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USGS1986

USGS research on energy resources, 1986; program and abstracts

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

Circular↗

USGS1998

Geochemistry of the northern Atlantic Coastal Plain aquifer system

Sediments of the northern Atlantic Coastal Plain comprise a complex multiaquifer flow system. On a large scale (greater than 500 square miles) ground water in this system evolves from predominantly calcium magnesium bicarbonate water with a low dissolved-solids content and low pH, near outcrop-recharge areas, to predominantly sodium bicarbonate water with a high-dissolved solids content and high pH, downgradient. This sodium bicarbonate water then grades into a sodium chloride water. This large-scale predictable progression of hydrochemical facies results from the summation of many smaller scale geochemical processes that chiefly depend on the sedimentary depositional environments of the aquifers.

Northern Atlantic coastal plain↗

USGS2000

Estimating the impacts of oil spills on polar bears

The polar bear is the apical predator and universal symbol of the Arctic. They occur throughout the Arctic marine environment wherever sea ice is prevalent. In the southern Beaufort Sea, polar bears are most common within the area of the outer continental shelf, where the hunt for seals along persistent leads and openings in the ice. Polar bears are a significant cultural and subsistence component of the lifestyles of indigenous people. They may also be one of the most important indicators of the health of the Arctic marine environment. Polar bears have a late age of maturation, a long inter0brth period, and small liter sizes. These life history features make polar bear populations susceptible to natural and human perturbations. Petroleum exploration and extraction have been in progress along the coast of northern Alaska for more than 25 years. Until recently, most activity has taken place on the mainland or at sites connected to the shore by a causeway. In 1999, BP Exploration-Alaska began constructing the first artificial production island designed to transport oil through sub-seafloor pipelines. Other similar projects have been proposed to begin in the next several years. The proximity of oil exploration and development to principal polar bear habitats raises concerns, and with the advent of true off-shore development projects, these concerns are compounded. Contact with oil and other industrial chemicals by polar bears, through grooming, consumption of tainted food, or direct consumption of chemicals, may be lethal. The active ice where polar bears hunt is also where spilled oil may be expected to concentrate during spring break-up and autumn freeze-up. Because of this, we could expect that an oil spill in the waters and ice of the continental shelf would have profound effects on polar bears. Assessments of the effects of spills, however, have not been done. This report described a promising method for estimating the effects of oil spills on polar bears in the Arctic marine environment. It uses enough real data to illuminate necessary calculations and illustrate the value of the methods. The results and conclusions presented here are only examples of possible scenarios resulting from a new estimation method. Final assessment of the potential impacts to polar bears of an oil spill remains a work in progress.

Alaska, Northwest Territories, Yukon↗

USGS1997

Relation of the lower Pennsylvanian unconformity to a mid-carboniferous eustatic event in the eastern United States

Two contrasting concepts specifying the age and duration of the hiatus resulting from a mid-Carboniferous eustatic event in the eastern United States are based on different evidence. The original model indicated that the hiatus is at an unconformity in cratonic areas that was assumed to coincide with the Mississippian-Pennsylvanian boundary at the contact between the Mississippian Bluestone Formation and the Pennsylvanian Pocahontas Formation in the Appalachian foreland basin. This concept was adhered to exclusively until 1969 and continues to reappear in reports dealing with global correlations and division of the Carboniferous into the Mississippian and Pennsylvanian Systems. This division is at a major eustatic event that supposedly occurred at about 330 Ma in scattered parts of the world, including the Appalachian basin. An alternative concept, fully supported by geologic mapping and biostratigraphic studies, indicates that the unconformity and associated hiatus are much younger because they originate in the Appalachian foreland basin in the lower part (upper Namurian) of the Lower Pennsylvanian New River Formation, about 260 m above the Mississippian-Pennsylvanian boundary. The duration of this hiatus increases in a northwesterly direction onto the cratonic shelf because the unconformity progressively truncated the underlying Lower Pennsylvanian and Upper Mississippian successions. The westward onlap of Pennsylvanian strata onto the eroded surface resulted in a hiatus from the Early Mississippian (Tournaisian) to the Middle Pennsylvanian (Westphalian B). The systemic boundary, which is in a depositional continuous sequence of strata in the Appalachian foreland basin, was correlated biostratigraphically by Pfefferkorn and Gillespie in 1982 with Gothan's "Florensprung" (floral break) described in 1913 at the Namurian A-B boundary in the Upper Silesian basin. An intra-Namurian erosive event was noted also in the Upper Silesian basin by Havlena, who reported in 1982 that an intra-Namurian erosive contact occurs well above the Florensprung. The origin of the Florensprung in depositional continuous strata has been attributed to tectonism, environment, or climate. However, spherules found in depositional continuous strata near the Mississippian-Pennsylvanian boundary in the Appalachian basin indicate that the effect of an asteroid impact may be the underlying cause for the biodiversity noted at the systemic boundary.

Pennsylvania, Mississippi↗

USGS2015

Reintroduction of Lake Sturgeon ( Acipenser fulvescens ) into the St. Regis River, NY: Post-release assessment of habitat use and growth

One of the depleted endemic fish species of the Great Lakes, Acipenser fulvescens (Lake Sturgeon), has been the target of extensive conservation efforts. One strategy is reintroduction into historically productive waters. The St. Regis River, NY, represents one such adaptive-management effort, with shared management between New York and the St. Regis Mohawk Tribe. Between 1998 and 2004, a total of 4977 young-of-year Lake Sturgeon were released. Adaptive management requires intermediate progress metrics. During 2004 and 2005, we measured growth, habitat use, and survivorship metrics of the released fish. We captured a total of 95 individuals of all stocked ages. Year-class minimal-survival rates ranged from 0.19–2.1%. The size-at-age and length/biomass relationships were comparable to those reported for juveniles in other Great Lakes waters. These intermediate assessment metrics can provide feedback to resource managers who make restoration-program decisions on a much shorter time-scale than the time-frame in which the ultimate goal of a self-sustaining population can be attained.

New York↗

USGS2012

Dissolved oxygen analysis, TMDL model comparison, and particulate matter shunting—Preliminary results from three model scenarios for the Klamath River upstream of Keno Dam, Oregon

Efforts are underway to identify actions that would improve water quality in the Link River to Keno Dam reach of the Upper Klamath River in south-central Oregon. To provide further insight into water-quality improvement options, three scenarios were developed, run, and analyzed using previously calibrated CE-QUAL-W2 hydrodynamic and water-quality models. Additional scenarios are under development as part of this ongoing study. Most of these scenarios evaluate changes relative to a "current conditions" model, but in some cases a "natural conditions" model was used that simulated the reach without the effect of point and nonpoint sources and set Upper Klamath Lake at its Total Maximum Daily Load (TMDL) targets. These scenarios were simulated using a model developed by the U.S. Geological Survey (USGS) and Watercourse Engineering, Inc. for the years 2006–09, referred to here as the "USGS model." Another model of the reach was developed by Tetra Tech, Inc. for years 2000 and 2002 to support the Klamath River TMDL process; that model is referred to here as the "TMDL model." The three scenarios described in this report included (1) an analysis of whether this reach of the Upper Klamath River would be in compliance with dissolved oxygen standards if sources met TMDL allocations, (2) an application of more recent datasets to the TMDL model with comparison to results from the USGS model, and (3) an examination of the effect on dissolved oxygen in the Klamath River if particulate material were stopped from entering Klamath Project diversion canals. Updates and modifications to the USGS model are in progress, so in the future these scenarios will be reanalyzed with the updated model and the interim results presented here will be superseded. Significant findings from this phase of the investigation include: * The TMDL analysis used depth-averaged dissolved oxygen concentrations from model output for comparison with dissolved oxygen standards. The Oregon dissolved oxygen standards do not specify whether the numeric criteria are based on depth-averaged dissolved oxygen concentration; this was an interpretation of the standards rule by the Oregon Department of Environmental Quality (ODEQ). In this study, both depth-averaged and volume-averaged dissolved oxygen concentrations were calculated from model output. Results showed that modeled depth-averaged concentrations typically were lower than volume-averaged dissolved oxygen concentrations because depth-averaging gives a higher weight to small volume areas near the channel bottom that often have lower dissolved oxygen concentrations. Results from model scenarios in this study are reported using volume-averaged dissolved oxygen concentrations. * Under all scenarios analyzed, violations of the dissolved oxygen standard occurred most often in summer. Of the three dissolved oxygen criteria that must be met, the 30-day standard was violated most frequently. Under the base case (current conditions), fewer violations occurred in the upstream part of the reach. More violations occurred in the down-stream direction, due in part to oxygen demand from the decay of algae and organic matter from Link River and other inflows. * A condition in which Upper Klamath Lake and its Link River outflow achieved Upper Klamath Lake TMDL water-quality targets was most effective in reducing the number of violations of the dissolved oxygen standard in the Link River to Keno Dam reach of the Klamath River. The condition in which point and nonpoint sources within the Link River to Keno Dam reach met Klamath River TMDL allocations had no effect on dissolved oxygen compliance in some locations and a small effect in others under current conditions. On the other hand, meeting TMDL allocations for nonpoint and point sources was predicted to be important in meeting dissolved oxygen criteria when Upper Klamath Lake and Link River also met Upper Klamath TMDL water-quality targets. * The location of greatest dissolved oxygen improvement from nutrient and organic matter reductions was downstream from point and nonpoint source inflows because time and distance are required for decay to occur and for oxygen demand to be exerted. * After assessing compliance with dissolved oxygen standards at all 102 model segments in the Link River to Keno Dam reach, it was determined that the seven locations used by ODEQ appear to be a representative subset of the reach for dissolved oxygen analysis. * The USGS and TMDL models were qualitatively compared by running both models for the 2006–09 period but preserving the essential characteristics of each, such as organic matter partitioning, bathymetric representation, and parameter rates. The analysis revealed that some constituents were not greatly affected by the differing algorithms, rates, and assumptions in the two models. Conversely, other constituents, especially organic matter, were simulated differently by the two models. Organic matter in this river system is best represented by a mixture of relatively labile particulate material and a substantial concentration of refractory dissolved material. In addition, the use of a first-order sediment oxygen demand, as in the USGS model, helps to capture the seasonal and dynamic effect of settled organic and algal material. * Simulation of shunting (diverting) particulate material away from the intake of four Klamath Project diversion canals, so that the material stayed in the river and out of the Project area, caused higher concentrations of particulate material to occur in the river. In all cases modeled, the increase in in-river particulate material also produced decreased dissolved oxygen concentrations and an increase in the number of days when dissolved oxygen standards were violated. * If particulate material were shunted back into the river at the Klamath Project diversion canals, less organic matter and nutrients would be taken into the Klamath Project area and the Lost River basin, resulting in return flows to the Klamath River via Lost River Diversion Channel that may have reduced nutrient concentrations. Model scenarios bracketing potential end-member nutrient concentrations showed that the composition of the return flows had little to no effect on dissolved oxygen compliance under simulated conditions.

Oregon↗

USGS2000

Geophysical, archaeological and historical evidence support a solar-output model for climate change

Although the processes of climate change are not completely understood, an important causal candidate is variation in total solar output. Reported cycles in various climate-proxy data show a tendency to emulate a fundamental harmonic sequence of a basic solar-cycle length (11 years) multiplied by 2(N) (where N equals a positive or negative integer). A simple additive model for total solar-output variations was developed by superimposing a progression of fundamental harmonic cycles with slightly increasing amplitudes. The timeline of the model was calibrated to the Pleistocene/Holocene boundary at 9,000 years before present. The calibrated model was compared with geophysical, archaeological, and historical evidence of warm or cold climates during the Holocene. The evidence of periods of several centuries of cooler climates worldwide called 'little ice ages,' similar to the period anno Domini (A.D.) 1280-1860 and reoccurring approximately every 1,300 years, corresponds well with fluctuations in modeled solar output. A more detailed examination of the climate sensitive history of the last 1,000 years further supports the model. Extrapolation of the model into the future suggests a gradual cooling during the next few centuries with intermittent minor warmups and a return to near little-ice-age conditions within the next 500 years. This cool period then may be followed approximately 1,500 years from now by a return to altithermal conditions similar to the previous Holocene Maximum.

Conference Paper↗

USGS1959

Geology of Glacier National Park and the Flathead Region, Northwestern Montana

This report summarizes available data on two adjacent and partly overlapping regions in northwestern Montana. The first of these is Glacier National Park plus small areas east and west of the park. The second is here called, for convenience, the Flathead region; it embraces the mountains from the southern tip of Glacier Park to latitude 48 deg north and between the Great Plains on the east and Flathead Valley on the west. The fieldwork under the direction of the writer was done in 1948, 1949, 1950, and 1951, with some work in 1952 and 1953. The two regions together include parts of the Swan, Flathead, Livingstone, and Lewis Ranges. They are drained largely by branches of the Flathead River. On the east and north, however, they are penetrated by tributaries of the Missouri River and in addition by streams that flow into Canada. Roads and highways reach the borders of the regions; but there are few roads in the regions and only two highways cross them. The principal economic value of the assemblage of mountains described in the present report is as a collecting ground for snow to furnish the water used in the surrounding lowlands and as a scenic and wildlife recreation area. A few metallic deposits and lignitic coal beds are known, but these have not proved to be important and cannot, as far as can now be judged, be expected to become so. No oil except minor seeps has yet been found, and most parts of the two regions covered do not appear geologically favorable to the presence of oil in commercial quantities. The high, Hungry Horse Dam on which construction was in progress during the fieldwork now floods part of the Flathead region and will greatly influence the future of that region. The rocks range in age from Precambrian to Recent. The thickest units belong to the Belt series of Precambrian age, and special attention was paid to them. As a result, it is clear that at least the upper part of the series shows marked lateral changes within short distances. This fact introduces complexities into stratigraphic correlation and should be remembered wherever the series is studied. The stromatolites, or fossil algae, in the Belt series, although still imperfectly understood, give clues with respect to problems of ecology and stratigraphy. The subdivisions of the Belt series within the areas covered by the present report are, in ascending order, Altyn limestone, Appekunny argillite, Grinnell argillite, Siyeh limestone, and Missoula group. Local subdivisions of the Missoula group are possible in certain areas, and all the units just named are expected to be subdivided when detailed studies are undertaken. In the Glacier National Park and Flathead regions together, it is probable that between 25,000 and 30,000 feet of beds belonging to the Belt series, possibly more, are present. These consist largely of quartzitic argillite, quartzite, and carbonate rocks, mostly dolomitic. Small gabbroic and diabasic intrusive bodies and, at one horizon, basaltic lava are associated with the Belt series. Above the Belt series is a thick sequence of Cambrian, Devonian, and Carboniferous strata, in which limestone is dominant, followed by strata of Jurassic and Cretaceous age, largely limestone and shale and partly of terrestrial origin. Slightly consolidated gravel, sand, and silt of Tertiary age are preserved in some valleys and as erosional remnants on the plains close to the mountain border. Pleistocene and Recent glacial and fluviatile deposits are plentiful in mountain valleys and on the plains east of the mountains. Sufficient crustal movements took place during the latter part of Belt time to produce tension cracks that permitted some intrusion and related extrusion to occur. Broad crustal warping probably took place at intervals during the Paleozoic era, but these successive movements left little record other than the absence of sedimentary rock units that might otherwise have been deposited. The same can be said of much of the Me

Professional Paper↗

USGS1902

Fossil flora of the John Day basin, Oregon

For a number of years I have been gradually accumulating material for a thorough revision of the Tertiary floras of the Pacific slope. Fossil plants are known to occur at numerous points within this area, and their study and identification has already furnished valuable data bearing on the geological history of the region, and when still further exploited it is confidently expected that they will afford more exact data for the use of geologists. This investigation is progressing satisfactorily, and at no distant day it is hoped to have it in form for final publication. From time to time various members of the United States Geological Survey, as well as others not connected with this organization, have sent in small collections of fossil plants for determination. These have been studied and reported upon as fully as the condition of the problem permitted, so that the determinations could be immediately available to geologists, but with the reservation that none of the questions could be fully settled until all known material had been studied and properly correlated. The rich fossil plant deposits in the John Day Basin, as set forth more fully in the historical account which follows, have been known for a period of nearly fifty years, but their study has been carried on in a more or less desultory manner. There has also been considerable confusion as to the horizons whence these plants came. As various species of plants described originally from the John Day region were detected in various other localities in Oregon, and in surrounding areas, as central Washington, western Idaho, and northern California, it became more than ever apparent that a thorough study of all material obtainable from this type area would be necessary before any definite or satisfactory conclusions could be reached. The immediate incentive for this revision was furnished by the receipt of a considerable collection of plants, made by Dr. John C. Merriam in 1900 while he was in charge of an expedition into this region made under the auspices of the University of California. When these plants were submitted to me for study, it was thought possible to present their description, together with a revision of our knowledge of the previously known forms, within a space sufficiently small to permit the publication of the matter as an appendix to a paper on the general geology of the area, then in preparation by Dr. Merriam. But it soon became apparent that this could not be adequately done within the space available, and a short preliminary report was prepared for and published by Dr. Merriam. The results of a complete restudy of all available fossil plant material from the John Day Basin are now presented. I wish to record my great indebtedness to Dr. Merriam, who not only accompanied me at a considerable personal sacrifice on a trip through the region in 1901, but placed unreservedly at my disposal all material bearing in any way on the problem then in the paleontological museum of the University of California. To Dr. Arthur Hollick I am indebted for the loan of all material from the John Day region belonging to Columbia University, and now deposited in the New York Botanical Garden at Bronx Park. This material, together with the rich collections belonging to the United States National Museum, represents practically all now known to have come from the John Day Basin.

Oregon↗

USGS2003

Digital mapping techniques '03 - Workshop proceedings

The Digital Mapping Techniques '03 (DMT'03) workshop was attended by nearly 90 technical experts from 36 agencies, universities, and private companies, including representatives from 22 state geological surveys (see Appendix A). Although the meeting was slightly smaller than DMT'02 it was, considering the budget deficits in nearly all 50 states, very well attended. This workshop was similar in nature to the previous six meetings, held in Lawrence, Kansas (Soller, 1997), in Champaign, Illinois (Soller, 1998), in Madison, Wisconsin (Soller, 1999), in Lexington, Kentucky (Soller, 2000), in Tuscaloosa, Alabama (Soller, 2001), and in Salt Lake City, Utah (Soller, 2002). This year's meeting was hosted by the Pennsylvania Geological Survey, from June 1-4, 2003, on the Millersville University campus in Millersville, Pennsylvania. As in the previous meetings, the objective was to foster informal discussion and exchange of technical information. This objective was well met, as attendees continued to share and exchange knowledge and information, and to renew friendships and collegial work begun at past DMT workshops. All the DMT workshops have been coordinated by the Association of American State Geologists (AASG) and U.S. Geological Survey (USGS) Data Capture Working Group, which was formed in August 1996, to support the AASG and the USGS in their effort to build a National Geologic Map Database (see Soller and Berg, this volume, and <http://ncgmp.usgs.gov/ngmdbproject/ standards/datacapt/>). The Working Group was formed because increased production efficiencies, standardization, and quality of digital map products were needed for the database— and the State and Federal geological surveys—to provide more high-quality digital maps to the public. At the 2003 meeting, oral and poster presentations and special discussion sessions emphasized 1) methods for creating and publishing map products (here, "publishing" includes Web-based release); 2) digital cartographic techniques, 3) analytical GIS techniques; 4) continued development of the National Geologic Map Database; 5) progress toward building and implementing a standard geologic map data model and standard science language, and 6) the need to archive both the published products and the data and observational data that support it.

Open-File Report↗

USGS2015

Evaluating and ranking threats to the long-term persistence of polar bears

The polar bear ( Ursus maritimus ) was listed as a globally threatened species under the U.S. Endangered Species Act (ESA) in 2008, mostly due to the significant threat to their future population viability from rapidly declining Arctic sea ice. A core mandate of the ESA is the development of a recovery plan that identifies steps to maintain viable populations of a listed species. A substantive evaluation of the relative influence of putative threats to population persistence is helpful to recovery planning. Because management actions must often be taken in the face of substantial information gaps, a formalized evaluation hypothesizing potential stressors and their relationships with population persistence can improve identification of relevant conservation actions. To this end, we updated a Bayesian network model previously used to forecast the future status of polar bears worldwide. We used new information on actual and predicted sea ice loss and polar bear responses to evaluate the relative influence of plausible threats and their mitigation through management actions on the persistence of polar bears in four ecoregions. We found that polar bear outcomes worsened over time through the end of the century under both stabilized and unabated greenhouse gas (GHG) emission pathways. Under the unabated pathway (i.e., RCP 8.5), the time it took for polar bear populations in two of four ecoregions to reach a dominant probability of greatly decreased was hastened by about 25 years. Under the stabilized GHG emission pathway (i.e., RCP 4.5), where GHG emissions peak around the year 2040, the polar bear population in the Archipelago Ecoregion of High Arctic Canada never reached a dominant probability of greatly decreased, reinforcing earlier suggestions of this ecoregion’s potential to serve as a long-term refugium. The most influential drivers of adverse polar bear outcomes were declines to overall sea ice conditions and to the marine prey base. Improved sea ice conditions substantively lowered the probability of a decreased or greatly decreased outcome, while an elevated marine prey base was slightly less influential in lowering the probability of a decreased or greatly decreased outcome. Stressors associated with in situ human activities exerted considerably less influence on population outcomes. Reduced mortality from hunting and defense of life and property interactions resulted inmodest declines in the probability of a decreased or greatly decreased population outcome. Minimizing other stressors such as trans-Arctic shipping, oil and gas exploration, and point-source pollution had negligible effects on polar bear outcomes, but that could be attributed to uncertainties in the ecological relevance of those specific stressors. Our findings suggest adverse consequences of loss of sea ice habitat become more pronounced as the summer ice-free period lengthens beyond 4 months, which could occur in portions of the Arctic by the middle of this century under the unabated pathway. The long-term persistence of polar bears may be achieved through ameliorating the loss of sea ice habitat, which will likely require stabilizing CO 2 emissions at or below the ceiling represented by RCP 4.5. Management of other stressors may serve to slow the transition of polar bear populations to progressively worsened outcomes, and improve the prospects of persistence, pending GHG mitigation.

Open-File Report↗

USGS1970

Streamflow from the United States into the Atlantic Ocean during 1931-1960

Streamflow from the United States into the Atlantic Ocean, between the international stream St. Croix River, inclusive, and Cape Sable, Fla., averaged about 355,000 cfs (cubic feet per second) during the 30-year period 1931-60, or roughly 20 percent of the water that, on the average flows out of the conterminous United States. The area drained by streams flowing into the Atlantic Ocean is about 288,000 square miles, including the Canadian part of the St. Croix and Connecticut River basins, or a little less than 10 percent of the area of the conterminous United States. Hence, the average streamflow into the Atlantic Ocean, in terms of cubic feet per second per square mile, is about twice the national average of the flow that leaves the conterminous United States. Flow from about three-fourths of the area draining into the Atlantic Ocean is gaged at streamflow measuring stations of the U.S. Geological Survey. The remaining one-fourth of the drainage area consists mostly of low-lying coastal areas from which the flow was estimated, largely on the basis of nearby gaging stations. Streamflow, in terms of cubic feet per second per square mile, decreases rather progressively from north to south. It averages nearly 2 cfs along the Maine coast, about 1 cfs along the North Carolina coast, and about 0.9 cfs along the Florida coast.

Water Supply Paper↗

USGS2008

Forewarned is forearmed! Progress in development of the U.S. National Early Detection and Rapid Response System for invasive plants: Proposal for a North American early warning system for invasive plants

Currently, a National Early Detection and Rapid Response System (EDRR) for Invasive Plants is being developed in the United States. Conceptually, the system is a coordinated framework of local, state, and national interagency groups that is designed to prevent the establishment and spread of new invasive plants through early detection and reporting of suspected new invaders, identification and vouchering of specimens by cooperating botanists, archiving of confirmed new records in regional and national plant databases, rapid assessment of confirmed new exotic species by federal and state scientists, and rapid control response to new incursions that can be eradicated. A National EDRR Framework is also being developed in Canada, through the work of the federal ministries, as well as provincial invasive species councils. With a functional EDRR communications structure in place in Canada and the U.S., a North American Early Warning System for Invasive Plants can be developed to help publicize information about new and emerging invasive plants across the continent.

Conference Paper↗

USGS2020

Investigation of U.S. Foreign Reliance on Critical Minerals—U.S. Geological Survey technical input document in response to Executive Order No. 13953 Signed September 30, 2020

Over the past few decades (1990–2019), the United States has become reliant on foreign sources to meet domestic demand for a large and growing number of mineral commodities. In combination with recent trends towards progressively concentrated supply of mineral commodities from a limited number of countries, this heightened import reliance may increase the risk to the United States economy and national security. Several factors obscure the true net import reliance of mineral commodities essential to the United States, including indirect trade reliance, embedded trade reliance, and foreign ownership. This report provides a detailed overview of contributions to and trends of these mineral commodity supply risks and provides an outline of the salient factors pertaining to each mineral commodity’s supply chain. It also describes some additional considerations and provides a general framework for evaluating different strategies aimed at reducing net import reliance and supply risk.

Open-File Report↗

USGS2010

Drought Monitoring with VegDRI

Drought strikes somewhere in the United States every year, turning green landscapes brown as precipitation falls below normal levels and water supplies dwindle. Drought is typically a temporary climatic aberration, but it is also an insidious natural hazard. It might last for weeks, months, or years and may have many negative effects. Drought can threaten crops, livestock, and livelihoods, stress wildlife and habitats, and increase wildfire risks and threats to human health. Drought conditions can vary tremendously from place to place and week to week. Accurate drought monitoring is essential to understand a drought's progression and potential effects, and to provide information necessary to support drought mitigation decisions. It is also crucial in light of climate change where droughts could become more frequent, severe, and persistent.

Fact Sheet↗

USGS2002

Historic channel change along Soldier Creek, northeast Kansas

To assess historical channel change along Soldier Creek, northeast Kansas, available information from eight U.S. Geological Survey streamflow-gaging stations was analyzed. At each gaging station, channel change was assessed using channel-bed elevation as the primary indicator variable. Changes in channel-bed elevation were inferred from changes in the stage associated with the mean annual discharge at each station. The variables channel width, channel area, and streamflow velocity were used as additional indicators of change. Results indicated that the most substantial channel changes occurred downstream from Rocky Ford at the Soldier Creek streamflow-gaging stations located near Topeka and Delia. The available evidence indicated that the channelization of Soldier Creek, completed in 1961, was likely the primary cause of the channel changes at these locations. The decreasing base level provided by the Kansas River also may have contributed to the channel changes at these locations. At the Soldier Creek gaging station near Topeka, immediate effects of the channelization included a decrease in channel-bed elevation of about 5 feet and an increase in channel width of about 35 feet. The instability introduced by the channelization caused channel-bed degradation that moved upstream at the rate of about 0.7 to 1.2 miles per year. At the Soldier Creek gaging station near Delia, located about 12 miles upstream from the upstream end of the channelized section, channel-bed degradation began during the 1970s and resulted in a net decrease in channel-bed elevation of about 5 feet by 1999. The available evidence indicated that Soldier Creek at and upstream from Rocky Ford has not been substantially affected by the upstream-progressing channel-bed degradation as of 2001. In this part of the basin other causes of channel change, such as land use and floods, may be relatively more important.

Kansas↗

USGS1995

Physical and hydrologic properties of outcrop samples from a nonwelded to welded tuff transition, Yucca Mountain, Nevada

Quantitative material-property data are needed to describe lateral and vertical spatial variability of physical and hydrologic properties and to model ground-water flow and radionuclide transport at the potential Yucca Mountain nuclear-waste repository site in Nevada. As part of ongoing site characterization studies of Yucca Mountain directed toward this understanding of spatial variability, laboratory measurements of porosity, bull* and particle density, saturated hydraulic conductivity, and sorptivity have been obtained for a set of outcrop samples that form a systematic,two dimensional grid that covers a large exposure of the basal Tiva Canyon Tuff of the Paintbrush Group of Miocene age at Yucca Mountain. The samples form a detailed vertical grid roughly parallel to the transport direction of the parent ash flows, and they exhibit material-property varia- tions in an interval of major lithologic change overlying a potential nuclear-waste repository at Yucca Mountain. The observed changes in hydrologic properties were systematic and consistent with the changes expected for the nonwelded to welded transition at the base of a major ash-flow sequence. Porosity, saturated hydraulic conductivity, and sorptivity decreased upward from the base of the Tiva Canyon Tuff, indicating the progressive compaction of ash- rich volcanic debris and the onset of welding with increased overburden pressure from the accumulating ash-flow sheet. The rate of decrease in the values of these material properties varied with vertical position within the transition interval. In contrast, bulk-density values increased upward, a change that also is consistent with progressive compaction and the onset of welding. Particle-density values remained almost constant throughout the transition interval, probably indicating compositional (chemical) homogeneity.

Water-Resources Investigations Report↗

USGS2006

The 1906 earthquake and a century of progress in understanding earthquakes and their hazards

The 18 April 1906 San Francisco earthquake killed nearly 3000 people and left 225,000 residents homeless. Three days after the earthquake, an eight-person Earthquake Investigation Commission composed of 25 geologists, seismologists, geodesists, biologists and engineers, as well as some 300 others started work under the supervision of Andrew Lawson to collect and document physical phenomena related to the quake . On 31 May 1906, the commission published a preliminary 17-page report titled "The Report of the State Earthquake Investigation Commission". The report included the bulk of the geological and morphological descriptions of the faulting, detailed reports on shaking intensity, as well as an impressive atlas of 40 oversized maps and folios. Nearly 100 years after its publication, the Commission Report remains a model for post-earthquake investigations. Because the diverse data sets were so complete and carefully documented, researchers continue to apply modern analysis techniques to learn from the 1906 earthquake. While the earthquake marked a seminal event in the history of California, it served as impetus for the birth of modern earthquake science in the United States.

GSA Today↗