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At least 271 records · Page 15Linked to original sources

Resource nationalism in Indonesia—Effects of the 2014 mineral export ban

Resource nationalism encompasses a broad range of political and economic actions taken by Governments to regulate the extraction of natural resources within their borders. Policies such as increased tariffs or export restrictions can have far-reaching economic effects on international trade. As the Governments of several developing countries consider enacting nationalistic policies, an examination of the 2014 mineral export ban in Indonesia provides an instructive example of the possible impacts of resource nationalism. Significant changes in the production and trade of unprocessed (that is, ores and concentrates) and processed (that is, refined metal) aluminum, copper, and nickel before and after the export ban form the basis of this study. The U.S. Geological Survey (USGS) National Minerals Information Center (NMIC) tracks production and trade of mineral commodities between producer and consumer countries. Materials flow studies clarify the effects of an export ban on different mineral commodities by assessing changes in production, processing capacity, and trade. Using extensive data collection and monitoring procedures, the USGS NMIC investigated the effects of resource nationalism on the flow of mineral commodities from Indonesia to the global economy.

Fact Sheet↗

Lineament analysis of mineral areas of interest in Afghanistan

During a preliminary mineral resource assessment of Afghanistan (Peters and others, 2007), 24 mineralized areas of interest (AOIs) were highlighted as the focus for future economic development throughout various parts of the country. In addition to located mineral resources of value, development of a viable mining industry in Afghanistan will require the location of suitable groundwater resources for drinking, processing of mineral ores for use or for export, and for agriculture and food production in areas surrounding and supporting future mining enterprises. This report and accompanying GIS datasets describe the results of both automated and manual mapping of lineaments throughout the 24 mineral occurrence AOIs described in detail by Peters and others (2007; 2011). For this study, we define lineaments as "mappable linear or curvilinear features of a surface whose parts align in a straight or slightly curving relationship that may be the expression of a fault or other linear zones of weakness" as derived from remote sensing sources such as optical imagery, radar imagery or digital elevation models (DEMs) (Sabins, 2007). Water wells in bedrock aquifers are generally more productive where boreholes intersect fractures or fracture zones. Lineament identification and analysis have long been used as a reconnaissance tool to identify such favorable conditions for groundwater resources in carbonate bedrock environments (Lattman and Parizek, 1964; Siddiqui and Parizek, 1971). More recently, lineament analysis has been used to identify areas of greater well yields in other bedrock settings, such as crystalline bedrock (Mabee and other, 1994; Moore and others, 2002). Lineaments provide an indication of bedrock areas that warrant further investigation for optimal water well placement. They may also indicate areas of preferential flow and storage of groundwater, and, thus, areas with a greater density of lineaments may indicate greater secondary porosity. Lineaments may indicate structurally trending mineralized areas (for example, Mars and Rowan, 2007), or locations of near-surface water resources, especially when surface vegetation growth coincides with lineaments. The purpose of this report and accompanying GIS data is to provide lineament maps that give one indication of areas that warrant further investigation for optimal bedrock water-well placement within 24 target areas for mineral resources (Peters and others, 2011). These data may also support the identification of faults related to modern seismic hazards (for example, Wheeler and others, 2005; Ruleman and others, 2007), as well as support studies attempting to understand the relationship between tectonic and structural controls on hydrothermal fluid flow, subsequent mineralization, and water-quality issues near mined and unmined mineral deposits (for example, Eppinger and others, 2007).

Open-File Report↗

Reconnaissance for uranium in New Mexico in 1953

In the fall of 1953 a reconnaissance search for uranium was made in the Datil area, west-central New Mexico, and in the Cerrillos, Glorieta, and Tecolote districts and the Las Vegas and Colfax Sill areas in north-central and northeastern New Mexico. Traces of radioactive materials were detected at many places and occurrences of uranium minerals that may be of possible economic significance were found in the Datil area, near the village of Datil. Small amounts of uranium are widespread in sandstone beds in the Mesaverde formation. The highest-grade sample contained 0.056 percent uranium.

New Mexico↗

Heavy-Mineral Placer Potential Map of the U.S. Continental Shelf, Western and Northern Gulf of Mexico

The establishment of the Exclusive Economic Zone (EEZ) in 1983 by Presidential Proclamation opened for natural resource exploration a vast offshore frontier area contiguous to the United States and its territories. The EEZ extends from the seaward limit of state waters (3 nautical mi from shore) to 200 nautical mi offshore, and it includes the continental shelves. Within the context of the EEZ natural resource assessment effort, the purpose of this study is to delineate, on a regional basis, the potential for heavy-mineral placers on the U.S. Continental Shelf in the western and northern Gulf of Mexico from the United States-Mexico border to the Alabama-Florida state line. This map is intended to serve as a general guide for placer exploration. It shows favorable sea-floor areas for placer occurrence in water depths ranging from 0 to 100 fathoms (600 ft). The map can be used as a guide for focusing costly exploratory efforts, such as coring operations and geophysical surveys. The potential economic value of heavy-mineral placer concentrations on the U.S. Continental Shelf is a function of both geologic and economic variables. Geologic variables include the composition and concentration of the heavy-mineral assemblages and their environment of deposition. Economic variables include the current world market price of extracted metals, as well as the cost of mining, processing, and marketing the metals. These economic factors, in turn, are tempered by the nation1s socio-political climate, which determines its need for specific mineral resources at any given time.

Miscellaneous Field Studies Map↗

Geology and Nonfuel Mineral Deposits of Africa and the Middle East

A nation's endowment of nonfuel mineral resources, relative to the world's endowment, is a fundamental consideration in decisions related to a nation's economic and environmental well being and security. Knowledge of the worldwide abundance, distribution, and general geologic setting of mineral commodities provides a framework within which a nation can make decisions about economic development of its own resources, and the economic and environmental consequences of those decisions, in a global perspective. The information in this report is part of a U.S. Geological Survey (USGS) endeavor to evaluate the global endowment of both identified and undiscovered nonfuel mineral resources. The results will delineate areas of the world that are geologically permissive for the occurrence of undiscovered selected nonfuel mineral resources together with estimates of the quantity and quality of the resources. The results will be published as a series of regional reports; this one provides basic data on the identified resources and geologic setting, together with a brief appraisal of the potential for undiscovered mineral resources in Africa and the Middle East. Additional information, such as production statistics, economic factors that affect the mineral industries of the region, and historical information, is available in U.S. Geological Survey publications such as the Minerals Yearbook and the annual Mineral Commodity Summaries (available at http://minerals.usgs.gov/minerals).

Open-File Report↗

Genesis of the Silsilah tin deposit, Kingdom of Saudi Arabia

The Silsilah tin deposit (lat 25 degrees 06' N, long 42 degrees 40' E) consists of a group of pervasively greisenized, flat-topped granite cupolas within a 12-km-diam ring complex. The greisens contain varying amounts of disseminated cassiterite and wolframite. Several types of quartz veins are peripheral to the greisens; some of these contain minor wolframite. The deposit is genetically associated with a highly differentiated, peraluminous alkali-feldspar granite (587 + or - 8 Ma) that is part of a mostly peralkaline, igneous ring complex intruded into Late Proterozoic, immature sandstones of the Murdama Group. We recognize four distinct phases of the peraluminous granite. Only the smallest, most highly differentiated cupolas contain significant tin greisen mineralization. Greisens developed beneath aplitic carapaces that overlie the granite and created impermeable barriers to rising volatiles. The geometry of a cupola correlates strongly with the intensity of alteration; cupolas with the smallest cross sectional areas and steepest marginal contacts have the most intensely greisenized apexes. The paragenetic sequence can be divided into five stages: pegmatite formation, locally pervasive albitization, locally pervasive greisenization and deposition of cassiterite, deposition of quartz-wolframite veins, and deposition of quartz veins with minor base metal sulfides. Pressure-corrected fluid inclusion filling temperatures indicate that the hydrothermal system generally cooled as it evolved and that the delta 18 O values of the hydrothermal quartz increased from 10.8 to 15.7 per mil. Calculated delta 18 O values of the hydrothermal fluid varied concomitantly from the pegmatite stage (delta 18 O fluid approximately 8.6ppm; T [asymp] 550 degrees C) to the greisen stage (5.4 and 5.6[ppm; T [asymp] 360 degrees C), the quartz-wolframite vein stage (6.3 and 7.5ppm; T [asymp] 390 degrees C), and the late vein stage (4.0 and 5.1ppm; T [asymp] 270 degrees C). This evolution probably reflects the admixture of generally increasing amounts of meteoric or formation water having a lower delta 18 O value into the cooling magmatic hydrothermal system. In delta 18 O -delta 18 O plots for mineral separates from fresh to altered samples of the peraluminous granite the values for quartz and feldspar conform to a steep, positive-sloped disequilibrium trend that indicates interaction with high 18 O hydrothermal fluid, mirrored by a negative-sloped disequilibrium trend for quartz and mica. These complementary trends suggest strongly that individual granite cupolas were essentially closed systems during alteration. To our knowledge, this is the first oxygen isotope demonstration of a closed-system, hydrothermal metal deposit. The sandstone country rock has whole-rock delta 18 O values of 12.4 + or - 2.0 per mil. The highest values (>13ppm) form a approximately 3-km-wide high delta 18 O annulus immediately peripheral to the ring complex. The data suggest that the country rocks were pervasively exchanged with an outward-migrating, high delta 18 O fluid moving down a temperature gradient. This fluid was probably formation water that flowed radially inward toward the pluton at a deeper level, forming a largely horizontal, unicellular flow system that had fluid-flow lines nearly vertical next to the intrusion, and directed upward and outward at higher levels. Low delta 18 O fluids that formed quartz associated with the tin-tungsten mineralization and later veins are inferred to be the result of a subsequent and distinct phase of the hydrothermal system. Almost all the geologic processes necessary for the formation of an economically viable tin deposit occurred at Silsilah, but the lack of a strong localizing mechanism for cassiterite mineralization resulted in an economically marginal deposit. If the greisenized cupolas had been vertically stacked, as are the intrusions and ore zones in Climax-type molybdenum deposits, or if the mineralizing fluids had been channeled into veins, as in the tin deposits in Cornwall, England, a higher grade deposit might have formed. The generally closed-system behavior of the hydrothermal system at Silsilah may have prevented additional scavenging of metals and the formation of a larger, richer deposit.

Economic Geology↗

Industrial minerals of the Midcontinent: Proceedings of the Midcontinent industrial minerals workshop

The Midcontinent Industrial Minerals Workshop, in St. Louis, Missouri, September 16-17, 1991, was the fourth U.S. Geological Survey-sponsored meeting on the essential role of industrial rocks and minerals in the Nation's social and economic framework. The meeting was organized, supported, and the agenda was determined by a group from the USGS, the U.S. Bureau of Mines, and the State geological surveys of Arkansas, Illinois, Kansas, Kentucky, Missouri, Nebraska, and Oklahoma, with early assistance in planning from the Iowa and Tennessee surveys. As the major industrial rocks and minerals used in the nine-State area of the Midcontinent are construction materials, the Workshop focused on sand and gravel and limestone-dolomite resources and the extraction industry for those materials. Because active audience participation was considered vital, representatives from industry, universities, geological surveys, planning groups, regulatory agencies, and State legislatures were invited. The audience consisted of 87 attendees out of 120 invited participants (no legislators attended).

Bulletin↗

Maps Showing Distribution of Heavy Minerals on the South Texas Outer Continental Shelf

Heavy minerals constitute a natural resource which, under proper conditions, could have potential economic significance. The purpose of this report is to describe the heavy-mineral distribution in sea-floor sediments On the South Texas Outer Continental Shelf (OCS) within the northwestern Gulf of Mexico. The South Texas OCS encompasses approximately 24,500 sq km extending southward from Matagorda Bay to the U.S.-Mexico border (fig. 1). In a shoreward direction, the OCS extends from the 180-m isobath to the Federal-State water boundary (16.6 km offshore); however, the mineral distribution patterns presented in these maps have been extrapolated slightly shoreward of the l5-m isobath. This work was part of a regional environmental studies program in the South Texas OCS that was conducted in conjunction with the offshore petroleum-lease sales, under the auspices of the U.S. Bureau of Land Management. Some previous work on heavy minerals within the OCS had been done by van Andel and Poole (1960) and van Andel (1960); the fOrIner work was based on relatively few OCS samples and was part of a broader regional study of the northern Gulf of Mexico.

Miscellaneous Field Studies Map↗

Effects of Chinese mineral strategies on the U.S. minerals industry

For more than two decades now, China has been undergoing rapid economic growth and industrialization. The industrialization and urbanization of the once rural, farming nation is leading to increased consumption of mineral commodities to build infrastructure and to make into consumer goods. This increased consumption has led to higher mineral prices, lower stocks and, in some cases, temporary shortages of minerals. Chinese mineral producers and manufacturers are responding by building capacity, restructuring and modernizing industrial sectors and establishing international network that compete with those of the United States and other nations.

Mining Engineering↗

Occurrences of alunite, pyrophyllite, and clays in the Cerro La Tiza area, Puerto Rico

A deposit of hydrothermally altered rocks in the Cerro La Tiza area located between the towns of Comerio and Aguas Buenas, approximately 25 kilometers southwest of San Juan, Puerto Rico, was mapped and studied to determine the principal minerals, their extent distribution and origin, and the possibility of their economic utilization, especially in Puerto Rico. The Cerro la Tiza area is about 7 1 / 2 kilometers long, has an average width of about 1 1 / 2 kilometers and embraces a total area of approximately 15 square kilometers. The principal mineralized zone, a dike-like mass of light-colored rocks surrounded by dark-colored volcanic country rocks, occupies the crest and upper slopes of east-trending Cerro La Tiza ridge and is believed to be of Late Cretaceous or Eocene age. This zone is approximately 5,300 meters long, 430 meters wide and has an area of approximately 225 hectares (556 acres). The rocks of the mineralized zone are of mixed character and consist mainly of massive quartzose rocks and banded quartz-alunite rocks closely associated with foliated pyrophyllitic, sericitic and clayey rocks. The principal minerals in probably order of abundance are quartz, alunite, pyrophyllite, kaolin group clays (kaolinite and halloysite) and sericite. Minerals of minor abundance are native sulfure, diaspore, svanbergite (?), sunyite (?), hematite, goethite, pyrite, rutile (?) and very small quantities of unidentified minerals. The mineralized zone has broken down to deposits of earth-rock debris of Quaternary age that cover much of the slopes and flanks of Cerro La Tiza. This debris consists generally of fragments and boulders with a very large size range embedded in a clayey matrix. The distribution of the earth-rock debris with respect to the present topography and drainage suggests that it may have undergone at least two cycles of erosion. Underlying the earth-rock debris and completely enclosing the mineralized zone are country rocks of probably Late Cretaceous age. These consist principally of low flows and volcanic and flow breccias but contain thin interbedded siltstones and sandstones. The lavas are generally predominant at the western end of the area and the breccias at the eastern end. The mineralized zone and the country rocks are sheared along two predominant directions that are approximately N 70 degrees E and N 70 degrees W. The ridge of Cerro La Tiza appears to be a broad shear zone through which hydrothermal emanations gained access to the country rocks. The emanations are believed to have originated from intrusive rocks that probably underlie the area. The surrounding area contains both large and small exposed intrusive bodies. The largest one is the San Lorenzo batholith of Late Cretaceous or Eocene age whose exposed northwest edge is approximately 19 kilometers southeast of the eastern end of the Cerro La Tiza area. Other zones of hydrothermally altered rocks were discovered along a mineralized belt extending eastward from Cerro La Tiza through the Rio Gurabo Valley nearly to the Vieques Passage bordering the east coast of Puerto Rico. Other zones were discovered north and south of this belt and still others were found circumventing the San Lorenzo batholith. The most abundant minerals of the mineralized zone can be exploited for economic utilization in Puerto Rico. Alunite can be utilized in the manufacture of aluminum sulfate for water purification. It can also be used in the manufacture of alumina refractory materials. Pyrophyllite can be used as a carrier for insecticides and fungicides. It can also be utilized for the manufacture of ceramic products, as a filler in the soap industry and as a carrier for paint pigments. Kaolinite can be used in the ceramic industry and in the manufacture of glass as a substitute for feldspar. Halloysite might be utilized as a catalyst support in the cracking of petroleum. Tonnages of reserve ore on Cerro La Tiza are calculated to be 1,590,000 inferred short tons (1,440,000,000 inferred metric tons) of mixed minerals. These tonnages are based on the assumption that the depth of the mineralized zone is one-half of the exposed width. The deposit is well situated for open pit mining, but because of the existing cover of earth-rock debris, soil foliage, exploration should proceed exploitation for better determination of the most promising areas containing the best concentrations of the minerals sought.

Cerro La Tiza↗

Uranium in pegmatites

Uranium and rare-earth minerals are common accessory minerals in pegmatite deposits. No domestic pegmatites have been found that are rich enough to support an economic mining operation for uranium alone; however, small quantities of uranium minerals may be recovered as by-products of feldspar or mica mining. Madagascar is the only country that has produced appreciable tonnages of uranium minerals from pegmatites.A review of the literature and observations in the domestic pegmatite districts show that the uranium and rare earth minerals generally occur in pegmatites or pegmatite units rich in potash feldspar. Recent mineralogical and structural studies of pegmatites by the U. S. Geological Survey indicate that, on the basis of geologic mapping, these units can be projected laterally and in depth with reasonable accuracy. In most places the mineral content of these units can be estimated with sufficient accuracy for development purposes.

New Mexico↗

Twenty-eighth annual report of the Director of the United States Geological Survey

The plan of operations for the last fiscal year, including an itemized statement of the appropriations, amounting to $1,758,720, with the allotments thereof, was approved by the Secretary of the Interior on July 10, 1906. The work of the various branches and divisions conformed to this plan, and a detailed statement of their operations may be found on later pages. On January 23 the former Director, Charles D. Walcott, was appointed to the position of Secretary of the Smithsonian Institution, and his resignation as Director was accepted by the President, becoming effective April 30, 1907. Mr. Walcott has been a member of the Survey since its organization, and the thirteen years of his service as the administrative head of the bureau cover the period of its greatest growth. At the beginning of his directorship Mr. Walcott disclaimed any desire to make radical changes in either the policy or the administration of the Survey as developed under his predecessors, King and Powell, but in his first report, the Director's sixteenth, he mentioned certain readjustments which he deemed desirable in order that the Survey might better meet the economic and educational needs of the country. It is noteworthy that, almost without exception, these improvements have been accomplished, and even more fully than as then outlined. Among these changes may be mentioned : The raising of the standard of the topographic maps, with the representation thereon of land subdivision lines, and the extension of exact leveling and primary triangulation; the placing of the entire topographic and geologic force within the classified service; the obtaining of authority from Congress to issue separates of the annual report in pamphlet form, thus permitting advance publication of chapters of the Mineral Resources report, as well as of papers on economic geology; the enlargement of the work of the divisions of hydrography, mineral resources, and geology, in the last case providing for reconnaissance surveys of regions of economic importance. Equally notable was the growth of the Survey under Mr. Walcott's administration, as shown by the increase in both the extent and the scope of its operations. The appropriations for the last fiscal year amounted to more than four times the total of those made thirteen years ago, and there was, of course, a corresponding increase in the amount of field and office work performed. The development of the relations between the Geological Survey and the public within the same period is measured by a more than fourfold increase in amount of official correspondence, nearly fourfold increase in number of printed pages in the various reports of the year, and a more than fivefold increase in copies of maps printed, while the total annual distribution of publications, books, and maps grew from less than 200,000 to nearly a million copies, the sales increasing from $2,100 to over $18,000. The extent to which the results of the work by this organization are now utilized by both the industrial world and the educational and scientific institutions furnishes the best index of the degree of success attained by Mr. Walcott and his colleagues.

Annual Report↗

Identification of mineral resources in Afghanistan—Detecting and mapping resource anomalies in prioritized areas using geophysical and remote sensing (ASTER and HyMap) data

As part of the U.S. Geological Survey (USGS) and Department of Defense Task Force for Business and Stability Operations (TFBSO) natural resources revitalization activities in Afghanistan (Peters and others, 2011), three new datasets have been collected, compiled, and analyzed. These data have been used to more fully evaluate the areas of interest (AOIs; fig. 1 ) where, on the basis of previous U.S.S.R. and Afghanistan studies, the opportunity for early economic development of a number of different mineral, commodity, and deposit types had been identified (Peters and others, 2007; Peters and others, 2011). The new data compilations include (1) regional magnetic and gravity data for use in the characterization of subsurface composition and structure (Sweeney and others, 2006a,b; Ashan and others, 2007; Sweeney and others, 2007; Ashan and others, 2008; Shenwary and others, 2011), (2) Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data to identify and evaluate surficial alteration patterns related to industrial minerals and other selected targets, and (3) HyMap imaging spectrometer data for characterization and mapping of surficial mineralogy (Cocks and others, 1998; Kokaly and others, 2008; Peters and others, 2011). These datasets have served as fundamental building blocks for the resource evaluation by Peters and others (2011). During the independent analysis of the geophysical, ASTER, and imaging spectrometer (HyMap) data by USGS scientists, previously unrecognized targets of potential mineralization were identified using evaluation criteria most suitable to the individual dataset. These anomalous zones offer targets of opportunity that warrant additional field verification. This report describes the standards used to define the anomalies, summarizes the results of the evaluations for each type of data, and discusses the importance and implications of regions of anomaly overlap between two or three of the datasets.

Open-File Report↗

Some suggested future directions of quantitative resource assessments

Future quantitative assessments will be expected to estimate quantities, values, and locations of undiscovered mineral resources in a form that conveys both economic viability and uncertainty associated with the resources. Historically, declining metal prices point to the need for larger deposits over time. Sensitivity analysis demonstrates that the greatest opportunity for reducing uncertainty in assessments lies in lowering uncertainty associated with tonnage estimates. Of all errors possible in assessments, those affecting tonnage estimates are by far the most important. Selecting the correct deposit model is the most important way of controlling errors because the dominance of tonnage-deposit models are the best known predictor of tonnage. Much of the surface is covered with apparently barren rocks and sediments in many large regions. Because many exposed mineral deposits are believed to have been found, a prime concern is the presence of possible mineralized rock under cover. Assessments of areas with resources under cover must rely on extrapolation from surrounding areas, new geologic maps of rocks under cover, or analogy with other well-explored areas that can be considered training tracts. Cover has a profound effect on uncertainty and on methods and procedures of assessments because geology is seldom known and geophysical methods typically have attenuated responses. Many earlier assessment methods were based on relationships of geochemical and geophysical variables to deposits learned from deposits exposed on the surface-these will need to be relearned based on covered deposits. Mineral-deposit models are important in quantitative resource assessments for two reasons: (1) grades and tonnages of most deposit types are significantly different, and (2) deposit types are present in different geologic settings that can be identified from geologic maps. Mineral-deposit models are the keystone in combining the diverse geoscience information on geology, mineral occurrences, geophysics, and geochemistry used in resource assessments and mineral exploration. Grade and tonnage models and development of quantitative descriptive, economic, and deposit density models will help reduce the uncertainty of these new assessments.

Diqiu Kexue - Zhongguo Dizhi Daxue Xuebao/Earth Sc↗

Economic geology and environmental characteristics of antimony deposits

Antimony is commonly listed as a critical mineral, particularly in the United States and European Union [1]. Its criticality, or supply risk, is derived from a combination of economic vulnerability, disruption potential of supply, and trade exposure [2].Disruption potential relates a country’s ability and willingness to supply a commodity. Commodities for which supply is concentrated in the fewest countries have the greatest potential for supply disruption, trade exposure, and economic vulnerability. In 2018, approximately 61% of the world production of antimony was mined from China, followed by Russia (20%) and Tajikistan (10%) [3] (Fig. 3.1). Several reviews of antimony as a critical mineral have been recently published [4, 5]. The uses of antimony can be divided into three main categories: metal products, non-metal uses, and flame retardants [5]. Most metallic antimony use is inlead-acid batteries. Antimony trioxide (Sb 2 O 3 ) combined with halogenated com-pounds is used as a fire retardant in plastics, fabrics, and other applications. Other non-metallic uses include as a catalyst for plastics, and in the glass industry. Emerging uses include data storage and novel photovoltaic cells. Recycling of batteries represents an important reuse of antimony, but other uses of antimony do not lend themselves to recycling. This chapter describes mineral deposit types that are primary sources of antimony, and environmental effects related to their mining. Antimony can be re-covered as either a primary commodity from some deposits or as a by product commodity from some gold or silver deposits. Environmental risks associated with antimony mining include those related to mining in general, such as the acid-generating potential of solid mine waste, and some issues specific to antimony, as described below.

Book chapter↗

Integrated science strategy for assessing and monitoring water availability and migratory birds for terminal lakes across the Great Basin, United States

Executive Summary In 2022, the U.S. Geological Survey (USGS) established the Saline Lake Ecosystems Integrated Water Availability Assessment (IWAAs) to monitor and assess the hydrology of terminal lakes in the Great Basin and the migratory birds and other wildlife dependent on those habitats. Scientists from across the USGS (with specialties in water quantity, water quality, limnology, avian biology, data science, landscape ecology, and science communication) formed the Saline Lake Ecosystems IWAAs Team. The team has developed this regional strategic science plan to guide data collection and assessment activities at terminal lakes in the Great Basin. The U.S. Congress requested the USGS to establish the Saline Lake Ecosystems IWAAs in response to historically low water levels at terminal lakes and associated wetlands across the Great Basin. Not all Great Basin terminal lakes have high salinity; however, all terminal lakes occur in endorheic, closed, basins with no surface-water outflow. Low lake levels across the Great Basin are the result of increased water use for agriculture and municipalities, drought conditions, and a warming climate. Great Basin terminal lake water extents have decreased by as much as 90 percent over the last 150 years, and terminal lake wetlands have decreased in area by as much as 47 percent since 1984. Lake elevations and wetland areas are primarily supported by freshwater inputs from snowmelt feeding upgradient rivers, streams, and springs. These freshwater inputs have been severely reduced because of continued and increased surface-water diversions and surface-water capture through groundwater pumping for agriculture, mining, and public supply as well as unprecedented drought conditions and warming temperatures related to climate change. Water quality, specifically salinity, is highly variable for terminal lakes of the Great Basin, and this variability is a result of the balance between freshwater inflow and evaporation. Variability of salinity at each of the terminal lakes can be affected by lake morphology, hydrogeologic features of the basin, annual variability in weather patterns, and changes in upgradient water use. Hypersaline terminal lakes provide abundant food resources such as brine shrimp and brine flies that support nesting and migrating birds. The density and composition of invertebrates are closely tied to lake salinity. Increased salinity can exceed the tolerance of invertebrates, severely limiting their biomass. In contrast, decreased salinity can lead to altered invertebrate community composition, reducing the abundance of optimal avian prey resources. Great Basin terminal lake ecosystems, including open-water and adjacent aquatic and terrestrial environments, provide resources necessary to sustain many animal populations throughout the year. Although a variety of taxa use terminal lakes, these ecosystems are of acute importance for the millions of migratory waterbirds (for example, shorebirds, wading birds, and waterfowl) dependent on the network of terminal lakes and their associated wetlands. Migratory birds transiting the Pacific and Central Flyways use Great Basin terminal lake ecosystems throughout the year to feed, nest, and transit between wintering and breeding ranges. As such, successful conservation of birds and their habitats requires coordinated management of water and habitats across the Great Basin network of terminal lakes and wetlands. The linkages between water availability and ecosystem vulnerability of terminal lakes in the Great Basin are not well understood. The vulnerability of terminal lakes is related to the factors driving change and adaptive capacity of the lake ecosystem. Saline lake ecosystems are vulnerable when changes in water quantity affect ecosystem function. Water quantity affects salinity, which affects food webs and habitat; these linkages can be investigated with water-quality and food web monitoring. Water quantity also affects inundated habitat, which can be quantified through remote sensing. It is necessary to quantify hydroclimatic and water use controls on water availability to terminal lakes to assess the response of the ecosystems. Remotely sensed data can provide a broad-scale and long-term synoptic view of terminal lake hydrologic characteristics, but ground observations are required to interpret changes in water quality and ecological functions. Some terminal lake basins have ongoing monitoring and modeling efforts within the Great Basin (for example, Great Salt Lake, Carson River Basin), yet most monitoring locations are hydrologically upgradient and too far away from lake inflows to provide an accurate assessment of hydrological trends for the lake ecosystems. Other terminal lakes have no long-term hydrological monitoring in their respective watersheds (for example, Lake Abert). Ecological data collection in the Great Basin is also insufficient to understand how many birds exist on the landscape, how birds use the mosaic of terminal-lake habitats as an interconnected system, and how Great Basin terminal lakes are linked to the larger continental system of the Pacific and Central Flyways. Across agencies and organizations, tracking bird movement, abundance, and diversity is inconsistent, with some lakes having once- or twice-a-year bird survey efforts and a few locations having more intensive ecological data-gathering efforts (for example, Great Salt Lake, Lake Abert). Bridging hydrological and ecological information gaps will improve understanding of the trends in water supply and water quality, habitat availability and usage, and impacts on vulnerable waterbird species, all of which would be used by managers in coordinated conservation of this unique network of terminal-lake habitats. The terminal lakes of the Great Basin are part of the Basin and Range physiographic province that extends from the Colorado Plateau on the east to the Sierra Nevada on the west, and from the Snake River Plain on the north to the Garlock fault and the Mojave block on the south. The Great Basin is larger than 650,000 square kilometers and encompasses most of the State of Nevada but also extends to western Utah, eastern California, southeastern Idaho, southwestern Wyoming, and southeastern Oregon. The climate is arid to semiarid with a hydrologic regime that is snowmelt dominated, providing as much as 75 percent of total annual runoff for the region. Terminal lakes of the Great Basin occupy the lowest areas of closed (endorheic) drainage basins, such that lake levels and water quality respond rapidly to surface-water inflow. Terminal lakes provide local and regional economic value to the States in the Great Basin, including mineral extraction, aquaculture, public works, and recreational uses. As an example, assessments of Great Salt Lake’s ecological health and economic impact find hemispheric importance for the former and regional importance for the latter. Great Salt Lake creates about 7,000 jobs and $2 billion of economic output per year, most of which would be lost with further declines in lake level. The objectives of this Science Strategy are threefold: (1) to identify how changing water availability affects the quality, diversity, and abundance of habitats supporting continental waterbird populations; (2) to highlight the scientific monitoring and assessment needs of Great Basin terminal lakes; and (3) to support coordinated management and conservation actions to benefit those ecosystems, migratory birds, and other wildlife. There are long-term hydrological, ecological, and societal challenges associated with terminal lakes ecosystems in the Great Basin. This Science Strategy benefits partners by providing a conceptual model, nested at different spatial extents, that identifies key scientific information needs to inform coordinated implementation of management and conservation plans within and among hydrologic basins to address these complex challenges.

California, Idaho, Nevada, Oregon, Utah, Wyoming↗

Titanium

Titanium is a mineral commodity that is essential to the smooth functioning of modern industrial economies. Most of the titanium produced is refined into titanium dioxide, which has a high refractive index and is thus able to impart a durable white color to paint, paper, plastic, rubber, and wallboard. Because of their high strength-to-weight ratio and corrosion resistance, titanium metal and titanium metal alloys are used in the aerospace industry as well as for welding rod coatings, biological implants, and consumer goods. Ilmenite and rutile are currently the principal titanium-bearing ore minerals, although other minerals, including anatase, perovskite, and titanomagnetite, could have economic importance in the future. Ilmenite is currently being mined from two large magmatic deposits hosted in rocks of Proterozoic-age anorthosite plutonic suites. Most rutile and nearly one-half of the ilmenite produced are from heavy-mineral alluvial, fluvial, and eolian deposits. Titanium-bearing minerals occur in diverse geologic settings, but many of the known deposits are currently subeconomic for titanium because of complications related to the mineralogy or because of the presence of trace contaminants that can compromise the pigment production process. Global production of titanium minerals is currently dominated by Australia, Canada, Norway, and South Africa; additional amounts are produced in Brazil, India, Madagascar, Mozambique, Sierra Leone, and Sri Lanka. The United States accounts for about 4 percent of the total world production of titanium minerals and is heavily dependent on imports of titanium mineral concentrates to meet its domestic needs. Titanium occurs only in silicate or oxide minerals and never in sulfide minerals. Environmental considerations for titanium mining are related to waste rock disposal and the impact of trace constituents on water quality. Because titanium is generally inert in the environment, human health risks from titanium and titanium mining are minimal; however, the processes required to extract titanium from titanium feedstock can produce industrial waste.

Professional Paper↗

Economics, helium, and the U.S. Federal Helium Reserve: Summary and outlook

In 2017, disruptions in the global supply of helium reminded consumers, distributors, and policy makers that the global helium supply chain lacks flexibility, and that attempts to increase production from the U.S. Federal Helium Reserve (the FHR) may not be able to compensate for the loss of one of the few major producers in the world. Issues with U.S. and global markets for helium include inelastic demand, economic availability of helium only as a byproduct, only 4–5 major producers, helium’s propensity to escape earth’s crust, an ongoing absence of storage facilities comparable to the FHR, and a lack of consequences for the venting of helium. The complex combination of these economic, physical, and regulatory issues is unique to helium, and determining helium’s practical availability goes far beyond estimating the technically accessible volume of underground resources. Although most of these issues have been analyzed since helium was recognized to be a valuable mineral commodity in the early 1900s, very few economic models have been developed that adequately consider the unique characteristics of helium and helium markets. In particular, there is a notable lack of recent empirical work to estimate the responsiveness of helium demand, supply, prices, and trade patterns to the ongoing drawdown and sale of helium reserves stored in the FHR. In general, existing models of helium either do not account for an oligopoly controlling supply, or they do not evaluate potential helium extraction and storage programs based on an intertemporal maximization of the value of the resource. Such models could be of very limited use to decision makers. This review found only one working paper with a helium market model that has incorporated both of these vital considerations. That and other economic studies along similar lines could be very useful in helping inform current helium policy discussions and decisions.

Natural Resources Research↗