dome (Finger and Eichelberger, 1990; Finger and Jacobsen, 1999; Sackett and others, 1999). However, temperatures beneath the resurgent dome have proved disappointingly low and in LVEW reach a maximum of only 102 degrees C in a long isothermal section (2,100 to 3,000 m) in Mesozoic basement rocks (Farrar and others, 2003). Temperature data from well logs and geothermometry reveal that the highest temperatures in LVC are beneath the western moat. The hottest temperatures measured in LVC exceed 200 degrees C in two wells (44-16 and RDO-8) located in the western moat. Well 44-16 was drilled through the entire thickness of post-caldera volcanic fill and bottomed in Mesozoic basement. Well RDO-8 was drilled through post-caldera volcanic rocks and 305 m into the Bishop Tuff (Wollenberg and others, 1986). Temperatures in the hydrothermal system decrease toward the east by processes of conduction and dilution from cold groundwater recharge that occurs mostly around the caldera margin and beneath the resurgent dome. Reservoir temperatures at Casa Diablo (fig.1) are about 170?C (for example, MBP-3 and Mammoth-1), decreasing to about 100 degrees C in wells near Hot Creek Gorge (for example, MW-4 and CH-10B), and are generally less than 50?C in thermal springs near Lake

Data Series↗
USGS2007

Determining the pattern of cementum annuli and relationship to reproduction in male sea otters

Since the early 1990s, the southwestern Alaskan sea otter (Enhydra lutris) population has declined dramatically and the cause has yet to be determined. Population trajectories of large mammals are determined by three factors: survival rate, reproduction rate, and age of first reproduction (AFR). Of these three, AFR should respond first to environmental change. Life history theory predicts that AFR will be older with bottom-up causes (ie, food limitation) and younger when the cause of the decline is top-down (ie, predation), as there is usually abundant resources in this scenario. Traditionally, determining AFR required lethal sampling, which may not always be possible. Work on many mammalian species suggests that the width of annual cementum layers in teeth may decline when breeding begins. If so, examining teeth annuli may provide a nonlethal alternative for determining AFR. Ongoing research has shown this relationship in female sea otters, but male sea otters have not been tested. Sea otter testes and premolar teeth slides were collected by subsistence hunters working with the US Fish and Wildlife Service and the Alaska Sea Otter and Steller Sea Lion Commission from Alaska (1994– 2005). We determined the pattern in cementum annuli thickness for male sea otters across age by measuring annuli at three sites on each of the two slide sections available. We found that cementum annuli layers decreased with age, but found no correlation between cementum annuli and sexual maturity in male sea otters. This lack of correlation may be due to sampling error or different energy expenditures during reproduction for each sex. Since females expend large amounts of energy through gestation and lactation, we hypothesize that the width of female cementum annuli decreases at a much sharper rate when they reach AFR. The southwest Alaskan sea otter population has plummeted up to 90% since the early 1990s and the reason is unknown.1 Declines may be due to a bottom-up source caused by lack of food and habitat that occurs when populations are dense, in which case we would expect reproduction rates to decrease and age of first reproduction (AFR) to increase. However, circumstantial evidence suggests that the decline may be due to a top-down source, ie, predation.2 In this case, we would expect reproduction rates to increase and AFR to decrease due to lowered densities that coincide with top-down declines.3 An ongoing study of female sea otters has shown that past reproduction can be determined by analysis of cementum annuli in the teeth, and used to calculate AFR.4 Cementum annuli are annual deposits of minerals that occur on the root of a tooth that correspond to the growth of the animal (Figure 1). During summer and spring, growth is fast which accounts for the white area, but during winter, growth slows down and the cementum is compressed which accounts for a darkened line. In females, the relationship between cementum width declines and reproduction likely reflects the large expenditure of energy that is required during gestation and lactation. However, male and female mammals expend energy for reproduction in very distinct ways,3 and the same pattern of cementum decline may not be present in males. Since shifts in the life history strategy of males are poorly understood, we are interested in testing the relationship between cementum declines and reproduction in male sea otters using cementum analysis.

Ethnicity and Disease↗
USGS2005

Crystalline-rock ejecta and shocked minerals of the Chesapeake Bay impact structure, USGS-NASA Langley core, Hampton, Virginia, with supplemental constraints on the age of impact

The USGS-NASA Langley corehole at Hampton , Va., was drilled 2000 as the first in a series of new coreholes drilled in the late Eocene Chesapeake Bay impact structure to gain a comprehensive understanding of its three-dimensional character. This understanding is important for assessing ground-water resources in the region, as well as for learning about marine impacts on Earth. We studied crystalline-rock ejecta and shock-metamorphosed minerals from the Langley core to determine what they reveal about the geology of crystalline rocks beneath the Atlantic Coastal Plain and how those rocks were affected by the impact . An unusual polymict diamicton, informally called the Exmore beds (upper Eocene), is 33.8 meters (m; 110.9 feet (ft)) thick and lies at a depth of 269.4 to 235.65 m (884.0 to 773.12 ft) in the core . This matrix-supported sedimentary deposit contains clasts of Tertiary and Cretaceous sediment (ranging up to boulder size) and sparse pebbles of crystalline rock . The matrix consists of muddy sand that contains abundant quartz grains and minor glauconite and potassium feldspar. Significantly, the sandy matrix of the Exmore beds contains sparse quartz grains (0.1 to 0.3 millimeter (0.004 to 0.012 inch) in diameter) that contain multiple sets of intersecting planar deformation features formerly referred to as shock lamellae. As many as five different sets have been observed in some quartz grains. Planar deformation features also occur in quartz grains in reworked crystalline-rock clasts in the Exmore beds. Such grains are clearly of shock-metamorphic origin. The presence of these features indicates that the quartz grains have experienced pressures greater than 6 gigapascals (GPa) and strain rates greater than 10 6 /second. Thus, the shock-metamorphosed quartz grains, although rare, provide clear and convincing evidence that the Exmore beds are of hybrid impact origin. Identification of shocked quartz grains in the Langley core adds to the number of sites in the structure where their presence is confirmed. Most of the clasts of crystalline rock that are in and just below the Exmore beds are rounded, detrital, and typical of coastal plain sediments. However, a few have angular shapes and consist of cataclastically deformed felsite having aphanitic-porphyritic to aphanitic texture and peraluminous rhyolite composition. Three of these clasts contain quartz grains that display two sets of planar deformation features of shock-metamorphic origin. Shock-metamorphosed quartz is an integral part of the cataclastic fabric in these three clasts, indicating that both the fabric and the shocked quartz were produced by the same high-energy impact event. Some felsite clasts have spherulitic textures that may be features either of an impact melt or of preimpact volcanic rocks. A weighted-mean total-fusion 40 Ar/ 39 Ar age of 35.3±0.1 Ma (±lσ) for 19 analyses of 4 North American tektites records the age of the late Eocene Chesapeake Bay impact event.

Chesapeake Bay↗
USGS2014

Geophysical investigations of the geologic and hydrothermal framework of the Pilgrim Springs Geothermal Area, Alaska

Pilgrim Hot Springs, located on the Seward Peninsula in west-central Alaska, is characterized by hot springs, surrounding thawed regions, and elevated lake temperatures. The area is of interest because of its potential for providing renewable energy for Nome and nearby rural communities. We performed ground and airborne geophysical investigations of the Pilgrim Springs geothermal area to identify areas indicative of high heat flow and saline geothermal fluids, and to map key structures controlling hydrothermal fluid flow. Studies included ground gravity and magnetic measurements, as well as an airborne magnetic and frequency-domain electromagnetic (EM) survey. The structural and conceptual framework developed from this study provides critical information for future development of this resource and is relevant more generally to our understanding of geothermal systems in active extensional basins. Potential field data reveal the Pilgrim area displays a complex geophysical fabric reflecting a network of intersecting fault and fracture sets ranging from inherited basement structures to Tertiary faults. Resistivity models derived from the airborne EM data reveal resistivity anomalies in the upper 100 m of the subsurface that suggest elevated temperatures and the presence of saline fluids. A northwest trending fabric across the northeastern portion of the survey area parallels structures to the east that may be related to accommodation between the two major mountain ranges south (Kigluaik) and east (Bendeleben) of Pilgrim Springs. The area from the springs southward to the range front, however, is characterized by east-west trending, range-front-parallel anomalies likely caused by late Cenozoic structures associated with north-south extension that formed the basin. The area around the springs (~10 km2 ) is coincident with a circular magnetic high punctuated by several east-west trending magnetic lows, the most prominent occurring directly over the springs. These features possibly result from hydrothermal alteration imposed by fluids migrating along intra-basin faults related to recent north-south extension. The Pilgrim River valley is characterized by a NE-elongate gravity low that reveals a basin extending to depths of ~300 m beneath Pilgrim Springs and deepening to ~800 m to the southwest. The margins of the gravity low are sharply defined by northeasttrending gradients that probably reflect the edges of fault-bounded structural blocks. The southeastern edge of the low, which lies very close to the springs, also corresponds with prominent NE-striking anomalies seen in magnetic and resistivity models. Together, these features define a structure we refer to as the Northeast Fault. The location of the hot springs appears to be related to the intersection of the Northeast Fault with a N-oriented structure marked by the abrupt western edge of a resistivity low surrounding the hot springs. While the hot springs represent the primary outflow of geothermal fluids, additional outflow extends from the springs northeast along the Northeast fault to another thaw zone that we interpret to be a secondary region of concentrated upflow of geothermal fluids. The Northeast Fault apparently controls shallow geothermal fluid flow, and may also provide an important pathway conveying deep fluids to the shallow subsurface. We suggest that geothermal fluids may derive from a reservoir residing beneath the sediment basin southwest of the springs. If so, the shape of the basin, which narrows and shallows towards the springs, may funnel fluids beneath the springs where they intersect the Northeast Fault allowing them to reach the surface. An alternative pathway for reservoir fluids to reach intermediate to shallow depths may be afforded by the main Kigluaik range front fault that coincides with a resistivity anomaly possibly resulting from fluid flow and associated hydrothermal mineralization occurring within the fault zone.

Conference Paper↗
USGS1984

A workshop model simulating fate and effect of drilling muds and cuttings on benthic communities

Oil and gas exploration and production at marine sites has generated concern over potential environmental impacts resulting from the discharge of spent drilling muds and cuttings. This concern has led to a broad array of publicly and privately sponsored research. This report described a cooperative modeling effort designed to focus information resulting from this research through construction of explicit equations that simulate the potential impacts of discharge drilling fluids (muds) and cuttings on marine communities. The model is the result of collaboration among more than 30 scientists. The principal cooperating organizations were the E.S. Environmental Protection Agency, the U.S. Minerals Management Service, the Offshore Operators Committee, and the Alaska Oil and Gas Association. The overall simulation model can be conceptualized as three connected submodels: Discharge and Plume Fate, Sediment Redistribution, and Benthic Community Effects. On each day of simulation, these submodels are executed in sequence, with flows of information between submodels. The Benthic Community Effects submodel can be further divided into sections that calculate mortality due to burial, mortality due to toxicity, mortality due to resuspension disturbance, and growth of the community. The model represents a series of seven discrete 1-m 2 plots at specified distances along a transect in one direction away from a discharge point. It consists of coupled difference equations for which parameter values can easily be set to evaluate different conditions or to examine the sensitivity of output to various assumptions. Sets of parameter values were developed to represent four general cases or scenarios: (1) a shallow (5 m), cold environment with ice cover during a substantial fraction of the year, such as might be encountered in the Beaufort Sea, Alaska; (2) a shallow (20 m), temperate environment, such as might be encountered in the Gulf of Mexico; (3) a deeper (80 m), temperate environment, such as might be encountered in the Gulf of Mexico; and (4) a very deep (1,000 m) environment, such as might be encountered on the Atlantic slope. The focus of the modeling effort was on the connection of a reasonable representation of physical fate to the biological responses of populations, rather than on highly detailed representations of individual processes. For example, the calculations of physical fate are not as detailed as those in the recently published model of Brandsma et al. (1983). The value of the model described herein is in the broad scope of processes that are explicitly represented and linked together. The model cannot be considered to produce reliable predictions of the quantitative impacts of discharged drilling fluids and cuttings on biological populations at a particular site. Limitations of the model in predicting integrated fate and effects can be traced to three general areas: level of refinement of the algorithms used in the model; lack of understanding of the processes determining fate and effects; and parameter and data values. Despite the limitations, several qualitative conclusions concerning both potential impacts and the importance of various remaining data gaps can be drawn from the modeling effort. These include: (1) Simple, unequivocal conclusions about fate and effects across geographical regions and drilling operations are difficult, if not misleading, due to the large amount of variability in characteristics of discharged materials (e.g., oil content and toxicity), discharge conditions (e.g., duration of drilling operations), physical environments (e.g., water depth, current direction, and sediment disturbance regimes), and biological communities (e.g., intrinsic growth rates). Different combinations of these characteristics can result in substantial differences in simulated environmental fate and biological effects. For examples, simulated recovery in some high-energy environments occurs within months after the cessation of discharge operations, even at heavily impacted sites, whereas simulated recover in some low-energy environments takes years at heavily impacted sites. <2) Considerable difficulties remain in the reliable extrapolation of results from laboratory toxicity experiments to predictions of population effects in the field. (3) The volume of material discharged and duration of operations in the production drilling operations simulated by the model are sufficient to produce substantial simulated biological impacts at some plots, both in terms of differences from a control plot during the period of discharge operations, and in terms of the recovery period following the perturbations. Evaluation of the significance of potential effects involves the following factors: • Definition of a specific spatial and temporal reference frame (e.g., What is the natural variation? Is 1 year to be considered a "long" or "short" time? Is 50 m to be considered a "large" or "trivial" distance? • Consideration of rare or unique resources and particularly sensitive biotic assemblages. • Consideration of the potential for long term, cumulative effects. Some of these aspects are clearly beyond the scope of this modeling efforts (e.g., the model does not simulate the long term fate of resuspended material). The model does, however, contain an internal "reference frame" by comparison to simulated behavior at a control plot. The model, in general, simulates substantial "natural" variation at the reference or control plots, both over time, due to sediment disturbance events in medium to high energy environments, and over space, due to geographically varying conditions, such as water depth and current regime.

Report↗
USGS2003

Geochemistry of the Birch Creek Drainage Basin, Idaho

The U.S. Survey and Idaho State University, in cooperation with the U.S. Department of Energy, are conducting studies to describe the chemical character of ground water that moves as underflow from drainage basins into the eastern Snake River Plain aquifer (ESRPA) system at and near the Idaho National Engineering and Environmental Laboratory (INEEL) and the effects of these recharge waters on the geochemistry of the ESRPA system. Each of these recharge waters has a hydrochemical character related to geochemical processes, especially water-rock interactions, that occur during migration to the ESRPA. Results of these studies will benefit ongoing and planned geochemical modeling of the ESRPA at the INEEL by providing model input on the hydrochemical character of water from each drainage basin. During 2000, water samples were collected from five wells and one surface-water site in the Birch Creek drainage basin and analyzed for selected inorganic constituents, nutrients, dissolved organic carbon, tritium, measurements of gross alpha and beta radioactivity, and stable isotopes. Four duplicate samples also were collected for quality assurance. Results, which include analyses of samples previously collected from four other sites, in the basin, show that most water from the Birch Creek drainage basin has a calcium-magnesium bicarbonate character. The Birch Creek Valley can be divided roughly into three hydrologic areas. In the northern part, ground water is forced to the surface by a basalt barrier and the sampling sites were either surface water or shallow wells. Water chemistry in this area was characterized by simple evaporation models, simple calcite-carbon dioxide models, or complex models involving carbonate and silicate minerals. The central part of the valley is filled by sedimentary material and the sampling sites were wells that are deeper than those in the northern part. Water chemistry in this area was characterized by simple calcite-dolomite-carbon dioxide models. In the southern part, ground water enters the ESRPA. In this area, the sampling sites were wells with depths and water levels much deeper than those in the northern and central parts of the valley. The calcium and carbon water chemistry in this area was characterized by a simple calcite-carbon dioxide model, but complex calcite-silicate models more accurately accounted for mass transfer in these areas. Throughout the geochemical system, calcite precipitated if it was an active phase in the models. Carbon dioxide either precipitated (outgassed) or dissolved depending on the partial pressure of carbon dioxide in water from the modeled sites. Dolomite was an active phase only in models from the central part of the system. Generally the entire geochemical system could be modeled with either evaporative models, carbonate models, or carbonate-silicate models. In both of the latter types of models, a significant amount of calcite precipitated relative to the mass transfer to and from the other active phases. The amount of calcite precipitated in the more complex models was consistent with the amount of calcite precipitated in the simpler models. This consistency suggests that, although the simpler models can predict calcium and carbon concentrations in Birch Creek Valley ground and surface water, silicate-mineral-based models are required to account for the other constituents. The amount of mass transfer to and from the silicate mineral phases was generally small compared with that in the carbonate phases. It appears that the water chemistry of well USGS 126B represents the chemistry of water recharging the ESRPA by means of underflow from the Birch Creek Valley.

Idaho↗