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USGS2004

Geologic history of natural coal-bed fires, Powder River basin, USA

Coal-bed fires ignited by natural processes have baked and fused overlying sediments to form clinker, a hard red or varicolored rock, through much of the northern Great Plains of the United States (USA). The gently dipping coal beds in the region burn when regional downwasting brings them above the local water table. The resulting clinker forms a rim along the exposed edge of the coal bed in an ongoing process through geologic time. The resistant clinker is left capping buttes and ridges after the softer unbaked strata erode away. Clinker outcrops cover more than 4100 km2 in the Powder River basin (PRB), which lies in Wyoming (WY) and Montana (MT). The clinker in place records tens of billions of tons of coal that have burned, releasing gases into the atmosphere. The amount of clinker that has eroded away was at least an order of magnitude greater than the clinker that remains in place. Fission-track and uranium-thorium/ helium ages of detrital zircon crystals in clinker, and paleomagnetic ages of clinker, show that coal beds have burned naturally during at least the past 4 million years (Ma). The oldest in-place clinker that has been dated, collected from a high, isolated, clinker-capped ridge, has a fission track age of 2.8??0.6 Ma. Evidence of erosion and downcutting is also preserved by clinker clasts in gravel terraces. One clinker boulder in a terrace 360 m above the Yellowstone River has a fission track age of 4.0??0.7 Ma. Coal-bed fires are caused by lightning, wildfires, spontaneous combustion, or human activity on coal outcrops and in mines. Miners, government agencies, and ranchers have extinguished thousands of coal bed fires, but natural ignition continues where fresh coal has access to air. At any given time, hundreds of fires, mostly small, are burning. In the Powder River basin, the total amount of coal burned by natural fires in the last 2 Ma is one to two orders of magnitude greater than the total amount of coal removed by mining in the past century. However, current annual rates of coal mining are three to four orders of magnitude greater than estimated prehistoric annual rates of coal consumption by natural fires. ?? 2004 Published by Elsevier B.V.

International Journal of Coal Geology↗
USGS1952

Magnetite deposits and magnetic anomalies of the Brandy Brook and Silver Pond belts, St. Lawrence County, New York

This report sets forth the geology and economic possibilities of the Brandy Brook and Silver Pond belts of magnetic anomalies, Cranberry Lake quadrangle, St. Lawrence County, northwestern New York. each belt contains a known magnetite deposit, partly explored through diamond drilling by the U.S. Bureau of Mines. The Brandy Brook Northwest deposit is a body of low-grade to medium-grade ore, possibly of lathlike shape. The Silver Pond deposit has no commercial interest at the moment. One of more promising magnetic anomalies remain to be tested by drilling.

New York↗
USGS2012

Simulated flow of groundwater and brine from a flooded salt mine in Livingston County, New York, and effects of remedial pumping on an overlying aquifer

Two ceiling collapses in the Retsof salt mine near Geneseo in upstate New York in spring 1994 resulted in the upward propagation of two columns of rubble through 600 feet of overlying shale and carbonate bedrock. This upward propagation formed a hydraulic connection between the lower confined aquifer (LCA) and the mine and allowed water from the aquifer and bedrock fracture zones that intersected the rubble columns to flow into the mine at a rate of 18,000 gallons per minute (gal/min) . All salt mining ceased in September 1995, and the mine was completely flooded by January 1996. The flow of water from the lower confined aquifer into the mine caused widespread drawdowns, and water levels in the aquifer declined by as much as 400 feet near the collapse area and by more than 50 feet at wells 7 miles to the north and south. Within 3 to 4 weeks of the collapses, water levels in about a dozen domestic and industrial wells had declined severely, and some wells went dry. Water levels in at least 58 wells in the lower and middle confined aquifers were affected by mine flooding. Groundwater in the upper unconfined aquifer and surface water in streams were unaffected by water-level drawdown, but channels of the Genesee River and Beards Creek were altered by land subsidence related to the mine collapse. Water levels recovered from 1996 through 2006, but the mine is now filled with about 15 billion gallons of saturated halite brine. The weight of the overlying rock and sediment is expected to cause the salt beds to deform and fill the mine cavity during the next several hundred years; this in turn could displace as much as 80 percent of the brine and cause it to move upward through the rubble chimneys, rendering the LCA unusable as a source of water supply. Saline water was detected in the LCA in 2002 but was found to be derived primarily from fractures in the limestone and shale units between the mine and the LCA, rather than from the mine. In September 2006, the mine company began a brine-mitigation project that entailed pumping five wells finished in limestone and shale units within the collapse areas to alter the flow gradient and thereby prevent further movement of brine and saline water into the LCA. The pumped brine was routed to an onsite desalination plant. At the same time, the U.S. Geological Survey (USGS) began a study in cooperation with the New York State Office of the Attorney General to construct numerical models to analyze the groundwater chemistry and delineate the directions of flow. Specific objectives of the study were to: * Assess the sources of salinity within the collapse area and identify the factors that control the movement and mixing of freshwater, saline waters from fracture zones, and brine; * Evaluate the likelihood that the pumping will induce anhydrite dissolution and lead to continued land subsidence; * Construct variable-density groundwater flow models to predict the effect of remedial pumping on salinity within the LCA; * Evaluate the effectiveness of remedial pumping in preventing the movement of saline water into the LCA; and * Predict the extent of brine migration 8 years after a hypothetical shutdown of all pumping in 2008. This report (1) summarizes the hydrogeologic setting and effects of mine flooding, (2) describes the geochemical and variable-density model simulations and their principal results, (3) discusses the implications of (a) continued pumping and desalination to protect the LCA and (b) a full shutdown of pumping after 2008, and (4) suggests further research that could lead to refinement of model predictions. Additional information may be found in Yager and others (2001 and 2009). These reports can be accessed at http://pubs.usgs.gov/pp/pp1611/ and http://pubs.usgs.gov/pp/pp1767/, respectively. A summary of simulation results can be accessed at http://ny.water.usgs.gov/projects/Coram/seawat/seawat.html.

New York↗
USGS1952

Geology of the Alaska-Juneau lode system, Alaska

The Alaska-Juneau lode system for many years was one of the worlds leading gold-producing areas. Total production from the years 1893 to 1946 has amounted to about 94 million dollars, with principal values in contained gold but with some silver and lead values. The principal mine is the Alaska-Juneau mine, from which the lode system takes its name. The lode system is a part of a larger gold-bearing belt, generally referred to as the Juneau gold belt, along the western border of the Coast Range batholith. The rocks of the Alaska-Juneau lode system consist of a monoclinal sequence of steeply northeasterly dipping volcanic, state, and schist rocks, all of which have been metamorphosed by dynamic and thermal processes attendant with the intrusion of the Coast Range batholith. The rocks form a series of belts that trend northwest parallel to the Coast Range. In addition to the Coast Range batholith lying a mile to the east of the lode system, there are numerous smaller intrusives, all of which are sill-like in form and are thus conformable to the regional structure. The bedded rocks are Mesozoic in age; the Coast Range batholith is Upper Jurassic and Lower Cretaceous in age. Some of the smaller intrusives pre-date the batholith, others post-date it. All of the rocks are cut by steeply dipping faults. The Alaska-Juneau lode system is confined exclusively to the footwall portion of the Perseverance slate band. The slate band is composed of black slate and black phyllite with lesser amounts of thin-bedded quartzite. Intrusive into the slate band are many sill-like bodies of rocks generally referred to as meta-gabbro. The gold deposits of the lode system are found both within the slate rocks and the meta-gabbro rocks, and particularly in those places where meta-gabbro bodies interfinger with slate. Thus the ore bodies are found in and near the terminations of meta-gabbro bodies. The ore bodies are quartz stringer-lodes composed of a great number of quartz veins from 6 inches to 3 feet wide and extending along their strike and dip for several tens to hundreds of feet. In addition to quartz, the only other vein gangue mineral is ankerite. It occurs in small amounts along the borders of the quartz veins. Metallic vein minerals, in addition to native gold, are, in order of decreasing abundance, pyrrhotite, galena, sphalerite, and arsenopyrite. In the aggregate the metallic minerals comprise only 1 to 2 percent of the total amount of vein material. The wall rock, particularly the meta-gabbro, was profoundly altered by the vein-forming processes. The principal effects on the meta-gabbro were the addition of large amounts of soda, potash, titanium, carbon dioxide, and phosphorous, and the removal of considerable quantities of iron, magnesia, lime, and combined water. Silica also may have been decreased. The mineralogical changes involved in the alteration were the development of biotite and ankerite at the expense of original hornblende and feldspar, resulting in a brown-colored biotite- and ankerite-rich rock. The slates are relatively unaffected by the vein-forming processes. Because of their small size, relatively low grade, and discontinuity, no attempt has been made to mine any individual vein. The prevailing practice has been to mine large blocks of ground by a system of modified block-caving, followed by hand sorting to remove the barren country rock from the gold-bearing quartz prior to milling.

Open-File Report↗
USGS2006

Sedimentation and Occurrence and Trends of Selected Chemical Constituents in Bottom Sediment, Empire Lake, Cherokee County, Kansas, 1905-2005

For about 100 years (1850-1950), the Tri-State Mining District in parts of southeast Kansas, southwest Missouri, and northeast Oklahoma was one of the primary sources of lead and zinc ore in the world. The mining activity in the Tri-State District has resulted in substantial historical and ongoing input of cadmium, lead, and zinc to the environment including Empire Lake in Cherokee County, southeast Kansas. The environmental contamination caused by the decades of mining activity resulted in southeast Cherokee County being listed on the U.S. Environmental Protection Agency's National Priority List as a superfund hazardous waste site in 1983. To provide some of the information needed to support efforts to restore the ecological health of Empire Lake, a 2-year study was begun by the U.S. Geological Survey in cooperation with the U.S. Fish and Wildlife Service and the Kansas Department of Health and Environment. A combination of sediment-thickness mapping and bottom-sediment coring was used to investigate sediment deposition and the occurrence of cadmium, lead, zinc, and other selected constituents in the bottom sediment of Empire Lake. The total estimated volume and mass of bottom sediment in Empire Lake were 44 million cubic feet and 2,400 million pounds, respectively. Most of the bottom sediment was located in the main body and the Shoal Creek arm of the reservoir. Minimal sedimentation was evident in the Spring River arm of the reservoir. The total mass of cadmium, lead, and zinc in the bottom sediment of Empire Lake was estimated to be 78,000 pounds, 650,000 pounds, and 12 million pounds, respectively. In the bottom sediment of Empire Lake, cadmium concentrations ranged from 7.3 to 76 mg/kg (milligrams per kilogram) with an overall median concentration of 29 mg/kg. Compared to an estimated background concentration of 0.4 mg/kg, the historical mining activity increased the median cadmium concentration by about 7,200 percent. Lead concentrations ranged from 100 to 950 mg/kg with an overall median concentration of 270 mg/kg. Compared to an estimated background concentration of 33 mg/kg, the median lead concentration was increased by about 720 percent as a result of mining activities. The range in zinc concentrations was 1,300 to 13,000 mg/kg with an overall median concentration of 4,900 mg/kg. Compared to an estimated background concentration of 92 mg/kg, the median zinc concentration was increased by about 5,200 percent. Within Empire Lake, the largest sediment concentrations of cadmium, lead, and zinc were measured in the main body of the reservoir. Within the Spring River arm of the reservoir, increased concentrations in the downstream direction likely were the result of tributary inflow from Short Creek, which drains an area that has been substantially affected by historical lead and zinc mining. Compared to nonenforceable sediment-quality guidelines, all Empire Lake sediment samples (representing 21 coring sites) had cadmium concentrations that exceeded the probable-effects guideline (4.98 mg/kg), which represents the concentration above which toxic biological effects usually or frequently occur. With one exception, cadmium concentrations exceeded the probable-effects guideline by about 180 to about 1,400 percent. With one exception, all sediment samples had lead concentrations that exceeded the probable-effects guideline (128 mg/kg) by about 10 to about 640 percent. All sediment samples had zinc concentrations that exceeded the probable-effects guideline (459 mg/kg) by about 180 to about 2,700 percent. Overall, cadmium, lead, and zinc concentrations in the bottom sediment of Empire Lake have decreased over time following the end of lead and zinc mining in the area. However, the concentrations in the most recently deposited bottom sediment (determined for 4 of 21 coring sites) still exceeded the probable-effects guideline by about 440 to 640 percent for cadmium, about 40 to 80 percent for lead, and about 580

Scientific Investigations Report↗
USGS2014

Coal and coalbed-methane resources in the Appalachian and Black Warrior basins: maps showing the distribution of coal fields, coal beds, and coalbed-methane fields

The maps contained in this chapter show the locations of coal fields, coal beds assessed by the U.S. Geological Survey (USGS) in 2000, and coalbed-methane fields in the central and southern Appalachian basin study areas, which include the coal-producing parts of the Black Warrior basin. The maps were compiled and modified from a variety of sources such as Tully (1996), Northern and Central Appalachian Basin Coal Regions Assessment Team (2001), Hatch and others (2003), Milici (2004), and unpublished data from the State geological surveys of Pennsylvania, West Virginia, Virginia, and Alabama. The terms “coalbed methane” and “coal-bed gas” are used interchangeably in this report. All of the figures are located at the end of this report. The Appalachian basin historically has been subdivided into three coal regions on the basis of regional geologic structure and stratigraphy: the northern region in western Pennsylvania, eastern Ohio, western Maryland, and northern West Virginia; the central region in west-central and southwestern West Virginia, eastern Kentucky, northern Tennessee, and southwestern Virginia; and the southern region in southern Tennessee, northern Alabama, and northwestern Georgia. The Appalachian basin is one of the most important coal-producing regions in the Nation and the world, and coal has been mined there throughout the last three centuries. The coal is primarily used within the Eastern United States for electrical power generation, but some of it is suitable for metallurgical uses. In 2008, the Appalachian basin produced about 320 million short tons of coal from 1,278 underground and surface coal mines (Energy Information Agency, 2009a). Coalbed-methane production in the Appalachian basin coal regions is an increasingly important resource. In 2008, 247 billion cubic feet (bcf) of coalbed methane was produced in the basin from Alabama (107 bcf), Virginia (101 bcf), West Virginia (28 bcf), and Pennsylvania (11 bcf) (Energy Information Agency, 2009b). Coalbed-methane exploration is ongoing in all of the States in the Appalachian basin coal regions, and production is expected to increase. The study area for most reports in this volume is the Appalachian basin. The term “Appalachian basin study area” (shortened from “Appalachian basin geologic framework study area”) includes all of the Appalachian Basin Province (Province 67) and part of the neighboring Black Warrior Basin Province (Province 65) of Dolton and others (1995). The boundaries for these two provinces and the study area are shown on figure 1.

Appalachian basin↗
USGS1985

Geology of the Brick Flat massive sulfide body, Iron Mountain cluster, West Shasta district, California

The Brick Flat massive sulfide body is one of a group of 8 individual bodies that constitute the Iron Mountain cluster in the S part of the West Shasta district. Before they were separated by postmineral faulting, 5 of the 8 sulfide bodies formed a single large deposit about 1375 m long with a mass of some 23 million metric tons. The pyritic Brick Flat sulfide body is one of the 5 faulted segements of this deposit. The Brick Flat massive sulfide lies within medium phenocryst rhyolite that is characteristic of the ore-bearing middle unit of the Balaklala Rhyolite. It is interpreted to be downfaulted a vertical distance of 75 to 85 m from the Old Mine sulfide-gossan orebody along the N-dipping Camden South fault. It is bounded in turn on its N side by another parallel fault, the Camden North, which drops the orebody down another 75 m to the level of the Richmond orebody. -from Author

Economic Geology↗
USGS2019

Coal geology and assessment of resources and reserves in the Little Snake River Coal Field and Red Desert Assessment Area, Greater Green River Basin, Wyoming

The U.S. Geological Survey is studying regional-scale assessments of resources and reserves of primary coal beds in the major coal bed basins in the United States to help formulate policy for Federal, State, and local energy and land use. This report summarizes the geology and coal resources and reserves in the Little Snake River coal field and Red Desert assessment area in the Greater Green River Basin, southwestern Wyoming. These areas are contiguous and referred to as the “assessment area” in this report. The assessment area covers about 2,300 square miles of the eastern section of the 15,400-square-mile Greater Green River Basin. This area was prioritized for assessment because no comprehensive resource assessment had previously been completed in the area; abundant, previously unavailable drill hole data from cooperators and stakeholders became available; and there are active coal mines in the Greater Green River Basin area producing from some of the same formations as those found in the assessment area. Coal-bearing Eocene, Paleocene, and Upper Cretaceous formations have a composite thickness of more than 11,000 feet in the assessment area. Stratigraphic sequences that contain multiple coal beds within a formation or member are referred to as coal zones in this report. Paleogene coal beds are found within coal zones in the Eocene Wasatch Formation and the Paleocene Fort Union Formation. Cretaceous coal beds are within coal zones in the Lance, Almond, and Allen Ridge Formations. A total of 4,214 drill holes and measured sections were used to construct a geologic database for this assessment. From these data, 7 coal zones containing 55 individual coal beds were identified. Not all 55 coal beds were assessed; only those beds that were at least 3 feet thick and had at least a 2-square-mile areal extent were considered. Using a geology-based assessment methodology, the U.S. Geological Survey estimated original, available, and recoverable coal resources for 33 coal beds that met those criteria. An original resource of 73.2 billion short tons of coal was calculated for the 33 coal beds that met the criteria in the assessment area. To be considered extractable by surface mining methods, coal beds had to be equal to or greater than 3 feet thick and less than 300 feet deep. Of the 73.2 billion short tons (BST), 19.3 BST were determined to be recoverable resources, of which approximately 2.1 BST were considered as recoverable resources by surface mining methods at a stripping ratio of 10:1 or less. (defined as recoverable resources for this assessment, based on economic modeling and regional mining analogs). Recoverable resources for underground mining methods (coal 8 to 15 feet thick and between 300 and 3,000 feet deep) totaled 17.2 BST. Out of the 19.3 BST assessed as recoverable coal resources, approximately 167 million short tons (MST) were considered to be reserves. Within the 7 coal zones, the Wasatch coal zone contains an original resource of about 6.8 BST billion short tons of coal, of which 2.6 BST are considered a recoverable resource and approximately 26.7 MST are considered reserves. The Overland coal zone, in the Fort Union Formation, contains an original resource of approximately 23 BST of coal, of which 8.4 BST are considered a recoverable resource and approximately 74 MST are considered reserves. The China Butte coal zone, in the Fort Union Formation, contains an original resource of 36.2 BST of coal, of which 6.3 BST are considered a recoverable resource and approximately 5.5 MST are considered reserves. The Almond coal zone, in the Almond Formation, contains an original resource of 7.0 BST, of which approximately 2.0 BST are considered a recoverable resource and 61 MST are considered reserves. Resources were not calculated for the coal zones within the Niland Tongue of the Wasatch Formation or the Cretaceous Lance and Allen Ridge Formations because the coal beds in those zones are relatively thin, discontinuous, and have a limited areal extent.

Wyoming↗
USGS2024

Minerals Yearbook, volume III, Area Reports — International — Africa and the Middle East

The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows: Volume I, Metals and Minerals, contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included. Volume II, Area Reports: Domestic, contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals. Volume III, Area Reports: International, is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section. The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcome.

Minerals Yearbook↗
USGS2024

Minerals Yearbook, volume III, Area Reports — International — Asia and the Pacific

The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows: Volume I, Metals and Minerals , contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included. Volume II, Area Reports: Domestic , contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals. Volume III, Area Reports: International , is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section. The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcomed.

Minerals Yearbook↗
USGS2024

Minerals Yearbook, volume III, Area Reports — International — Europe and central Eurasia

The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows: Volume I, Metals and Minerals , contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included. Volume II, Area Reports: Domestic , contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals. Volume III, Area Reports: International , is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section. The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcomed.

Minerals Yearbook↗
USGS2024

Minerals Yearbook, volume III, Area Reports — International — Latin America and Canada

The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows: Volume I, Metals and Minerals , contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included. Volume II, Area Reports: Domestic , contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals. Volume III, Area Reports: International , is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section. The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcomed.

Central America, South America↗
USGS2024

Minerals Yearbook, volume I, Metals and Minerals

The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows: Volume I, Metals and Minerals , contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included. Volume II, Area Reports: Domestic , contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals. Volume III, Area Reports: International , is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section. The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcome.

Minerals Yearbook↗
USGS2024

Minerals Yearbook, volume II, Area Reports — Domestic

The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows: Volume I, Metals and Minerals , contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included. Volume II, Area Reports: Domestic , contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals. Volume III, Area Reports: International , is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section. The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcome.

Minerals Yearbook↗
USGS2011

Nitrogen in Chinese coals

Three hundred and six coal samples were taken from main coal mines of twenty-six provinces, autonomous regions, and municipalities in China, according to the resource distribution and coal-forming periods as well as the coal ranks and coal yields. Nitrogen was determined by using the Kjeldahl method at U. S. Geological Survey (USGS), which exhibit a normal frequency distribution. The nitrogen contents of over 90% Chinese coal vary from 0.52% to 1.41% and the average nitrogen content is recommended to be 0.98%. Nitrogen in coal exists primarily in organic form. There is a slight positive relationship between nitrogen content and coal ranking. ?? 2011 Science Press, Institute of Geochemistry, CAS and Springer Berlin Heidelberg.

Chinese Journal of Geochemistry↗
USGS2013

Coal resources, reserves and peak coal production in the United States

In spite of its large endowment of coal resources, recent studies have indicated that United States coal production is destined to reach a maximum and begin an irreversible decline sometime during the middle of the current century. However, studies and assessments illustrating coal reserve data essential for making accurate forecasts of United States coal production have not been compiled on a national basis. As a result, there is a great deal of uncertainty in the accuracy of the production forecasts. A very large percentage of the coal mined in the United States comes from a few large-scale mines (mega-mines) in the Powder River Basin of Wyoming and Montana. Reported reserves at these mines do not account for future potential reserves or for future development of technology that may make coal classified currently as resources into reserves in the future. In order to maintain United States coal production at or near current levels for an extended period of time, existing mines will eventually have to increase their recoverable reserves and/or new large-scale mines will have to be opened elsewhere. Accordingly, in order to facilitate energy planning for the United States, this paper suggests that probabilistic assessments of the remaining coal reserves in the country would improve long range forecasts of coal production. As it is in United States coal assessment projects currently being conducted, a major priority of probabilistic assessments would be to identify the numbers and sizes of remaining large blocks of coal capable of supporting large-scale mining operations for extended periods of time and to conduct economic evaluations of those resources.

International Journal of Coal Geology↗
USGS1874

Progress report upon geographical and geological explorations and surveys west of the one hundredth meridian, in 1872, under the direction of Brigadier General A.A. Humphreys, Chief of Engineers, United States Army

It is proposed to present in this progress report- 1st. A short chapter devoted to the analyzation of the results under their separate and systematic heads. 2d. A chapter upon the special subjects of mining, agriculture, irrigation, routes of communication, Indians, &c., to conclude with a project for the surveys contemplated for the ensuing season; the whole to be accompanied by appendixes, containing reports of certain officers and civilian assistants, and a, map upon which are delineated the areas of territory west of the one hundredth meridian yet unsurveyed instrumentally, and the relation to them of lines and areas traversed and mapped by exploration and survey parties under the auspices of the War Department, so far as the exhibit can be prepared at the office of the survey.

Report↗
USGS1938

Fifty-ninth annual report of the Director of the Geological Survey

Basically important in the general program of conservation and development were the results of the Geological Survey's work during the fiscal year 1938. Investigations of the Nation's mineral and water supplies were conducted with all possible vigor and dispatch, thousands of square miles were surveyed for topographic maps, and technical supervision was given to prospecting, mining, and producing operations on public and Indian lands. This work was accomplished through the use of the regularly appropriated funds, the co-operative funds from States, counties, and municipalities, the funds transferred from other departments of the Government for types of work within the Survey's field, and the emergency funds derived chiefly from the Public Works Administration and devoted largely to mapping of various types and to studies of floods. The aggregate expenditures amounted to $5,248,000, which was 265,000 less than the amount expended during the preceding year.

Annual Report↗