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USGS1973

United States mineral resources

The work on this volume began in January 1972, but in a broader sense its production began many years ago. The chapters were written by geologists most of whom have had many years of experience studying the geology of mineral deposits, and more particularly the commodities about which they have written here. A total of nearly 2,300 man-years of professional experience in the geology of mineral resources is represented by the authors of the volume, and about 30 man-years went directly into its preparation. Each chapter contains not only a synthesis of the state of knowledge of the geology of the commodity, but also an appraisal of the known resources, and an examination of the geologic possibilities for finding additional deposits. In January 1972, responsibility for the preparation of the volume was assigned to us as co-editors, and we were given a tentative list of commodities and authors. We provided each author with a suggested outline of general topics to be covered, and some guidelines as to scope and philosophy of approach, but beyond that we avoided any attempt to fit each chapter into a stereotype. Moreover, the types of commodities range from the major metals and industrial minerals such as copper, silver, and fluorspar, which have been the subject of geologic research for years, to other commodities that are of such varied geologic nature (such as pigments or gemstones) or of such minor present importance (such as scandium or thallium) that they cannot be treated from the same viewpoint as the major minerals. The chapters range, therefore, from comprehensive summary reports to general essays that reflect the individuality of the authors as well as the variation among commodities. Throughout the book the emphasis is on geology, but each chapter contains some summary information on uses, technology, and economics. These summaries are not meant to be exhaustive, however, and additional details are in the 1970 edition of "Mineral Facts and Problems" (Bulletin 650 of the U.S. Bureau of Mines) ; indeed, we regard that book and the present volume as being complementary. In the examination of the geologic possibilities for finding new deposits-in many respects the principal innovative contributions of this volume-we asked the authors to frankly apply the limits of their ingenuity and not only to summarize current theories but also to express their own intuitive ideas, however speculative and unconventional they may seem, that have come from years of study devoted to the origin of mineral deposits. Readers will see that some authors have speculated more courageously than others. In any case, we believe readers will find all the chapters interesting, and many stimulating; and a few we believe can be frankly characterized as intellectually exciting. Most chapters include a section on prospecting techniques, and a summary of geologic or related problems on which the authors believe research might be most fruitful in the continuing efforts to find new resources. An integral part of the book is the bibliographic material cited at the conclusion of each chapter, in lieu of repetition of detailed descriptions already in print. Index and "spot" maps are not included in most chapters because they are available elsewhere, and in many cases with more detail than could possibly be included here. Maps showing the distribution of known deposits of many commodities in the United States are available in the Mineral Resource (MR) map series of the U.S. Geological Survey and in the National Atlas of the United States. The first three chapters deal not with resources of specific commodities but with general information that is pertinent to the study of mineral resources. In the introductory chapter we discuss the purposes of the book, the distinctions between reserves and various categories of resources, and some general conclusions drawn from our view of the book in its entirety. In the second chapter V. E. McKelvey discusses the problems of mineral-resource estimates and public policy. In the third chapter, R. L. Erickson discusses some new points of view on the relation of reserves and resources to the crustal abundance of elements. We acknowledge with thanks the cooperation of our colleagues in all phases of the preparation of this volume. Whatever success the book may attain is due entirely to a total effort. A paragraph of acknowledgment originally submitted as a part of the chapter on "Nuclear fuels" is given here instead because we feel it applied to all chapters: "The writers have drawn freely from published information, not all of which is cited, and from their colleagues, none of whom are given specific credit. The reader should be aware that the paper could not have been written without these sources." We extend specific thanks to Michael Fleischer for preparation of summaries of geochemical information that are included in many chapters.

Professional Paper↗

USGS1977

Entropy, materials, and posterity

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

Geologische Rundschau↗

USGS1905

Report on progress of investigations of mineral resources of Alaska in 1904

During the last two years the United States Geological Survey has met the demand of the mining public for early publication of economic results by issuing an annual bulletin entitled "Contributions to Economic Geology." Though these volumes have made no attempt to treat exhaustively any of the subject discussed, and while many of the included papers have been but the barest outlines, they have met a cordial reception from those interested in developing the mineral resources of the country. Among the many papers in these bulletins were a number devoted to the mineral deposits of Alaska. In view of the rapid extension of the Alaskan work of the Geological Survey and its segregation in a distinct division, it has seemed desirable to issue a separate publication containing the papers summarizing the previous year's work.

Alaska↗

USGS2000

Regional Crustal Structures and Their Relationship to the Distribution of Ore Deposits in the Western United States, Based on Magnetic and Gravity Data

Upgraded gravity and magnetic databases and associated filtered-anomaly maps of western United States define regional crustal fractures or faults that may have guided the emplacement of plutonic rocks and large metallic ore deposits. Fractures, igneous intrusions, and hydrothermal circulation tend to be localized along boundaries of crustal blocks, with geophysical expressions that are enhanced here by wavelength filtering. In particular, we explore the utility of regional gravity and magnetic data to aid in understanding the distribution of large Mesozoic and Cenozoic ore deposits, primarily epithermal and porphyry precious and base metal deposits and sediment-hosted gold deposits in the western United States cordillera. On the broadest scale, most ore deposits lie within areas characterized by low magnetic properties. The Mesozoic Mother Lodge gold belt displays characteristic geophysical signatures (regional gravity high, regional low-to-moderate background magnetic field anomaly, and long curvilinear magnetic highs) that might serve as an exploration guide. Geophysical lineaments characterize the Idaho-Montana porphyry belt and the La Caridad-Mineral Park belt (from northern Mexico to western Arizona) and thus indicate a deep-seated control for these mineral belts. Large metal accumulations represented by the giant Bingham porphyry copper and the Butte polymetallic vein and porphyry copper systems lie at intersections of several geophysical lineaments. At a more local scale, geophysical data define deep-rooted faults and magmatic zones that correspond to patterns of epithermal precious metal deposits in western and northern Nevada. Of particular interest is an interpreted dense crustal block with a shape that resembles the elliptical deposit pattern partly formed by the Carlin trend and the Battle Mountain-Eureka mineral belt. We support previous studies, which on a local scale, conclude that structural elements work together to localize mineral deposits within regional zones or belts. This study of mineral deposits of the western United States demonstrates the ability of magnetic and gravity data to elucidate the regional geologic framework or structural setting and to contribute in locating favorable environments for hydrothermal mineralization.

Economic Geology↗

USGS1961

Distribution of uranium ore deposits in the elk ridge area, San Juan County, Utah

The Elk Ridge area of southeastern Utah contains uranium ore deposits in two lower members of the Chinle formation of Late Triassic age. Each member is mineralized in different parts of the area , and where both are present only the lower contains ore . Across the Elk Ridge area from southwest to northeast, successively younger beds lap onto the unconformity that separates the Chinle from the underlying Moenkopi formation of Triassic(?), Early and Middle(?) Triassic age. Important uranium deposits have been found only in sandstone beds of the Chinle that are in contact with the Moenkopi. Sandstone of the Chinle formation lies on the Moenkopi (or is separated from it by gray mudstone of the Chinle no thicker than the depths of most of the known paleostream channel scours) in two separate parts of the Elk Ridge area . These "favorable areas" contain all the mines and important prospects. The ore deposits are flat-lying tabular to lenticular bodies in fluvial sandstone beds of the Chinle with fine-grained black uranium minerals chiefly interstitial to sand grains and as replacement of carbonaceous material. Most of the ore -bearing sandstone beds are discontinuous lenses intertonguing with and overlain by relatively impermeable mudstone. Contact of the host sandstone with the underlying Moenkopi seems to be a prerequisite for ore as the ore bodies are generally within a few feet of such contact areas and sandstone lenses separated from the Moenkopi by gray mudstone are generally not ore bearing. The consistent association of ore deposits with the Chinle-Moenkopi contact suggests that mineralizing solutions were introduced into the host beds from their areas of contact with the Moenkopi formation. Impermeable barriers overlying ore -bearing parts of the host sandstones were probably an important control on the deposition of ore minerals from solution. Hypofiltration of metallic constituents from ascending ore solutions may have been important. It is also possible that the overlying barriers formed traps for H2S gas or fluid hydrocarbons and thus localized a reducing chemical environment in which ore minerals were later precipitated.

Utah↗

USGS1955

Geochemical exploration for antimony in southeastern Alaska

Preliminary geochemical prospecting by the Geological Survey was carried out in 1952 in muskeg-covered ground at Caamano Point, Cleveland Peninsula, Alaska, in an effort to delimit areas of stibnite concentrations. It was conducted to aid, if possible, a prospecting project of the Defense Minerals Exploration. Samples were collected from soil and decomposed limestone-and-schist bedrock at depths ranging from 18 inches to 60 inches, by means of a pipe with an interior plunger. Initial sampling was followed by detailed sampling of the areas where the antimony content of the soils consistently averaged more than 300 ppm. These Areas of major soil concentrations were prospected by surface trenching and percussion drilling to depths of 20 feet which proved the existence of stibnite ore. Next a shaft and drifts made in the most favorable area proved disseminated stibnite ore to depths of 60 feet. This geochemical work of soil sampling to indicate hidden ore bodies in a typical Alaskan muskeg area is believed to be the first application in Alaska of such techniques in active ore exploration. The results show the economic feasibility of such exploration as a first step in extending the known boundaries of mineralized areas, and in directing initial exploration toward the most favorable areas of near-surface ore bodies. Data are presented to help establish values of soil content of antimony that may be considered as normal in this type of geologic terrain.

Alaska↗

USGS1995

Economics and the 1995 National Assessment of U.S. oil and gas resources

This report summarizes the economic component of the U.S. Geological Survey's 1995 National Assessment of oil and gas resources for the US onshore areas and State waters. This area accounts for 80 percent of US hydrocarbon production and 85 percent of US proved reserves. The Minerals Management Service has released a parallel study for Federal offshore areas (1996). Estimates are as of January 1994. The economic evaluation uses mean values of the technically recoverable resources assessed by geologists.

Open-File Report↗

USGS1998

Geological setting and petrogenesis of symmetrically zoned, miarolitic granitic pegmatites at Stak Nala, Nanga Parbat - Haramosh Massif, northern Pakistan

Miarolitic granitic pegmatites in the Stak valley in the northeast part of the Nanga Parbat - Haramosh Massif, in northern Pakistan, locally contain economic quantities of bi- and tricolored tourmaline. The pegmatites form flat-lying sills that range from less than 1 m to more than 3 m thick and show symmetrical internal zonation. A narrow outer or border zone of medium-to coarse-grained oligoclase - K-feldspar - quartz grades inward to a very coarse-grained wall zone characterized by K-feldspar - oligoclase - quartz - schorl tourmaline. Radiating sprays of schorl and flaring megacrysts of K-feldspar (intermediate microcline) point inward, indicating progressive crystallization toward the core. The core zone consists of variable mixtures of blocky K-feldspar (intermediate microcline), oligoclase, quartz, and sparse schorl or elbaite, with local bodies of sodic aplite and miarolitic cavities or "pockets". Minor spessartine-almandine garnet and lo??llingite are disseminated throughout the pegmatite, but were not observed in the pockets. The pockets contain well-formed crystals of albite, quartz, K-feldspar (maximum microcline ?? orthoclase overgrowths), schorl-elbaite tourmaline, muscovite or lepidolite, topaz, and small amounts of other minerals. Elbaite is color-zoned from core to rim: green (Fe2+- and Mn2+-bearing), colorless (Mn2+-bearing), and light pink (trace Mn3+). Within ???10 cm of the pegmatites, the granitic gneiss wallrock is bleached owing to conversion of biotite to muscovite, with local quartz and albite added. Schorl is disseminated through the altered gneiss, and veins of schorl with bleached selvages locally traverse the wallrock up to 1 m from the pegmatite contact. The schorl veins can be traced into the outer part of the wall zone, which suggests that they formed from aqueous fluids derived during early saturation of the pegmatite-forming leucogranitic magma rich in H2O, F, B, and Li. Progressive crystallization resulted in a late-stage sodic magma and abundant aqueous fluids. Two late stages of volatile escape are recognized: the first stage caused pressure-quenching of the last magma, which produced aplite and caused albitization (An3 to An8) of earlier crystallized K-feldspar and oligoclase. The second stage, released during the rupture of miarolitic cavities, produced platy albite ("cleavelandite," An1) locally associated with F-rich moscovite and elbaite. Albitization is likely due to cooling of alkali-fluoride-dominated fluids at less than 2 kbar pressure. The pegmatites are derived from Himalayan leucogranitic magma emplaced prior to 5 Ma into granulitic gneiss that was at 300?? to 550??C and 1.5 to 2 kbar. The pegmatites were emplaced during uplift of the Haramosh Massif, since they cross-cut ductile normal faults but are cut by brittle normal faults. Economically important pink tourmaline mineralization formed in pockets concentrated near the crest of a broad antiform, as a result of trapping of late magmatic aqueous fluids that had become Fe-poor owing to the prior crystallization of schorl.

Canadian Mineralogist↗

USGS2010

Western Mineral and Environmental Resources Science Center--providing comprehensive earth science for complex societal issues

Minerals in the environment and products manufactured from mineral materials are all around us and we use and come into contact with them every day. They impact our way of life and the health of all that lives. Minerals are critical to the Nation's economy and knowing where future mineral resources will come from is important for sustaining the Nation's economy and national security. The U.S. Geological Survey (USGS) Mineral Resources Program (MRP) provides scientific information for objective resource assessments and unbiased research results on mineral resource potential, production and consumption statistics, as well as environmental consequences of mining. The MRP conducts this research to provide information needed for land planners and decisionmakers about where mineral commodities are known and suspected in the earth's crust and about the environmental consequences of extracting those commodities. As part of the MRP scientists of the Western Mineral and Environmental Resources Science Center (WMERSC or 'Center' herein) coordinate the development of national, geologic, geochemical, geophysical, and mineral-resource databases and the migration of existing databases to standard models and formats that are available to both internal and external users. The unique expertise developed by Center scientists over many decades in response to mineral-resource-related issues is now in great demand to support applications such as public health research and remediation of environmental hazards that result from mining and mining-related activities. Western Mineral and Environmental Resources Science Center Results of WMERSC research provide timely and unbiased analyses of minerals and inorganic materials to (1) improve stewardship of public lands and resources; (2) support national and international economic and security policies; (3) sustain prosperity and improve our quality of life; and (4) protect and improve public health, safety, and environmental quality. The MRP supports approximately 40 USGS research specialists who utilize cooperative agreements with universities, industry, and other governmental agencies to support their collaborative research and information exchange. Scientists of the WMERSC study how and where non-fuel mineral resources form and are concentrated in the earth's crust, where mineral resources might be found in the future, and how mineral materials interact with the environment to affect human and ecosystem health. Natural systems (ecosystems) are complex - our understanding of how ecosystems operate requires collecting and synthesizing large amounts of geologic, geochemical, biologic, hydrologic, and meteorological information. Scientists in the Center strive to understand the interplay of various processes and how they affect the structure, composition, and health of ecosystems. Such understanding, which is then summarized in publicly available reports, is used to address and solve a wide variety of issues that are important to society and the economy. WMERSC scientists have extensive national and international experience in these scientific specialties and capabilities - they have collaborated with many Federal, State, and local agencies; with various private sector organizations; as well as with foreign countries and organizations. Nearly every scientific and societal challenge requires a different combination of scientific skills and capabilities. With their breadth of scientific specialties and capabilities, the scientists of the WMERSC can provide scientifically sound approaches to a wide range of societal challenges and issues. The following sections describe examples of important issues that have been addressed by scientists in the Center, the methods employed, and the relevant conclusions. New directions are inevitable as societal needs change over time. Scientists of the WMERSC have a diverse set of skills and capabilities and are proficient in the collection and integration of

Circular↗

USGS2017

Geologic map of the Dusar area, Herat Province, Afghanistan; Modified from the 1973 original map compilations of V.I. Tarasenko and others

The geologic maps and cross sections presented in this report are redrafted and modified versions of the Geologic map and map of useful minerals of the Dusar area (scale 1:50,000) and Geologic sketch map of the Dusar and Namak-sory ore occurrences (scale 1:10,000), located in the Herat Province, Afghanistan. The original maps and cross sections are contained in unpublished Soviet report no. 0290 (Tarasenko and others, 1973) prepared in cooperation with the Ministry of Mines and Industries of the Royal Government of Afghanistan, in Kabul during 1973 under contract no. 50728. The redrafted maps and cross sections (modified from Tarasenko and others, 1973) illustrate the geological structure and mineral occurrences of the Dusar copper-gold-silver-lead-zinc prospect area of western Afghanistan, located within the Dusar-Shaida copper and tin area of interest (AOI), Herat Province, Afghanistan. Mineralization in the Dusar area is hosted within Early Jurassic to Early Cretaceous stratified volcanic and sedimentary rocks associated with numerous diabase and gabbro-diabase intrusive bodies and is generally near a major northeast-trending system of faults and quartz veins. Host rocks consist of quartz keratophyre and quartz-feldspar porphyry, with layers of schist, phyllite, and quartz-chlorite and chlorite-sericite slate; and limestone and shale, with schist and carbonate-chlorite and chlorite slate. Known mineralization includes an extensive quartz vein system, shown on the map as the “northern occurrence,” as well as the Dusar and Namak-sory gossan zones, interpreted to have formed from remnant pyrite mineralization. The veins of the northern occurrence and their altered host rocks are known to contain anomalous to economic concentrations of precious and base metals, with concentrations locally in excess of 2 parts per million gold, 100 parts per million silver, 5 percent copper, and 1 percent lead. These veins occur in swarms, and are hosted along structures that are approximately concordant with the plane of the metamorphic fabric. The veins consist mostly of quartz, with minor carbonate and sulfide minerals, and display weak alteration halos along their margins. The gossans are locally anomalous in these metals, but their size and extent makes them attractive exploration targets for potential massive sulfide mineralization. The Dusar gossan zone is a massive, ochreous, and siliceous limonitic rock, approximately 2,200 meters long, 30 to 250 meters wide, and 2.0 to 7.2 meters thick. Drilling below the Dusar gossan intersected a siliceous, sericitic, and limonitic rock underlain by quartz keratophyre with abundant disseminated pyrite. Mineralized sections grade 0.06 weight percent copper and up to 0.05 weight percent zinc. The Namak-sory gossan zone contains a similar deposit with anomalous concentrations of copper, zinc, and gold. The redrafted maps and cross sections reproduce the topology of rock units, contacts, and faults of the original Soviet maps and cross sections, and include minor modifications based on examination of the originals and observations made during two brief field visits by USGS staff in August, 2010, and June, 2013.

Dusar Area, Herat Province↗

USGS1966

Dawsonite in the green river formation of Colorado

Dawsonite NaAl(OH)2C03 is a rare mineral that occurs in relative abundance over hundreds of square miles in the Piceance Creek Basin of northwestern Colorado, as a rock-forming constituent of the oil shales in the green River Formation. In some specimens it makes up 25 percent by weight of the shale. Containing 35 percent of acid-soluble A1203, it has been viewed as a potential ore of aluminum. The dawsonite extends through 700 feet of continuous section of high-grade oil shale (averaging 25 gallons per ton), which may be as much as 1,500 feet in thickness. Its distribution, areally and stratigraphically, is reviewed; methods for its identification, and for its quantitative determination in the oil shale, with special reference to X-ray diffraction procedures are described; and the geochemistry of dawsonite, as it relates to the origin of the mineral, is considered. The scattered literature on dawsonite is briefly summarized. © 1966 Society of Economic Geologists, Inc..

Colorado↗

USGS1916

Contributions to economic geology (short papers and preliminary reports), 1915: Part I. - metals and nonmetals except fuels

This volume is the thirteenth of a series that includes Bulletins 213, 225, 260, 285, 315, 340, 380, 430, 470, 530, 540, and 580, "Contributions to economic geology" for 1902, 1903, 1904, 1905, 1906 (Pt. I), 1907 (Pt. I), 1908 (Pt. I), 1909 (Pt. I), 1910 (P t. I), 1911 (Pt. I) , 1912 (Pt. I), and 1913 (Pt. I), respectively . These bulletins are prepared primarily to insure prompt publication of the economic results of investigations made by the United States Geological Survey. Beginning with the present volume the year included in the title will be the year of publication 1 instead of the year in which the field work reported was done. This volume is therefore dated 1915, and there will be no volume entitled "Contributions to economic geology, 1914." As the subtitle indicates, the papers included are of two classes -(1) short papers giving comparatively detailed description of occurrences that have economic interest but are not of sufficient importance to warrant a more extended description; (2) preliminary reports on economic investigations the results of which are to be published later in more detailed form. These papers are such only as have a direct economic bearing, all topic of purely scientific interest being excluded. Each paper has been issued as an advance chapter as soon as it was ready. Brief abstracts of the publications of the year are given in the annual report of the Director. The complete list of Survey publications affords, by means of finding list of subjects and of authors, further aid in ascertaining the extent of the Survey's work in economic geology. Since 1905 the annual economic bulletin has been printed in two parts, the second part comprising paper on mineral fuels. These volumes for 1906, 1907, 190 , 1909, 1910, 1911, 1912, and 1913 are Bulletins 316, 341, 381, 431, 471, 531, 541, and 581. Bulletin 621 forms Part II of the "Contributions" for 1915. The reports on work in Alaska have been printed in a separate series since 1904, the volume so far issued being Bulletins 259, 284, 314, 345, 379, 442, 480, 520, 542, 592, and 622.

Bulletin↗

USGS1984

Phosphate rock resources of the United States

In 1980, the United States produced about 54 million tons of phosphate rock, or about 40 percent of the world's production, of which a substantial amount was exported, both as phosphate rock and as chemical fertilizer. During the last decade, predictions have been made that easily ruinable, low-cost reserves of phosphate rock would be exhausted, and that by the end of this century, instead of being a major exporter of phosphate rock, the United States might become a net importer. Most analysts today, however, think that exports will indeed decline in the next one or two decades, but that resources of phosphate are sufficient to supply domestic needs for a long time into the future. What will happen in the future depends on the actual availability of low-cost phosphate rock reserves in the United States and in the world. A realistic understanding of future phosphate rock reserves is dependent on an accurate assessment, now, of national phosphate rock resources. Many different estimates of resources exist; none of them alike. The detailed analysis of past resource estimates presented in this report indicates that the estimates differ more in what is being estimated than in how much is thought to exist. The phosphate rock resource classification used herein is based on the two fundamental aspects of a mineral resource(l) the degree of certainty of existence and (2) the feasibility of economic recovery. The comparison of past estimates (including all available company data), combined with the writers' personal knowledge, indicates that 17 billion metric tons of identified, recoverable phosphate rock exist in the United States, of which about 7 billion metric tons are thought to be economic or marginally economic. The remaining 10 billion metric tons, mostly in the Northwestern phosphate district of Idaho, are considered to be subeconomic, ruinable when some increase in the price of phosphate occurs. More than 16 billion metric tons probably exist in the southeastern Coastal Plain phosphate province, principally in Florida and North Carolina and offshore in the shallow Atlantic Ocean from North Carolina to southern Florida. This resource is considered to be hypothetical because it is based on geologic inference combined with sparse drilling data. Total resources of phosphate rock in the United States are sufficient to supply domestic demands for the foreseeable future, provided that drilling is done to confirm hypothetical resources and the chemistry of the deposits is determined. Mining and beneficiation techniques will have to be modified or improved, and new techniques will have to be developed so that these deposits can be profitably exploited.

Circular↗

USGS2006

Calibrated Landsat ETM+ nonthermal-band image mosaics of Afghanistan

In 2005, the U.S. Agency for International Development and the U.S. Trade and Development Agency contracted with the U.S. Geological Survey to perform assessments of the natural resources within Afghanistan. The assessments concentrate on the resources that are related to the economic development of that country. Therefore, assessments were initiated in oil and gas, coal, mineral resources, water resources, and earthquake hazards. All of these assessments require geologic, structural, and topographic information throughout the country at a finer scale and better accuracy than that provided by the existing maps, which were published in the 1970s by the Russians and Germans. The very rugged terrain in Afghanistan, the large scale of these assessments, and the terrorist threat in Afghanistan indicated that the best approach to provide the preliminary assessments was to use remotely sensed, satellite image data, although this may also apply to subsequent phases of the assessments. Therefore, the first step in the assessment process was to produce satellite image mosaics of Afghanistan that would be useful for these assessments. This report discusses the production and characteristics of the fundamental satellite image databases produced for these assessments, which are calibrated image mosaics of all six Landsat nonthermal (reflected) bands.

Open-File Report↗

USGS2007

Landsat ETM+ False-Color Image Mosaics of Afghanistan

In 2005, the U.S. Agency for International Development and the U.S. Trade and Development Agency contracted with the U.S. Geological Survey to perform assessments of the natural resources within Afghanistan. The assessments concentrate on the resources that are related to the economic development of that country. Therefore, assessments were initiated in oil and gas, coal, mineral resources, water resources, and earthquake hazards. All of these assessments require geologic, structural, and topographic information throughout the country at a finer scale and better accuracy than that provided by the existing maps, which were published in the 1970's by the Russians and Germans. The very rugged terrain in Afghanistan, the large scale of these assessments, and the terrorist threat in Afghanistan indicated that the best approach to provide the preliminary assessments was to use remotely sensed, satellite image data, although this may also apply to subsequent phases of the assessments. Therefore, the first step in the assessment process was to produce satellite image mosaics of Afghanistan that would be useful for these assessments. This report discusses the production of the Landsat false-color image database produced for these assessments, which was produced from the calibrated Landsat ETM+ image mosaics described by Davis (2006).

Open-File Report↗

USGS1977

National coal resource investigations of the United States Geological Survey

The objective of this report is to provide a record of some of the goals and accomplishments of the coal resource investigations of the U. S. Geological Survey for 1977. Successful completion of these goals will aid the Nation in the years ahead because proper usage of coal resource data may lessen economic displacements resulting from the energy shortage. This report is concerned only with one mineral fuel -- coal -- and only with coal resource investigations in the Geologic Division of the U. S. Geological Survey. Other divisions involved with coal or coal-related work are the Conservation, Water Resources, and Topographic Divisions. It is one of a series of reports on the energy resource studies conducted by the Geological Survey that provide a public record of the objectives, activities, and accomplishments of these programs. Similar reports have been prepared on oil and gas, oil shale, uranium, thorium, and energy-related industrial minerals. This report includes descriptions of the program, each sub-element of the program, individual projects, and a selected list of program publications from 1970-76. It also describes how the program is responsive to Presidential pronouncements and Congressional mandates. The program is cooperative with several Federal bureaus, many state agencies, universities, and industry. This coordination assures that the program supplements the work of these interested groups and is not duplicative. A scientific program such as the coal resource investigations is difficult for the non-involved person to understand solely from the existing reports on various studies made in the program. This report provides an explanation that the scientist, decision maker, personnel of other government agencies, and the layman can use to relate various activities and to gain a better understanding of the relation of coal to the Nation's requirements for energy and of the importance of a carefully planned program on this energy resource.

Open-File Report↗

USGS1929

Geology and ground-water resources of North Dakota, with a discussion of the chemical character of the water

Water is the most valuable of the mineral resources. The study of ground waters is therefore clearly within the field of economic geology and constitutes an important part of the work of the geological surveys, both State and national, as defined by law. In the spring of 1911 the investigation of the ground waters of North Dakota was begun by the North Dakota Geological Survey, and the work was assigned to the author of this paper. During each of the three summers 1911, 1912, and 1913 several weeks were devoted by the author to the field work of a general survey. A report on the ground waters of the State was then prepared by him and was transmitted by the director of the North Dakota Geological Survey to the State printing commission for publication. However, owing to lack of available funds the report was not published. A portion of the summer of 1914 was given to a study of artesian conditions in the Souris River Basin. Since that time considerable work has been done in connection with detailed surveys made for a number of cities and villages in an effort to obtain the best available supply of water for public use. During the summer of 1920 arrangements were made by the United States Geological Survey with the North Dakota Geological Survey whereby the author completed the work as fully as possible by correspondence and brought the report up to date. In the spring of 1921 samples of water from 196 sources were collected by the author and J. H. Buchanan and were sent to the United States Geological Survey for analysis. Most of these samples were analyzed by H. B. Riffenburg, who has used the analyses for a description of the chemical character of ground waters in the State. In addition to the analyses of samples collected in connection with the preparation of this report, over 700 partial analyses from different sources were examined. These analyses are not given in this paper, because the location of many of the wells was not stated definitely, and most of the analyses were incomplete. They were useful, however, in confirming the conclusions based on the analyses that are printed, particularly for counties where only a few samples were collected for this report.

North Dakota↗

USGS2003

Geomedia: Mapping Colorado at a fine scale

Currently, only 24 percent of Colorado's spectacular geology has been mapped at the fine scale of 1:24,000. At the same time, the state hosts many geologic hazards. Most maps of Colorado are at much broader scales, failing to show detail of basic geology crucial to safe engineering and building practices in a state that had the third-fastest-growing population during the 1990s. And the 2000 Census showed that the state, despite some economic woes, remains one of the fastest growing. Detailed geologic maps also aid the mineral industries that help fuel such growth. Since 1992, the Colorado Geological Survey (CGS) has mapped 1:24,000-scale quadrangles in high-impact areas under the STATEMAP component of the National Cooperative Geologic Mapping Program. In 2002, CGS completed its 43rd geologic quadrangle map. The long-range plan for the state is to complete 116 high-priority quadrangles in the next 15 years. The survey's approach is to select rapidly growing areas with relatively high potential for hazards and map contiguous quadrangles. In addition to mapping bedrock, CGS geologists have mapped the Quaternary deposits at the surface. Understanding these deposits is extremely important for implementing sound engineering practices because of potential for subsidence and landslides. The CGS mapping has not only yielded information about potential hazards, but also advanced scientific understanding of the state.

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