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USGS2013

U.S. Geological Survey environmental health science strategy — Providing environmental health science for a changing world

Executive Summary America has an abundance of natural resources. We have bountiful clean water, fertile soil, and unrivaled national parks, wildlife refuges, and public lands. These resources enrich our lives and preserve our health and wellbeing. These resources have been maintained because of our history of respect for their value and an enduring commitment to their vigilant protection. Awareness of the social, economic, and personal value of the health of our environment is increasing. The emergence of environmentally driven diseases caused by exposure to contaminants and pathogens is a growing concern worldwide. New health threats and patterns of established threats are affected by both natural and anthropogenic changes to the environment. Human activities are key drivers of emerging (new and re-emerging) health threats. Societal demands for land and natural resources, quality of life, and economic prosperity lead to environmental change. Natural earth processes, climate trends, and related climatic events will compound the environmental impact of human activities. These environmental drivers will influence exposure to disease agents, including viral, bacterial, prion, and fungal pathogens, parasites, synthetic chemicals and substances, natural earth materials, toxins, and other biogenic compounds. The U.S. Geological Survey (USGS) defines environmental health science broadly as the interdisciplinary study of relations among the quality of the physical environment, the health of the living environment, and human health. The interactions among these three spheres are driven by human activities, ecological processes, and natural earth processes; the interactions affect exposure to contaminants and pathogens and the severity of environmentally driven diseases in animals and people. This definition provides USGS with a framework for synthesizing natural science information from across the Bureau and providing it to environmental, natural resource, agricultural, and public health managers. USGS specializes in science at the environment-health interface, by characterizing the processes that affect the interaction among the physical environment, the living environment, and people, and the resulting factors that affect ecological and human exposure to disease agents. The USGS is a Federal science agency with a broad range of natural science expertise relevant to environmental health. USGS provides scientific information and tools as a scientific basis for management and policy decisionmaking. This report describes a 10-year strategy that encompasses the portfolio of USGS environmental health science. It summarizes national environmental health priorities that USGS is best suited to address, and will serve as a strategic framework for USGS environmental health science goals, actions, and outcomes for the next decade. Implementation of this strategy is intended to aid coordination of USGS environmental health activities and to provide a focal point for disseminating information to stakeholders. The “One Health” paradigm advocated by the World Health Organization (WHO; World Health Organization, 2011), and the American Veterinary Medical Association (AVMA; American Veterinary Medical Association, 2008), among others, is based on a general recognition that the health of humans, animals, and the environment are inextricably linked. Thus, successful efforts to protect that health will require increased interdisciplinary research and increased communication and collaboration among the broader scientific and health community. This strategy is built upon that paradigm.

Circular↗
USGS1982

Geophysical logs of four drill holes, Acord Lakes and Emery West quadrangles, Sevier County, Utah

This report presents the geophysical logs for four drill holes drilled during 1981 in the Skumpah Creek area (Acord Lakes quadrangle) and The Pines area (Emery West quadrangle), Sevier County, Utah. Figures 1 and 2 show drill-hole locations, and figures 3-7 are the geophysical logs. The drilling was done by a private drilling company under contract to the U.S. Geological Survey. The sites of all the drill holes are within the Wasatch Plateau Known Recoverable Coal Resource Area (KRCRA). Three of the sites are in the Richfield Ranger District of the Fishlake National Forest and one site is in the Ferron Ranger District of the Manti-LaSal National Forest. The purpose of the drilling was to identify and evaluate coal resources under public lands that may be included in a future coal leasing program. The area is underlain by Cretaceous and younger rocks (table 1). The coal seams of economic interest are in the lower 200 ft of the Upper Cretaceous Blackhawk Formation, a complex sequence of intertonguing sandstone, shale, and coal. Regional dip of the strata in the area is approximately 2° to the northwest. The geology and coal resources of the area were described by Spieker (1931), Doelling (1972), and Smith (1981). The drill holes were rotary drilled and the thicknesses and depths were determined from geophysical logs. In order to obtain data on the quality of the coal, the coal-bearing section in one hole was core drilled. Table 2 gives the drilling and logging information for the four completed holes. All drill holes were bottomed in the Upper Cretaceous Star Point Sandstone.

Utah↗
USGS2017

Genetic and grade and tonnage models for sandstone-hosted roll-type uranium deposits, Texas Coastal Plain, USA

The coincidence of a number of geologic and climatic factors combined to create conditions favorable for the development of mineable concentrations of uranium hosted by Eocene through Pliocene sandstones in the Texas Coastal Plain. Here 254 uranium occurrences, including 169 deposits, 73 prospects, 6 showings and 4 anomalies, have been identified. About 80 million pounds of U 3 O 8 have been produced and about 60 million pounds of identified producible U 3 O 8 remain in place. The development of economic roll-type uranium deposits requires a source, large-scale transport of uranium in groundwater, and deposition in reducing zones within a sedimentary sequence. The weight of the evidence supports a source from thick sequences of volcanic ash and volcaniclastic sediment derived mostly from the Trans-Pecos volcanic field and Sierra Madre Occidental that lie west of the region. The thickest accumulations of source material were deposited and preserved south and west of the San Marcos arch in the Catahoula Formation. By the early Oligocene, a formerly uniformly subtropical climate along the Gulf Coast transitioned to a zoned climate in which the southwestern portion of Texas Coastal Plain was dry, and the eastern portion humid. The more arid climate in the southwestern area supported weathering of volcanic ash source rocks during pedogenesis and early diagenesis, concentration of uranium in groundwater and movement through host sediments. During the middle Tertiary Era, abundant clastic sediments were deposited in thick sequences by bed-load dominated fluvial systems in long-lived channel complexes that provided transmissive conduits favoring transport of uranium-rich groundwater. Groundwater transported uranium through permeable sandstones that were hydrologically connected with source rocks, commonly across formation boundaries driven by isostatic loading and eustatic sea level changes. Uranium roll fronts formed as a result of the interaction of uranium-rich groundwater with either (1) organic-rich debris adjacent to large long-lived fluvial channels and barrier–bar sequences or (2) extrinsic reductants entrained in formation water or discrete gas that migrated into host units via faults and along the flanks of salt domes and shale diapirs. The southwestern portion of the region, the Rio Grande embayment, contains all the necessary factors required for roll-type uranium deposits. However, the eastern portion of the region, the Houston embayment, is challenged by a humid environment and a lack of source rock and transmissive units, which may combine to preclude the deposition of economic deposits. A grade and tonnage model for the Texas Coastal Plain shows that the Texas deposits represent a lower tonnage subset of roll-type deposits that occur around the world, and required aggregation of production centers into deposits based on geologic interpretation for the purpose of conducting a quantitative mineral resource assessment.

Texas↗
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↗
USGS2020

Characterization of the unconventional Tuscaloosa marine shale reservoir in southwestern Mississippi, USA: Insights from optical and SEM petrography

This study presents new optical petrography and electron microscopy data, interpreted in the context of previously published petrophysical, geochemical, and mineralogical data, to further characterize the Tuscaloosa marine shale (TMS) as an unconventional reservoir in southwestern Mississippi. The basal high resistivity zone has a higher proportion of Type II sedimentary organic matter than the overlying TMS, indicating it is more prone to oil generation. Optical petrography and electron microscopy reveal a heterogeneous clay matrix with ubiquitous pyrite grains, quartz, feldspar, glaucony, foraminifera, shell fragments, and rarer occurrences of apatite and crinoid fragments as well as liptinite, alginite, inertinite, and vitrinite. Our petrographic observations suggest that higher abundances of detrital quartz grains coupled with minimal authigenic cements result in higher porosity and permeability. However, the TMS is also more clay-rich than other unconventional shale oil and gas plays, which can impair the effectiveness of hydraulic fracture stimulation. Thin section observations reveal alternating clay and calcium carbonate laminae that are interpreted to reflect changes in sediment flux. Planktonic foraminifera indicate an overlying oxygenated water column while benthic inoceramid fragments and pervasive authigenic pyrite suggest anoxic or dysoxic bottom water conditions. Apatite fragments in thin section suggest mixing events and an influx of nutrient-rich sediments. Overall, these observations suggest that a variety of paleodepositional environments occurred in the TMS and the lithofacies diversity resulting from these small-scale depositional cycles makes it difficult to determinatively identify areas conducive to enhanced economic hydrocarbon recovery.

Mississippi, Lousianna↗
USGS2011

Bibliography of literature pertaining to Long Valley Caldera and associated volcanic fields

On May 25-27, 1980, Long Valley caldera was rocked by four M=6 earthquakes that heralded the onset of a wave of seismic activity within the caldera which has continued through the present. Unrest has taken the form of seismic swarms, uplift of the resurgent dome, and areas of vegetation killed by increased CO2 emissions, all interpreted as resulting from magma injection into different levels beneath the caldera, as well as beneath Mammoth Mountain along the southwest rim of the caldera. Continuing economic development in the Mammoth Lakes area has swelled the local population, increasing the risk to people and property if an eruption were to occur. The U.S. Geological Survey (USGS) has been monitoring geophysical activity in the Long Valley area since the mid-1970s and continues to track the unrest in real time with a sophisticated network of geophysical sensors. Hazards information obtained by this monitoring is provided to local, State, and Federal officials and to the public through the Long Valley Observatory. The Long Valley area also was scientifically important before the onset of current unrest. Lying at the eastern foot of the Sierra Nevada, the deposits from this active volcanic system have provided fertile ground for research into Neogene tectonics, Quaternary geology and geomorphology, regional stratigraphy, and volcanology. In the early 1970s, intensive studies of the area began through the USGS Geothermal Investigations Program, owing to the presence of a large young silicic volcanic system. The paroxysmal eruption of Long Valley caldera about 760,000 years ago produced the Bishop Tuff and associated Bishop ash. The Bishop Tuff is a well-preserved ignimbrite deposit that has continued to provide new and developing insights into the dynamics of ignimbrite-forming eruptions. Another extremely important aspect of the Bishop Tuff is that it is the oldest known normally magnetized unit of the Brunhes Chron. Thus, the age of the Bishop Tuff is used to define the beginning of the Brunhes Chron and helps constrain the Brunhes-Matuyama boundary. The Bishop ash, which was dispersed as far east as Nebraska, Kansas, and Texas, provides an important tephrostratigraphic marker throughout the Western United States. The obsidian domes of both the Mono and Inyo Craters, which were produced by rhyolitic eruptions in the past 40,000 years, have been well studied, including extensive scientific drilling through the domes. Exploratory drilling to 3-km depth on the resurgent dome and subsequent instrumentation of the Long Valley Exploratory Well (LVEW) have led to a number of important new insights. Scientific drilling also has been done within the Casa Diablo geothermal field, which, aside from drilling, has been commercially developed and is currently feeding 40 MW of power into the Southern California Edison grid. Studies in all the above-mentioned volcanic fields have contributed to the extensive scientific literature published on the Long Valley region. Although most of this scientific literature has been published since 1970, a significant amount of historical literature extends backward to the late 1800s. The purpose of this bibliography is to compile references pertaining to the Long Valley region from all time periods and all Earth science fields into a single listing, thus providing an easily accessible guide to the published literature for current and future researchers.

Open-File Report↗
USGS1976

A reconnaissance study of the uranium and thorium contents of plutonic rocks of the southeastern Seward Peninsula, Alaska

Large granitic Cretaceous plutons are exposed along and adjacent to an arcuate belt of igneous and high-grade raetamorphic rocks in the southeastern Seward Peninsula of Alaska. Reconnaissance studies of these plutons have shown that the Darby pluton has well above average amounts of uranium and thorium (11.2 ppm and 58.7 ppm, respectively), the Kachauik pluton contains average to above average uranium and thorium (5.7 ppm and 22.5 ppm, respectively), and the Bendeleben pluton contains average amounts of uranium and thorium (3.4 ppm and 16.7 ppm, respectively). The three plutons show compositional and textural differences indicative of different source materials that may have controlled the distribution of uranium and thorium. The high uranium and thorium contents of the Darby pluton, similar to those of the Conway Granite of New Hampshire which has been mentioned as a possible low-grade thorium resource, suggest that this pluton may be a favorable area for economic concentrations of uranium and thorium.

Alaska↗
USGS2012

Geologic framework for the national assessment of carbon dioxide storage resources

The 2007 Energy Independence and Security Act (Public Law 110–140) directs the U.S. Geological Survey (USGS) to conduct a national assessment of potential geologic storage resources for carbon dioxide (CO 2 ) and to consult with other Federal and State agencies to locate the pertinent geological data needed for the assessment. The geologic sequestration of CO 2 is one possible way to mitigate its effects on climate change. The methodology used for the national CO 2 assessment (Open-File Report 2010-1127; http://pubs.usgs.gov/of/2010/1127/) is based on previous USGS probabilistic oil and gas assessment methodologies. The methodology is non-economic and intended to be used at regional to subbasinal scales. The operational unit of the assessment is a storage assessment unit (SAU), composed of a porous storage formation with fluid flow and an overlying sealing unit with low permeability. Assessments are conducted at the SAU level and are aggregated to basinal and regional results. This report identifies and contains geologic descriptions of SAUs in separate packages of sedimentary rocks within the assessed basin and focuses on the particular characteristics, specified in the methodology, that influence the potential CO 2 storage resource in those SAUs. Specific descriptions of the SAU boundaries as well as their sealing and reservoir units are included. Properties for each SAU such as depth to top, gross thickness, net porous thickness, porosity, permeability, groundwater quality, and structural reservoir traps are provided to illustrate geologic factors critical to the assessment. Although assessment results are not contained in this report, the geologic information included here will be employed, as specified in the methodology, to calculate a statistical Monte Carlo-based distribution of potential storage space in the various SAUs. Figures in this report show SAU boundaries and cell maps of well penetrations through the sealing unit into the top of the storage formation. Wells sharing the same well borehole are treated as a single penetration. Cell maps show the number of penetrating wells within one square mile and are derived from interpretations of incompletely attributed well data, a digital compilation that is known not to include all drilling. The USGS does not expect to know the location of all wells and cannot guarantee the amount of drilling through specific formations in any given cell shown on cell maps.

Open-File Report↗
USGS1997

Natural disasters: forecasting economic and life losses

Events such as hurricanes, earthquakes, floods, tsunamis, volcanic eruptions, and tornadoes are natural disasters because they negatively impact society, and so they must be measured and understood in human-related terms. At the U.S. Geological Survey, we have developed a new method to examine fatality and dollar-loss data, and to make probabilistic estimates of the frequency and magnitude of future events. This information is vital to large sectors of society including disaster relief agencies and insurance companies.

Fact Sheet↗
USGS2014

Characterization of potential mineralization in Afghanistan: four permissive areas identified using imaging spectroscopy data

As part of the U.S. Geological Survey and Department of Defense Task Force for Business and Stability Operations natural resources revitalization activities in Afghanistan, four permissive areas for mineralization, Bamyan 1, Farah 1, Ghazni 1, and Ghazni 2, have been identified using imaging spectroscopy data. To support economic development, the areas of potential mineralization were selected on the occurrence of selected mineral assemblages mapped using the HyMap™ data (kaolinite, jarosite, hydrated silica, chlorite, epidote, iron-bearing carbonate, buddingtonite, dickite, and alunite) that may be indicative of past mineralization processes in areas with limited or no previous mineral resource studies. Approximately 30 sites were initially determined to be candidates for areas of potential mineralization. Additional criteria and material used to refine the selection and prioritization process included existing geologic maps, Landsat Thematic Mapper data, and published literature. The HyMapTM data were interpreted in the context of the regional geologic and tectonic setting and used the presence of alteration mineral assemblages to identify areas with the potential for undiscovered mineral resources. Further field-sampling, mapping, and supporting geochemical analyses are necessary to fully substantiate and verify the specific deposit types in the four areas of potential mineralization.

Bamyan;Farah;Ghazni↗
USGS2020

Framework for a long-term strategic plan for the Capital Area Groundwater Conservation Commission

The Capital Area Groundwater Conservation Commission oversees the use of groundwater in six parishes in Louisiana. In carrying out its statutory responsibilities and authorities, the Commission recognizes the complexity of its decisions: the long-term objectives it is seeking are multifaceted; the actions it can choose from are numerous and interdependent; and the understanding of the hydrogeological, economic, and social systems affected by its actions is limited. To navigate this complexity, the Commission is developing a long-term strategic plan to guide its activities and to serve as a primary mode of communication to stakeholders and the public. The long-term strategic plan is intended to consider actions and outcomes over at least the next 50 years within the 6 parishes in the Commission’s jurisdiction and related to all the confined aquifers in the 3000 feet below the district. The primary purposes of the plan are to promote long-term sustainability of groundwater extraction, continuity of operations of the Commission, long-term planning by water users, and clear communication with the public. The plan will describe specific management actions to be taken over time by the Commission, and the conditions under which those actions are to be taken. It will include intermediate milestones the Commission intends to achieve on the way toward achieving its long-term objectives. The actions under consideration include regulation and monitoring of groundwater withdrawal, mitigation of the environmental effects of withdrawal, support of relevant scientific studies, as well as work with partner agencies to implement measures to conserve, develop, and supplement groundwater resources. The plan will have greater detail about short-term actions than mid-term and long-term actions, and the Commission anticipates updating the plan periodically to adapt to changing circumstances and knowledge. To develop its long-term strategic plan, the Commission is working with The Water Institute of the Gulf and the U.S. Geological Survey using a facilitated process based on the principles of structured decision making (Gregory et al., 2012). This document outlines the framework for the strategic plan by describing the legal, economic, and scientific context for the plan, the fundamental objectives the Commission seeks to achieve in the long term, and the strategic alternatives it is considering.

Report↗
USGS2020

An integrated feasibility study of reservoir thermal energy storage in Portland, Oregon, USA

In regions with long cold overcast winters and sunny summers, Deep Direct-Use (DDU) can be coupled with Reservoir Thermal Energy Storage (RTES) technology to take advantage of pre-existing subsurface permeability to save summer heat for later use during cold seasons. Many aquifers worldwide are underlain by permeable regions (reservoirs) containing brackish or saline groundwater that has limited beneficial use due to poor water quality. We investigate the utility of these relatively deep, slow flowing reservoirs for RTES by conducting an integrated feasibility study in the Portland Basin, Oregon, USA, developing methods and obtaining results that can be widely applied to groundwater systems elsewhere. As a case study, we have conducted an economic and social cost-benefit analysis for the Oregon Health and Science University (OHSU), a teaching hospital that is recognized as critical infrastructure in the Portland Metropolitan Area. Our investigation covers key factors that influence feasibility including 1) the geologic framework, 2) heat and fluid flow modeling, 3) capital and maintenance costs, 4) the regulatory framework, and 5) operational risks. By pairing a model of building seasonal heat demand with an integrated model of RTES resource supply, we determine that the most important factors that influence RTES efficacy in the study area are operational schedule, well spacing, the amount of summer heat stored (in our model, a function of solar array size), and longevity of the system. Generally, heat recovery efficiency increases as the reservoir and surrounding rocks warm, making RTES more economical with time. Selecting a base-case scenario, we estimate a levelized cost of heat (LCOH) to compare with other sources of heating available to OHSU and find that it is comparable to unsubsidized solar and nuclear, but more expensive than natural gas. Additional benefits of RTES include energy resiliency in the event that conventional energy supplies are disrupted (e.g., natural disaster) and a reduction in fossil fuel consumption resulting in a smaller carbon footprint. Key risks include reservoir heterogeneity and a possible reduction in permeability through time due to scaling (mineral precipitation). Lastly, a map of thermal energy storage capacity for the Portland Basin yields a total of 87,000 GWh, suggesting tremendous potential for RTES in the Portland Metropolitan Area.

Oregon↗
USGS2006

Saline ground water — A little used and unmapped resource

Vast quantities of saline ground water await new commercial uses and economical demineralization processes for recognition as a valuable resource . Saline ground water is more widely distributed than any other natural resource , occurring throughout the United States and in geologic formations ranging from the oldest to the youngest. The Coastal Plain has the greatest reserve of fresh water in the country, but at depths ranging from a few feet to about 3,500 feet most of the fresh‐ water aquifers also contain large quantities of brackish water . Paleozoic formations in the east‐central United States have long been producers of saline water as commercial brines and in association with oil and gas. The volume of saline ground water perhaps exceeds the fresh ground ‐ water supply in the Great Plains Region. The greater part of the Western Mountain Region is generally deficient in fresh ground water ; however, saline water is present in highly permeable deposits in numerous closed basins and along saline streams. In each of these major ground ‐ water regions small to very large amounts of saline water can be pumped from wells ranging from a few tens of feet to several thousand feet in depth. Knowledge of saline water distribution is general and inadequate, having been attained as a by‐product of investigations of fresh‐ water supplies. This knowledge should be expanded as technological advances in demineralization processes enhance the importance of saline water for potential supply in numerous water ‐deficient areas.

Groundwater↗
USGS1982

Reconnaissance geology of the Wadi Dhahaban Quadrangle, sheet 18/41 D, Kingdom of Saudi Arabia

The Wadi Dhahaban quadrangle (sheet 18/41 D) lies between lat 18?00? and 18?30' N. and long 41?30' and 42?00' E. and encompasses an area of 2,937 km2 located along the Red Sea coast and includes part of the escarpment-mountains province. The geologic formations exposed in the quadrangle are comprised of Precambrian layered and intrusive rocks, Tertiary gabbro dikes, Quaternary basaltic lavas and pyroclastic rocks, and Quaternary surficial deposits. No economic mineral deposits have been found. The Precambrian rocks include layered sedimentary and volcanic rocks that have been assigned to the Baish, Bahah, and Ablah groups. They have been folded, metamorphosed, and invaded by three separate intrusions. The Precambrian rocks are cut by Miocene gabbro dikes that were intruded during the initial stages of the opening of the Red Sea rift. The Quaternary rocks include basalt, and coastal, pediment, and alluvial deposits of various kinds. The area is of special interest because of its unique display of the Tertiary and Quaternary basaltic volcanism that was associated with the opening of the Red Sea rift and that has continued in other parts of the Kingdom until historic times.

Open-File Report↗
USGS1985

Lognormal field size distributions as a consequence of economic truncation

The assumption of lognormal (parent) field size distributions has for a long time been applied to resource appraisal and evaluation of exploration strategy by the petroleum industry. However, frequency distributions estimated with observed data and used to justify this hypotheses are conditional. Examination of various observed field size distributions across basins and over time shows that such distributions should be regarded as the end result of an economic filtering process. Commercial discoveries depend on oil and gas prices and field development costs. Some new fields are eliminated due to location, depths, or water depths. This filtering process is called economic truncation. Economic truncation may occur when predictions of a discovery process are passed through an economic appraisal model. We demonstrate that (1) economic resource appraisals, (2) forecasts of levels of petroleum industry activity, and (3) expected benefits of developing and implementing cost reducing technology are sensitive to assumptions made about the nature of that portion of (parent) field size distribution subject to economic truncation. ?? 1985 Plenum Publishing Corporation.

Journal of the International Association for Mathe↗
USGS1961

Geologic summary of the Appalachian Basin, with reference to the subsurface disposal of radioactive waste solutions

The Appalachian basin is an elongate depression in the crystalline basement complex which contains a great volume of predominantly sedimentary stratified rocks. As defined in this paper it extends from the Adirondack Mountains in New York to central Alabama. From east to west it extends from the west flank of the Blue Ridge Mountains to the crest of the Findlay and Cincinnati arches and the Nashville dome. It encompasses an area of about 207,000 square miles, including all of West Virginia and parts of New York, New Jersey, Pennsylvania, Ohio, Maryland, Virginia, Kentucky, Tennessee, North Carolina, Georgia, and Alabama. The stratified rocks that occupy the basin constitute a wedge-shaped mass whose axis of greatest thickness lies close to and parallel to the east edge of the basin. The maximum thickness of stratified rocks preserved in any one part of the basin today is between 35,000 and 40,000 feet. The volume of the sedimentary rocks is approximately 510,000 cubic miles and of volcanic rocks is a few thousand cubic miles. The sedimentary rocks are predominantly Paleozoic in age, whereas the volcanic rocks are predominantly Late Precambrian. On the basis of gross lithology the stratified rocks overlying the crystalline basement complex can be divided into nine vertically sequential units, which are designated "sequences" in this report. The boundaries between contiguous sequences do not necessarily coincide with the commonly recognized boundaries between systems or series. All sequences are grossly wedge shaped, being thickest along the eastern margin of the basin and thinnest along the western margin. The lowermost unit the Late Precambrian stratified sequence is present only along part of the eastern margin of the basin, where it lies unconformably on the basement complex. It consists largely of volcanic tuffs and flows but contains some interbedded sedimentary rocks. The Late Precambrian sequence is overlain by the Early Cambrian clastic sequence. Where the older sequence is absent, the Early Cambrian sequence rests on the basement complex. Interbedded fine- to coarse-grained noncarbonate detrital rocks comprise the bulk of the sequence, but some volcanic and carbonate rocks are included. Next above is the Cambrian-Ordovician carbonate sequence which consists largely of limestone and dolomite. Some quartzose sandstone is present in the lower part in the western half of the basin, and much shale is present in the upper part in the southeast part of the basin. The next higher sequence is the Late Ordovician clastic sequence, which consists largely of shale, siltstone, and sandstone. Coarse-grained light-gray to red rocks are common in the sequence along the eastern side of the basin, whereas fine-grained dark-gray to black calcareous rocks are common along the west side. The Late Ordovician clastic sequence is overlain unconformably in many places by the Early Silurian clastic sequence. The latter comprises a relatively thin wedge of coarse-grained clastic rocks. Some of the most prolific oil- and gas-producing sandstones in the Appalachian basin are included. Among these are the "Clinton" sands of Ohio, the Medina Sandstones of New York and Pennsylvania, and the Keefer or "Big Six" Sandstone of West Virginia and Kentucky. Conformably overlying the Early Silurian clastic sequence is the Silurian-Devonian carbonate sequence, which consists predominantly of limestone and dolomite. It also contains a salt-bearing unit in the north-central part of the basin and a thick wedge of coarse-grained red beds in the northeastern part. The sequence is absent in much of the southern part of the basin. Large volumes of gas and much oil are obtained from some of its rocks, especially from the Oriskany Sandstone and the Huntersville Ghert. The Silurian-Devonian carbonate sequence is abruptly overlain by the Devonian clastic sequence a thick succession of interbedded shale, mudrock, siltstone, and sandstone. Colors range from predominantly purple and red in the northeastern part of the basin to predominantly dark gray and black in the southwestern part. Many rocks in the upper part contain hydrocarbons in commercial quantities. The next higher sequence is a heterogeneous succession that comprises most rocks of Mississippian age in the basin. It is composed largely of fine-grained to very coarse-grained noncalcareous clastic rocks in the northern half of the basin, and largely of carbonate rocks in the southern part. Large quantities of oil and gas are produced from the sequence. The youngest sequence consists of coarse-grained clastic rocks largely of Pennsylvanian age. In the center of the basin a relatively small volume of lithologically similar rocks of Permian age are included. The sequence has been intensively mined for coal throughout most of its extent. The waste-disposal possibilities of the stratified rocks in the Appalachian basin are considered in terms of the following: 1) gross lithology of the sequences; 2) general lithology of the rock units composing the sequences; and 3) the structural attitudes of the sequences in different parts of the basin. The degree of exploitation of economically significant mineral* resources is considered briefly where such exploitation may affect waste-disposal possibilities. Hydrologic aspects are not in general considered. Based largely on consideration of the above geologic factors the following types of reservoirs associated with particular geologic environments offer some prospects for the disposal of radioactive waste solutions. They are: 1) artificially created cavities in thick salt beds; 2) artificially fractured thin lenticular sandstone bodies isolated in shale or mudrock sequences; 3) portions of thick noncarbonate clastic sequences possessing appreciable natural porosity and permeability; 4) thin clastic units (with natural or artificially created openings) in the plate of a thrust fault overlain by impermeable strata. Considered in its entirety the Late Ordovician clastic sequence appears to have a greater number of favorable geologic factors for waste-disposal purposes than the others. The Early Silurian clastic sequence, the Silurian-Devonian carbonate sequence, and the Devonian clastic sequence offer fewer possibilities. The Late Precambrian stratified sequence, Early Cambrian, and the Cambrian-Ordovician carbonate sequence offer few possibilities. The Mississippian and Pennsylvanian sequences appear to be generally unsuitable.

Appalachian Basin↗
USGS1961

Geologic summary of the Appalachian basin, with reference to the subsurface disposal of radioactive waste solutions

The Appalachian basin is an elongate depression in the crystalline basement complex which contains a great volume of predominantly sedimentary stratified rocks. As defined in this paper it extends from the Adirondack Mountains in New York to central Alabama. From east to west it extends from the west flank of the Blue Ridge Mountains to the crest of the Findlay and Cincinnati arches and the Nashville dome. It encompasses an area of about 207,000 square miles, including all of West Virginia and parts of New York, New Jersey, Pennsylvania, Ohio, Maryland, Virginia, Kentucky, Tennessee, North Carolina, Georgia, and Alabama. The stratified rocks that occupy the basin constitute a wedge-shaped mass whose axis of greatest thickness lies close to and parallel to the east edge of the basin. The maximum thickness of stratified rocks preserved in any one part of the basin today is between 35,000 and 40,000 feet. The volume of the sedimentary rocks is approximately 510,000 cubic miles and of volcanic rocks is a few thousand cubic miles. The sedimentary rocks are predominantly Paleozoic in age, whereas the volcanic rocks are predominantly Late Precambrian. On the basis of gross lithology the stratified rocks overlying the crystalline basement complex can be divided into nine vertically sequential units, which are designated "sequences" in this report. The boundaries between contiguous sequences do not necessarily coincide with the commonly recognized boundaries between systems or series. All sequences are grossly wedge shaped, being thickest along the eastern margin of the basin and thinnest along the western margin. The lowermost unit the Late Precambrian stratified sequence is present only along part of the eastern margin of the basin, where it lies unconformably on the basement complex. It consists largely of volcanic tuffs and flows but contains some interbedded sedimentary rocks. The Late Precambrian sequence is overlain by the Early Cambrian clastic sequence. Where the older sequence is absent, the Early Cambrian sequence rests on the basement complex. Interbedded fine- to coarse-grained noncarbonate detrital rocks comprise the bulk of the sequence, but some volcanic and carbonate rocks are included. Next above is the Cambrian-Ordovician carbonate sequence which consists largely of limestone and dolomite. Some quartzose sandstone is present in the lower part in the western half of the basin, and much shale is present in the upper part in the southeast part of the basin. The next higher sequence is the Late Ordovician clastic sequence, which consists largely of shale, siltstone, and sandstone. Coarse-grained light-gray to red rocks are common in the sequence along the eastern side of the basin, whereas fine-grained dark-gray to black calcareous rocks are common along the west side. The Late Ordovician clastic sequence is overlain unconformably in many places by the Early Silurian clastic sequence. The latter comprises a relatively thin wedge of coarse-grained clastic rocks. Some of the most prolific oil- and gas-producing sandstones in the Appalachian basin are included. Among these are the "Clinton" sands of Ohio, the Medina Sandstones of New York and Pennsylvania, and the Keefer or "Big Six" Sandstone of West Virginia and Kentucky. Conformably overlying the Early Silurian clastic sequence is the Silurian-Devonian carbonate sequence, which consists predominantly of limestone and dolomite. It also contains a salt-bearing unit in the north-central part of the basin and a thick wedge of coarse-grained red beds in the northeastern part. The sequence is absent in much of the southern part of the basin. Large volumes of gas and much oil are obtained from some of its rocks, especially from the Oriskany Sandstone and the Huntersville Ghert. The Silurian-Devonian carbonate sequence is abruptly overlain by the Devonian clastic sequence a thick succession of interbedded shale, mudrock, siltstone, and sandstone. Colors range from predominantly purple and red in the northeastern part of the basin to predominantly dark gray and black in the southwestern part. Many rocks in the upper part contain hydrocarbons in commercial quantities. The next higher sequence is a heterogeneous succession that comprises most rocks of Mississippian age in the basin. It is composed largely of fine-grained to very coarse-grained noncalcareous clastic rocks in the northern half of the basin, and largely of carbonate rocks in the southern part. Large quantities of oil and gas are produced from the sequence. The youngest sequence consists of coarse-grained clastic rocks largely of Pennsylvanian age. In the center of the basin a relatively small volume of lithologically similar rocks of Permian age are included. The sequence has been intensively mined for coal throughout most of its extent. The waste-disposal possibilities of the stratified rocks in the Appalachian basin are considered in terms of the following: 1) gross lithology of the sequences; 2) general lithology of the rock units composing the sequences; and 3) the structural attitudes of the sequences in different parts of the basin. The degree of exploitation of economically significant mineral* resources is considered briefly where such exploitation may affect waste-disposal possibilities. Hydrologic aspects are not in general considered. Based largely on consideration of the above geologic factors the following types of reservoirs associated with particular geologic environments offer some prospects for the disposal of radioactive waste solutions. They are: 1) artificially created cavities in thick salt beds; 2) artificially fractured thin lenticular sandstone bodies isolated in shale or mudrock sequences; 3) portions of thick noncarbonate clastic sequences possessing appreciable natural porosity and permeability; 4) thin clastic units (with natural or artificially created openings) in the plate of a thrust fault overlain by impermeable strata. Considered in its entirety the Late Ordovician clastic sequence appears to have a greater number of favorable geologic factors for waste-disposal purposes than the others. The Early Silurian clastic sequence, the Silurian-Devonian carbonate sequence, and the Devonian clastic sequence offer fewer possibilities. The Late Precambrian stratified sequence, Early Cambrian, and the Cambrian-Ordovician carbonate sequence offer few possibilities. The Mississippian and Pennsylvanian sequences appear to be generally unsuitable.

Appalachian Basin↗
USGS2003

Sediment-hosted copper deposits of the world: Deposit models and database

Introduction This publication contains four descriptive models and four grade-tonnage models for sediment hosted copper deposits. Descriptive models are useful in exploration planning and resource assessment because they enable the user to identify deposits in the field and to identify areas on geologic and geophysical maps where deposits could occur. Grade and tonnage models are used in resource assessment to predict the likelihood of different combinations of grades and tonnages that could occur in undiscovered deposits in a specific area. They are also useful in exploration in deciding what deposit types meet the economic objectives of the exploration company. The models in this report supersede the sediment-hosted copper models in USGS Bulletin 1693 (Cox, 1986, and Mosier and others, 1986) and are subdivided into a general type and three subtypes. The general model is useful in classifying deposits whose features are obscured by metamorphism or are otherwise poorly described, and for assessing regions in which the geologic environments are poorly understood. The three subtypes are based on differences in deposit form and environments of deposition. These differences are described under subtypes in the general model. Deposit models are based on the descriptions of geologic environments and physical characteristics, and on metal grades and tonnages of many individual deposits. Data used in this study are presented in a database representing 785 deposits in nine continents. This database was derived partly from data published by Kirkham and others (1994) and from new information in recent publications. To facilitate the construction of grade and tonnage models, the information, presented by Kirkham in disaggregated form, was brought together to provide a single grade and a single tonnage for each deposit. Throughout the report individual deposits are defined as being more than 2,000 meters from the nearest adjacent deposit. The deposit models are presented here as a PDF file. The database can be most conveniently read in FileMaker Pro. For those who do not have the FileMaker application, Microsoft-Excel, tab-delimited-ASCII and comma-separated-value files are included. The reader may be interested in a similar publication on porphyry copper deposits (Singer and others, 2005) also available online. The Google Earth image is not intended to be viewed at the highest possible magnification because the resolution of the database is plus or minus two kilometers. At extreme zoom settings, the deposit locations may not coincide with the Google-Earth images of the mine workings.

Open-File Report↗