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USGS2025

U.S. Geological Survey global seabed mineral resources

The U.S. Geological Survey (USGS) provides science and data on seabed mineral resources and ecosystems, as well as on the potential hazards associated with extraction. The Nation relies on minerals for infrastructure, technology, manufacturing, and energy production. Critical minerals are essential to the economic and national security of the United States and have a supply chain vulnerable to disruption. For decades, USGS scientific innovation has contributed to the delineation of seabed mineral resources, the mechanisms of seabed mineral formation, and the environmental impacts of resource extraction. Since 1962, the USGS has also led scientific inquiries into the potential for deep sea mining. By providing impartial science on seabed minerals and their environmental setting in the deep oceans, the USGS enables decision-makers to evaluate the best practices for mineral resource development.

Fact Sheet↗

USGS1972

Energy resources of the United States

Estimates are made of United States resources of coal, petroleum liquids, natural gas, uranium, geothermal energy, and oil from oil shale. The estimates, compiled by specialists of the U.S. Geological Survey, are generally made on geologic projections of favorable rocks and on anticipated frequency of the energy resource in the favorable rocks. Accuracy of the estimates probably ranges from 20 to 50 percent for identified-recoverable resources to about an order of magnitude for undiscovered-submarginal resources. The total coal resource base in the United States is estimated to be about 3,200 billion tons, of which 200-390 billion tons can be considered in the category identified and recoverable. More than 70 percent of current production comes from the Appalachian basin where the resource base, better known than for the United States as a whole, is about 330 billion tons, of which 22 billion tons is identified and recoverable. Coals containing less than 1 percent sulfur are the premium coals. These are abundant in the western coal fields, but in the Appalachian basin the resource base for low-sulfur coal is estimated to be only a little more than 100 billion tons, of which 12 billion tons is identified and recoverable. Of the many estimates of petroleum liquids and natural-gas resources, those of the U.S. Geological Survey are the largest because, in general, our estimates include the largest proportion of favorable ground for exploration. We estimate the total resource base for petroleum liquids to be about 2,900 billion barrels, of which 52 billion barrels is identified and recoverable. Of the total resource base, some 600 billion barrels is in Alaska or offshore from Alaska, 1,500 billion barrels is offshore from the United States, and 1,300 billion barrels is onshore in the conterminous United States. Identified-recoverable resources of petroleum liquids corresponding to these geographic units are 11, 6, and 36 billion barrels, respectively. The total natural-gas resource of the United States is estimated to be about 6,600 trillion cubic feet, of which 290 trillion cubic feet is identified and recoverable. In geographic units comparable to those for petroleum liquids, the resource bases are 1,400, 3,400, and 2,900 trillion cubic feet, and the identified-recoverable resources are 31, 40, and 220 trillion cubic feet, respectively. Uranium resources in conventional deposits, where uranium is the major product, are estimated at 1,600,000 tons of U3O8, of which 250,000 tons is identified and recoverable. A potential byproduct resource of more than 7 million tons of U3O8, is estimated for phosphate rock, but none of this resource is recoverable under present economic conditions. The resources of heat in potential geothermal energy sources are poorly known. The total resource base for the United States is certainly greater than 10 22 calories, of which only 2.5 ? 10 18 calories can be considered identified and recoverable at present. Oil shale is estimated to contain 26 trillion barrels of oil. None of this resource is economic at present, but if prices increase moderately, 160-600 billion barrels of this oil could be shifted into the identified-recoverable category.

Circular↗

USGS2020

Double exposure and dynamic vulnerability: Assessing economic well-being, ecological change and the development of the oil and gas industry in coastal Louisiana

The oil and gas industry has been a powerful driver of economic change in coastal Louisiana for the latter half of the 20th century and into the 21st. Yet, the overall impact of the industry on the economic well-being of host communities is varied, both spatially and temporally. While the majority of Louisiana’s oil and gas production now occurs offshore, processing the extracted product is an energy-intensive undertaking requiring an expansive network of land-based infrastructure. Despite the positive economic aspects of this development, there are also potential negatives posed to coastal ecosystems and to communities located adjacent to oil and gas infrastructure. This research utilizes a double exposure framework to explore the relationship between oil and gas infrastructure development, fish and shellfish habitat, and economic well-being in Louisiana’s coastal zone from 1950 to 2010. The approach followed four main steps: (1) Developing a hazardousness of place model to identify areas of magnified risk due to the combined hazards of multiple potential exposure sites related to the extraction and processing of crude oil and natural gas; (2) developing a model of ecological functioning to measure the ability of aquatic habitat to support key fish and shellfish species; (3) utilizing an integrated community economic well-being index to assess change on a decadal timescale; and (4) analyzing selected oil-dependent communities to illustrate how change processes occurring in different energy sectors result in differential outcomes. The results suggest that, for many communities, the dependence on the oil and gas industry has increased economic well-being but also increased sensitivity to natural and human-induced changes, including fluctuating economic conditions, environmental stress, coastal habitat destruction, and increasing social and economic pressures.

Louisiana↗

USGS2011

Deposit model for volcanogenic uranium deposits

Volcanism is a major contributor to the formation of important uranium deposits both close to centers of eruption and more distal as a result of deposition of ash with leachable uranium. Hydrothermal fluids that are driven by magmatic heat proximal to some volcanic centers directly form some deposits. These fluids leach uranium from U-bearing silicic volcanic rocks and concentrate it at sites of deposition within veins, stockworks, breccias, volcaniclastic rocks, and lacustrine caldera sediments. The volcanogenic uranium deposit model presented here summarizes attributes of those deposits and follows the focus of the International Atomic Energy Agency caldera-hosted uranium deposit model. Although inferred by some to have a volcanic component to their origin, iron oxide-copper-gold deposits with economically recoverable uranium contents are not considered in this model. The International Atomic Energy Agency's tabulation of volcanogenic uranium deposits lists 100 deposits in 20 countries, with major deposits in Russia, Mongolia, and China. Collectively these deposits are estimated to contain uranium resources of approximately 500,000 tons of uranium, which amounts to 6 percent of the known global resources. Prior to the 1990s, these deposits were considered to be small (less than 10,000 tons of uranium) with relatively low to moderate grades (0.05 to 0.2 weight percent of uranium). Recent availability of information on volcanogenic uranium deposits in Asia highlighted the large resource potential of this deposit type. For example, the Streltsovskoye district in eastern Russia produced more than 100,000 tons of uranium as of 2005; with equivalent resources remaining. Known volcanogenic uranium deposits within the United States are located in Idaho, Nevada, Oregon, and Utah. These deposits produced an estimated total of 800 tons of uranium during mining from the 1950s through the 1970s and have known resources of 30,000 tons of uranium. The most recent estimate of speculative resources proposed an endowment of 200,000 tons of uranium.

Open-File Report↗

USGS2025

Variable partitioning of lithium in rhyolitic melt during decompression and ascent

The partitioning behavior of Li in magmatic systems is increasingly being investigated due to the economic importance of Li in the transition to sustainable energy resources (e.g., batteries). However, at upper crustal pressures, it remains uncertain whether Li preferentially partitions into the vapor or liquid (brine) phase or remains in the silicate melt. This complicates our ability to determine where Li resides—silicate melt, minerals, or fluid phase—upon eruption, a crucial factor for understanding its postdepositional movement and concentration into a brine or volcano-sedimentary deposit. Here, we present a novel investigation into the behavior of Li within natural evolved melts during continuous magma decompression and ascent using melt embayments (open melt inclusions). Mineral-hosted melt embayments preserve records of the evolving composition of the exterior melt, including degassing pathways and ascent timescales, when paired with appropriate diffusion coefficients. Lithium concentration profiles were measured in quartz-hosted melt embayments from the rapidly quenched eruptive phases of five rhyolitic, caldera-forming eruptions to investigate the behavior of Li during magma decompression and ascent, where vapor partitioning and ascent dynamics were previously established by investigating H 2 O and CO 2 profiles. We find that in four systems, embayments contain lower interior Li concentrations than the coerupted melt inclusions; the fifth system contains the same Li concentrations in embayments and melt inclusions. However, many of these embayments contain gradients, with 84 % preserving Li enrichment near the melt-bubble interface, as compared to their interior concentration. We interpret these characteristics to represent two distinct stages of Li partitioning during magma decompression and ascent, in contrast to existing literature that proposes only one type of partitioning behavior. The first stage is interpreted as melt depletion of Li, likely driven by partitioning into an exsolved supercritical fluid phase, supported by the strong correlation between the extent of Li depletion and Cl concentration in the melt, as well as the decompression rate. This behavior then fundamentally shifts, where Li reenriches in the melt, postulated to be driven by the unmixing of the supercritical fluid phase at shallow pressures. For the one system that did not develop Li gradients through decompression, we attribute this to the lower values of Na and Cl in the melt, potentially inhibiting the partitioning of Li into a fluid phase. Importantly, the behavior of Li during decompression is not consistent within or between volcanic centers, highlighting the need for systematic experimental investigation in variable composition melts at pressures relevant to conduit dynamics. This knowledge would improve our ability to model Li profiles to understand magma decompression, and predict where Li resides (e.g., stored in volcanic glass, gas, or crystals) upon eruption prior to any later extraction.

Economic Geology↗

USGS2006

Afghan resource assessment fed positive outlook for exploration

Crude oil, natural gas and natural gas liquids/condensate resources are important for the redevelopment of Afghanistan's infrastructure. Improved living and economic conditions in Afghanistan require increasing the availability of energy particularly by exploitation of Afghanistan's petroleum resources. The four total petroleum systems are subdivided into units with homogeneous geologic traits and exploration efforts that include sufficiently homogeneous field-size populations for resource assessment. The greatest volume of undiscovered crude oil is estimated to be in the Afghanistan Eastern Suprasalt Thrusts and Folds Assessment Unit. The greatest volume of undiscovered natural gas is estimated to be in the Afghanistan Jurassic Evaporite Basin Subsalt Carbonates Assessment Unit.

Oil & Gas Journal↗

USGS2013

Development of the copper and molybdenum industries and the Armenian economy

Production of copper and molybdenum in Armenia is examined, with special emphasis on the location of major deposits, former and proposed future centers of processing, and contribution of metals exports to the country's foreign trade revenues. Particular emphasis is placed on the impacts on these industries of the disruption of economic ties resulting from the dissolution of the USSR and an economic crisis precipitated by a major earthquake, Armenia's tension with Azerbaijan over armed conflict in Nagorno-Karabakh and surrounding areas in Azerbaijan, an economic blockade imposed by Turkey and Azerbaijan, and a consequent severe energy crisis. The paper highlights developments in the mid-1990s in copper and molybdenum and in the recent expansion of trade relations with Iran.

Post-Soviet Geography and Economics↗

USGS2025

Geothermal potential of orphan oil and gas wells

The United States is estimated to have hundreds of thousands of orphan oil and gas wells. Orphan wells are abandoned wells that are both unremediated and have no responsible operator. While traditionally considered environmental and economic liabilities, orphan oil and gas wells may offer new opportunities in sustainable geothermal energy development. This study evaluates the potential of repurposing orphan wells for geothermal energy production. We analyzed more than 1.4 million bottom-hole temperature (BHT) records from oil and gas well logs to create corrected temperature-depth profiles in a grid across the United States. Total depth values, where available, in documented orphan wells from a U.S. Geological Survey (USGS) database were then correlated to these temperature-depth profiles to estimate a corrected BHT for each orphan well. The orphan wells were then categorized as having low (<90°C), moderate (90–150°C), and high (>150°C) geothermal potential, identifying them as wells in the U.S. that could be used to access geothermal resources. In addition, repurposing these wells could contribute to broader environmental and economic goals, including well remediation, rogue methane emissions reduction, and energy production. This study provides a framework for integrating inactive well inventories with geothermal resource assessments and further highlights the potential for orphan wells to play a transformative role in expanding geothermal energy capacity in the United States.

contiguous United States↗

USGS2013

Book review: Economic geology: Principles and practice: Metals, minerals, coal and hydrocarbons—Introduction to formation and sustainable exploitation of mineral deposits

This volume, available in both hardcover and paperback, is an English translation of the fifth edition of the German language text Mineralische und Energie-Rohstoffe. The book provides an extensive overview of natural resources and societal issues associated with extracting raw materials. The comprehensive list of raw materials discussed includes metals, industrial minerals, coal, and hydrocarbons. The book is divided into four parts: (1) “Metalliferous ore deposits,” (2) “Nonmetallic minerals and rocks,” (3) “Practice of economic geology,” and (4) “Fossil energy raw materials—coal, oil, and gas.” These sections are bound by a brief introduction and an extensive list of up-to-date references as well as an index. Each chapter begins with a concise synopsis and concludes with a summary that contains useful suggestions for additional reading. All figures are grayscale images and line drawings; however, several have been grouped together and reproduced as color plates. Also included is a companion website ( www.wiley.com/go/pohl/geology ) that contains additional resources, such as digital copies of figures, tables, and an expanded index, all available for download in easy-to-use formats. Economic Geology: Principles and Practice: Metals, Minerals, Coal and Hydrocarbons—Introduction to Formation and Sustainable Exploitation of Mineral Deposits. Walter l. Pohl. 2011. Wiley-Blackwell. Pp. 663. ISBN 978-1-4443-3663-4 (paperback).

Economic Geology↗

USGS2017

Assessing U.S. coal resources and reserves

The U.S. Coal Resources and Reserves Assessment Project, as part of the U.S. Geological Survey (USGS) Energy Resources Program, conducts systematic, geology-based, regional assessments of significant coal beds in major coal basins in the United States. These assessments detail the quantity, quality, location, and economic potential of the Nation’s remaining coal resources and reserves and provide objective scientific information that assists in the formulation of energy strategies, environmental policies, land-use management practices, and economic projections.

Fact Sheet↗

USGS1986

USGS research on energy resources, 1986; program and abstracts

The extended abstracts in this volume are summaries of the papers presented orally and as posters in the second V. E. McKelvey Forum on Mineral and Energy Resources, entitled "USGS Research on Energy Resources-1986." The Forum has been established to improve communication between the USGS and the earth science community by presenting the results of current USGS research on nonrenewable resources in a timely fashion and by providing an opportunity for individuals from other organizations to meet informally with USGS scientists and managers. It is our hope that the McKelvey Forum will help to make USGS programs more responsive to the needs of the earth science community, particularly the mining and petroleum industries, and Win foster closer cooperation between organizations and individuals. The Forum was named after former Director Vincent E. McKelvey in recognition of his lifelong contributions to research, development, and administration in mineral and energy resources, as a scientist, as Chief Geologist, and as Director of the U.S. Geological Survey. The Forum will be an annual event, and its subject matter will alternate between mineral and energy resources. We expect that the format will change somewhat from year to year as various approaches are tried, but its primary purpose will remain the same: to encourage direct communication between USGS scientists and the representatives of other earth-science related organizations. Energy programs of the USGS include oil and gas, coal, geothermal, uranium-thorium, and oil shale; work in these programs spans the national domain, including surveys of the offshore Exclusive Economic Zone. The topics selected for presentation at this McKelvey Forum represent an overview of the scientific breadth of USGS research on energy resources. They include aspects of petroleum occurrence in Eastern United States rift basins, the origin of magnetic anomalies over oil fields, accreted terranes and energy-resource implications, coal quality, geothermal energy sources, integrated geology and chemistry in uranium-deposit studies, and interpretations of sea-floor geology seen in reconnaissance-scale sidescan-sonar mosaics of the Gulf of Mexico and west coast Exclusive Economic Zone. Data are presented that are being used in building models of geothermal energy settings, basin histories, and the occurrence of energy resources. In addition to the technical sessions presenting the results of USGS research, each congressionally mandated USGS Mineral Resource Program has a display outlining plans and progress. We are all excited about this continuing opportunity to disseminate and discuss our research with our colleagues in industry and academia, and we welcome your suggestions on improving this series of Forums.

Circular↗

USGS1997

The Coastal and Marine Geology Program of the U.S. Geological Survey

Nearly half of all Americans live within an hour's drive of an ocean, the Gulf of Mexico, or the Great Lakes. The U.S. coastal oceans are an economically vital transportation, commercial and recreational resource. They provide food, energy, and minerals for the entire Nation: on a global scale, they harbor critical habitat for important animal and plant species.

Fact Sheet↗

USGS1979

The Yampa River basin, Colorado and Wyoming : a preview to expanded coal-resource development and its impacts on regional water resources

Expanded coal production and conversion in the Yampa River basin , Colorado and Wyoming, may have substantial impacts on water resources, environmental amenities, and socioeconomic conditions. Preliminary results of a 3-year basin assessment by the U.S. Geological Survey are given for evaluation of surface- and ground-water resources using available data, modeling analysis of waste-load capacity of a Yampa River reach affected by municipal wastewater-treatment plant effluents, and semiquantitative descriptions of ambient air- and water-quality conditions. Aspects discussed are possible constraints on proposed development due to basin compacts and laws regulating water resources, possible changes in environmental-control regulations, and policies on energy-resource leasing and land use that will influence regional economic development. (Woodard-USGS)

Water-Resources Investigations Report↗

USGS2022

Impacts of ocean-atmosphere teleconnection patterns on the south-central United States

Recent research has linked the climate variability associated with ocean-atmosphere teleconnections to impacts rippling throughout environmental, economic, and social systems. This research reviews recent literature through 2021 in which we identify linkages among the major modes of climate variability, in the form of ocean-atmosphere teleconnections, and the impacts to temperature and precipitation of the South-Central United States (SCUSA), consisting of Arkansas, Louisiana, New Mexico, Oklahoma, and Texas. The SCUSA is an important areal focus for this analysis because it straddles the ecotone between humid and arid climates in the United States and has a growing population, diverse ecosystems, robust agricultural and other economic sectors including the potential for substantial wind and solar energy generation. Whereas a need exists to understand atmospheric variability due to the cascading impacts through ecological and social systems, our understanding is complicated by the positioning of the SCUSA between subtropical and extratropical circulation features and the influence of the Pacific and Atlantic Oceans, and the adjacent Gulf of Mexico. The Southern Oscillation (SO), Pacific-North American (PNA) pattern, North Atlantic Oscillation (NAO) and the related Arctic Oscillation (AO), Atlantic Multidecadal Oscillation/Atlantic Multidecadal Variability (AMO/AMV), and Pacific Decadal Oscillation/Pacific Decadal Variability (PDO/PDV) have been shown to be important modulators of temperature and precipitation variables at the monthly, seasonal, and interannual scales, and the intraseasonal Madden-Julian Oscillation (MJO) in the SCUSA. By reviewing these teleconnection impacts in the region alongside updated seasonal correlation maps, this research provides more accessible and comparable results for interdisciplinary use on climate impacts beyond the atmospheric-environmental sciences.

Arkansas, Louisiana, New Mexico, Oklahoma, Texas↗

USGS1981

Economics and coal resource appraisal: strippable coal in the Illinois Basin ( USA)

Coal-resource appraisals generally describe the location and general characteristics of coal beds. Estimates are made of the average overburden depth (depth of the coal bed below the surface), bed thickness, and perhaps certain chemical properties of the coal [1]. Although such resource compilations represent an important initial step, neither they nor current estimates provide sufficient information to determine the costs of alternative options for National energy policy. Because coal is expected to provide an increasing part of future overall U.S. energy supply, it is crucial for long term planning that coalresource appraisals convey sufficient information regarding the degree of economic resource scarcity (escalation of unit costs for mining remaining deposits as the best deposits in an area are mined out) expected as coal consumption increases. However, assumptions embodied in most large-scale models of coal supply [13; 20] imply that the coal reserves that exist can be commercially produced as needed. As demonstrated by the embargo of 1973-1974 and more recent difficulties in obtaining crude oil, even a slight temporary commodity shortfall will result in significant economic losses when the commodity supplies a large proportion of the total energy used by an economy. For the United States, crude oil resource estimates did not give warning of a decline in domestic petroleum product. In this paper we argue that coal-resource estimates, as they are now made, will not give warning of future supply difficulties. A method for incorporating an economic dimension into appraisals of strippable coal resources is presented and is applied to a major U.S. coal-producing region, the Illinois part of the Illinois basin. Illinois accounts for nearly 70% of the demonstrated strippable coal reserve base of the Illinois basin [12]. In particular, a long-run incremental cost function (that is unit costs vs. cumulative reserves extracted) is estimated for strippable coal in Illinois. The estimated cost function exhibits an initial range over which costs increase at a constant rate-followed by a range where costs increase very rapidly and the function becomes quite inelastic. This long-run incremental cost function is significant for two reasons. Comparison of the demonstrated reserve base for strippable coal (14.8 billion tons) with cumulative production (since 1920 of 1.1 billion tons) might suggest that future depletion will not be significant when, in fact, the cost function presented here indicates otherwise. Because the only states having more reserves of strippable coal than Illinois are Montana and Wyoming [18], these results have implications for national coal-resource appraisal. Secondly, most models used to study the effects of alternative public policies in coal markets are static in nature [15; 16] and cannot consider the effects of increasing costs. Furthermore, models which are multi-period in nature [11; 13] appear to have little empirical basis for their assumptions regarding the escalation of production costs resulting from depletion. The plan of the paper is as follows. First a description of the analytical approach for constructing the long-run incremental cost-reserve function is discussed. Following this, the descriptions of the Illinois basin and the basic physical data are presented. In the concluding section, the main results are presented and their implications are explored

Southern Economic Journal↗

USGS1987

Prospects for heavy crude oil development

The problems of utilizing heavy crude oil and natural bitumens centre on their high viscosity which makes them difficult to produce, store, transport, and refine. These factors are reflected in costs. World reserves are substantial, however, perhaps as much as 7 trillion† barrels estimated to represent 0·9 trillion barrels of recoverable oil. Nearly 2·1 trillion barrels of heavy crude oil, more than 50% of the world's total reserve, are located in Venezuela largely in the Orinoco Oil Belt. About 75% of the natural bitumen, 2·6 trillion barrels, is located in Canada in the Athabasca, Cold Lake, and Peace River areas of Alberta. Most of the estimated undiscovered heavy crude oil in the world, approximately 630 billion barrels, is outside the US and Canada. Data required to determine the cost of finding natural bitumen and heavy oil are roughly the same as for other mineral commodities. Similarly for recovery costs. The variables are so extensive that dollar amounts have little meaning without qualification. Recovery depends on depth below surface. Near-surface deposits are recovered by mechanical mining. Deeper deposits must be won by thermal means. Transportation by pipeline is feasible only if the viscosity is lowered by partial upgrading, heating, or by the use of diluents. Part of the high cost of refining results from the major investment required for the large installations that are needed for economic rates of production.

Energy Exploration & Exploitation↗

USGS2011

Wind energy in the United States and materials required for the land-based wind turbine industry from 2010 through 2030

The generation of electricity in the United States from wind-powered turbines is increasing. An understanding of the sources and abundance of raw materials required by the wind turbine industry and the many uses for these materials is necessary to assess the effect of this industry's growth on future demand for selected raw materials relative to the historical demand for these materials. The U.S. Geological Survey developed estimates of future requirements for raw (and some recycled) materials based on the assumption that wind energy will supply 20 percent of the electricity consumed in the United States by 2030. Economic, environmental, political, and technological considerations and trends reported for 2009 were used as a baseline. Estimates for the quantity of materials in typical "current generation" and "next generation" wind turbines were developed. In addition, estimates for the annual and total material requirements were developed based on the growth necessary for wind energy when converted in a wind powerplant to generate 20 percent of the U.S. supply of electricity by 2030. The results of the study suggest that achieving the market goal of 20 percent by 2030 would require an average annual consumption of about 6.8 million metric tons of concrete, 1.5 million metric tons of steel, 310,000 metric tons of cast iron, 40,000 metric tons of copper, and 380 metric tons of the rare-earth element neodymium. With the exception of neodymium, these material requirements represent less than 3 percent of the U.S. apparent consumption for 2008. Recycled material could supply about 3 percent of the total steel required for wind turbine production from 2010 through 2030, 4 percent of the aluminum required, and 3 percent of the copper required. The data suggest that, with the possible exception of rare-earth elements, there should not be a shortage of the principal materials required for electricity generation from wind energy. There may, however, be selective manufacturing shortages if the total demand for raw materials from all markets is greater than the available supply of these materials or the capacity of industry to manufacture components. Changing economic conditions could also affect the development schedule of anticipated capacity.

Scientific Investigations Report↗

USGS2021

Greater Yellowstone climate assessment: Past, present, and future climate change in the greater Yellowstone watersheds

The Greater Yellowstone Area (GYA) is one of the last remaining large and nearly intact temperate ecosystems on Earth. GYA was originally defined in the 1970s as the Greater Yellowstone Ecosystem, which encompassed the minimum range of the grizzly bear. The boundary now includes about 22 million acres (8.9 million ha) in northwestern Wyoming, south central Montana, and eastern Idaho (Figure ES-1). Two national parks, five national forests, three wildlife refuges, 20 counties, and state and private lands lie within the GYA boundary (Figure ES-1). The Tribal Nations of the Eastern Shoshone, Northern Arapaho, Apsa´alooke/Crow, Northern Cheyenne, Shoshone, and Bannock have reservations in and near the Greater Yellowstone Area, and 27 Tribes are formally recognized to have historical connections to the lands and resources of the region. Natural resources sensitive to climate change connect many of the major economic activities of the GYA, including tourism and recreation, agriculture, and energy development.

Idaho, Montana, Wyoming↗