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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↗

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↗

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↗

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↗

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&rsquo;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↗

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↗

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↗

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↗

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↗

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↗

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↗

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↗

Source and progression of a submarine landslide and tsunami: The 1964 Great Alaska earthquake at Valdez

Like many subduction zone earthquakes, the deadliest aspects of the 1964 M = 9.2 Alaska earthquake were the tsunamis it caused. The worst of these were generated by local submarine landslides induced by the earthquake. These caused high runups, engulfing several coastal towns in Prince William Sound. In this paper, we study one of these cases in detail, the Port Valdez submarine landslide and tsunami. We combine eyewitness reports, preserved film, and careful posttsunami surveys with new geophysical data to inform numerical models for landslide tsunami generation. We review the series of events as recorded at Valdez old town and then determine the corresponding subsurface events that led to the tsunami. We build digital elevation models of part of the pretsunami and posttsunami fjord‐head delta. Comparing them reveals a ~1500 m long region that receded 150 m to the east, which we interpret as the primary delta landslide source. Multibeam imagery and high‐resolution seismic reflection data identify a ~400 m wide chute with hummocky deposits at its terminus, which may define the primary slide path. Using these elements we run hydrodynamic models of the landslide‐driven tsunamis that match observations of current direction, maximum inundation, and wave height at Valdez old town. We speculate that failure conditions at the delta front may have been influenced by manmade changes in drainage patterns as well as the fast retreat of Valdez and other glaciers during the past century.

Alaska↗

Workshop: Western hemisphere network of bird banding programs

Purpose: To promote collaboration among banding programs in the Americas. Introduction: Bird banding and marking provide indispensable tools for ornithological research, management, and conservation of migratory birds on migratory routes, breeding and non-breeding grounds. Many countries and organizations in Latin America and the Caribbean are in the process of developing or have expressed interest in developing national banding schemes and databases to support their research and management programs. Coordination of developing and existing banding programs is essential for effective data management, reporting, archiving and security, and most importantly, for gaining a fuller understanding of migratory bird conservation issues and how the banding data can help. Currently, there is a well established bird-banding program in the U.S.A. and Canada, and programs in other countries are being developed as well. Ornithologists in many Latin American countries and the Caribbean are interested in using banding and marking in their research programs. Many in the ornithological community are interested in establishing banding schemes and some countries have recently initiated independent banding programs. With the number of long term collaborative and international initiatives increasing, the time is ripe to discuss and explore opportunities for international collaboration, coordination, and administration of bird banding programs in the Western Hemisphere. We propose the second ?Western Hemisphere Network of Bird Banding Programs? workshop, in association with the SCSCB, to be an essential step in the progress to strengthen international partnerships and support migratory bird conservation in the Americas and beyond. This will be the second multi-national meeting to promote collaboration among banding programs in the Americas (the first meeting was held in October 8-9, 2006 in La Mancha, Veracruz, Mexico). The Second ?Western Hemisphere Network of Bird Banding Programs? workshop will continue addressing issues surrounding the coordination of an Americas? approach to bird banding and will review in detail the advances made on the first workshop such as, coordination of bands and markers, coordination in recovery reporting, permit issues, data management and data sharing and archiving, data security, training, etc. Workshop Goals: Build on accomplishments of the network?s first workshop (Oct 8-9, 2006). Identify and explore new opportunities for data sharing, data archiving, data access, training, etc. Initiate strategies to support international collaboration and coordination amongst bird banding programs in the Western Hemisphere. Workshop structure: One day workshop of guided discussions. Participants: Representatives of government agencies, program managers and NGOs.

Book chapter↗

Constraints to connecting children with nature--Survey of U.S. Fish and Wildlife Service employees sponsored by the National Conservation Training Center, Division of Education Outreach

The U.S. Fish and Wildlife Service (FWS) names "connecting people with nature" as one of its top six priorities in the online Service Employee Pocket Guide. The National Conservation Training Center (NCTC) took the initiative to identify issues that impede greater progress in addressing constraints to connecting children with nature. The Division of Education Outreach at NCTC formed a working relation with the Policy Analysis and Science Assistance branch of the U.S. Geological Survey to conduct a study on these issues. To meet the objectives of the study, a survey of a sample of FWS employees was conducted. This report includes the description of how the survey was developed and administered, how the data were analyzed, and a discussion of the survey results. The survey was developed based on published literature and incorporated input from two working groups of professionals focused on the issue of connecting children with nature. Although the objective as stated by the FWS is to connect people with nature, the survey primarily focused on connecting children, rather than all people, with nature. The four primary concepts included on the survey were interpretation of how the FWS defined "connection" as part of its mission, perceived success with outreach, constraints to connecting children with nature, and importance of connecting children with nature. The survey was conducted online using KeySurvey&copy; software. The survey was sent to 604 FWS employees. Responses were received from 320 employees. The respondents represented diversity in regions, tenure, wage/grade level, job series, supervisory status, and involvement with education and outreach activities. The key findings of the survey are as follows: * FWS employees believe they as individuals and the agency are successful now and will be more successful in the future in connecting children with nature. * FWS employees believe that there are many outcomes that are relevant to the FWS objective to connect people with the environment. * FWS employees believe that connecting children with nature is important. * Constraints to connecting children with nature exist but are not perceived by respondents to be severe. * The constraints of greatest concern are practical issues, competition from technology, funding issues and staffing issues.

Open-File Report↗

Drake Peak — A structurally complex rhyolite center in southeastern Oregon

The Drake Peak volcanic center of middle Miocene age, located about 25 km northeast of Lakeview, Oreg., is a structurally complex eruptive center that resulted from several episodes of intrusion and extrusion of rhyolite. Two thousand meters of andesite and basalt flows, lahars, and volcaniclastic rocks of late Eocene age, and of basaltic andesite, tuff, and flood basalts of Eocene to middle Miocene age were structurally domed by the piston-like intrusion of a large body of rhyolite. The eruption of rhyolite flows at 14.3±2 million years followed the structural doming, and upper Miocene tuffs and basalt flows lapped against the dome and the rhyolite. A felsitic rhyolite ring intrusion 3 km in diameter, emplaced during the doming, is now exposed in the deeply eroded core of the dome. The rhyolites range in Si02 content from 69 to 76 percent and are peraluminous. The nonporphyritic ring intrusion is more silicic than the flows erupted later, which contain up to 23 percent phenocrysts of plagioclase, hypersthene, biotite, clinopyroxene, and quartz. The progressive depletion of Mg, Ca, Sr, Fe, Ti, and Al and the enrichment in silicon and rubidium are compatible with the generation of the observed rhyolite types by tapping a compositionally zoned magma chamber.

Oregon↗

The Program for Regional and International Shorebird Monitoring (PRISM)

This report describes the "Program for Regional and International Shorebird Monitoring" (PRISM). PRISM is being implemented by a Canada-United States Shorebird Monitoring and Assessment Committee formed in 2001 by the Canadian Shorebird Working Group and the U.S. Shorebird Council. PRISM provides a single blueprint for implementing the shorebird conservation plans recently completed in Canada and the United States. The goals of PRISM are to (1) estimate the size of breeding population of 74 shorebird taxa in North America; (2) describe the distribution, abundance, and habitat relationships for each of these taxa; (3) monitor trends in shorebird population size; (4) monitor shorebird numbers at stopover locations, and; (5) assist local managers in meeting their shorebird conservation goals. PRISM has four main components: arctic and boreal breeding surveys, temperate breeding surveys, temperate non-breeding surveys, and neotropical surveys. Progress on, and action items for, each major component are described. The more important major tasks for immediate action are carrying out the northern surveys, conducting regional analyses to design the program of migration counts, and evaluating aerial photographic surveys for migration and winter counts.

General Technical Report↗

Longitudinal water-temperature profiles in Mill Creek, Mason County, Washington

In streams supporting Pacific salmon ( Oncorhynchus spp.) within the southern Puget Lowland, high water temperatures during late summer are a primary water-quality concern. The metabolic rates of fish and other ectothermic (in other words, cold-blooded) species are regulated by water temperature; salmon and other cold-water fish have specific thermal tolerances outside of which they are susceptible to infection, disease, increased predation, and decreased reproductive success. Mill and Gosnell Creeks, which collectively drain a 30-square mile area of the Puget Lowland in Mason County, Washington, support several species of anadromous salmonids. Whereas previous studies documented relatively cool water temperatures in Gosnell Creek, which drains the watershed upstream from Lake Isabella, water temperatures in Mill Creek, which heads at the outlet of Lake Isabella, regularly exceed thermal tolerances for cold-water fish. The occurrence and distribution of cold-water anomalies in less-than-ambient water temperatures in Mill Creek, however, have not been assessed. In this report, we present spatially and temporally continuous measurements of near-streambed water temperature measured using fiber-optic distributed temperature sensing for three reaches of Mill Creek during August–September 2020 when the water temperatures of streams in western Washington were near their annual maximum. Water temperature was collected every hour and averaged spatially over 1.015-meter sections of the fiber-optic cable deployed at the streambed of Mill Creek. The lengths of the fiber-optic cables deployed in Reaches A, B, and C were 883, 270, and 1,014 meters, respectively. Daily maximum water temperature and daily temperature variability, as measured by standard deviation of water temperature during the deployment, progressively decreased downstream as distance from Lake Isabella increased. However, no abrupt decreases in daily maximum or standard deviation of water temperature were detected in longitudinal temperature profiles of any of the three reaches. Collectively, these results suggest that warm water discharged from Lake Isabella was progressively buffered downstream as it equilibrated with downstream heat fluxes mediated by physical processes including riparian shading and diffuse groundwater input. Although parts of the surveyed reaches associated with deep pools were cooler than other locations, no large (less than 2 °C) water-temperature anomalies characteristic of discrete sources of cold groundwater or surface-water inputs were measured in any of the three surveyed reaches.

Washington↗