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This Open-File Report is released as a digital map database. It includes PostScript plot files that contain images of the map sheets; the images also contain a brief explanation describing the geology and physiography of the study area. The digital map database is a compilation of newly published 10-m digital-elevation-model (DEM) data for western Oregon and represents the physiography of the Willamette Valley.
The magnetic anomaly data open-filed in this report represent part of a much larger data set covering most of the conterminous United States. The anomaly map consists of 10 sheets covering an area in the northwestern United States. These were prepared primarily from existing aeromagnetic data, and secondarily from ground data, the latter located primarily in North Dakota and South Dakota.
The purpose was to identify potential cryptocrystalline material sources for tools used by indigenous people of the northern Nevada portion of the Great Basin. Cryptocrystalline occurrence data combed from the U.S. Geological Survey's Mineral Resources Data System (MRDS, 1995) were combined with sites described in Nevada rockhound guides and entered into a geographic information system (GIS). The map area encompasses northern Nevada (fig.1). This open-file report describes the methods used to convert cryptocrystalline occurrence data into a digital format, documents the file structures, and explains how to download the digital files from the U.S. Geological Survey's World Wide Web site. Uses of the spatial dataset include, but are not limited to, natural and cultural resource management, interdisciplinary activities, recreational rockhounding, and gold exploration. It is important to note that the accuracy of the spatial data varies widely, and for some purposes, field checks are advised.
The digital magnetic anomaly database and map for the North American continent is the result of a joint effort by the Geological Survey of Canada (GSC), U. S. Geological Survey (USGS), and Consejo de Recursos Minerales of Mexico (CRM). This integrated, readily accessible, modern digital database of magnetic anomaly data is a powerful tool for further evaluation of the structure, geologic processes, and tectonic evolution of the continent and may also be used to help resolve societal and scientific issues that span national boundaries. The North American magnetic anomaly map derived from the digital database provides a comprehensive magnetic view of continental-scale trends not available in individual data sets, helps link widely separated areas of outcrop, and unifies disparate geologic studies. This open-file report presents three unique, gridded data sets used to make the magnetic anomaly map of North America. Subsets of these three grids that span only the United States were also created, giving a total of six grids. Details on the data processing and compilation procedures used to produce the grids are described in the booklet that accompanies the North American magnetic anomaly map. All three grids have 1-km spacing and are projected to the DNAG projection (spherical transverse mercator, central meridian of 100 o W, base latitude of 0o, scale factor of 0.926 and Earth radius of 6,371,204 m.) More details are given in the metadata files that accompany the gridded data files. These grids are presented in Geosoft binary grid format, with two files describing each of the six grids (suffixes .grd and .gi). This format can be easily converted to numerous other formats using the free conversion software offered by this company at http://www.geosoft.com/. The first grids (NAmag_origmrg.grd and USmag_origmrg.grd) show the magnetic field at 305 m. above terrain. For the second grids (NAmag_hp500.grd and USmag_hp500.grd) we removed long-wavelength anomalies (500 km and greater) from the first grid. This grid was used for the published map. Although the North American merged grid represents a significant upgrade to older compilations, the existing patchwork of surveys is inherently unable to accurately represent anomalies with long (greater than roughly 150 km) wavelengths, particularly in the US and Canada (U.S. Magnetic-Anomaly Data Set Task Group, 1994). The lack of information about long wavelength anomalies is primarily related to datum shifts between merged surveys, caused by data acquisition at widely different times and by differences in merging procedures. Therefore, we removed anomalies with wavelengths greater than 500 km from the merged grid to reduce the effects caused by the spurious long wavelengths but still maintain the continuity of anomalies. The correction was accomplished by transforming the merged grid to the frequency domain, filtering the transformed data with a long-wavelength cutoff at 500 km, and subtracting the long-wavelength data grid from the merged grid. In addition to the 500-km high pass filter, an equivalent source method, based on long-wavelength characterization using satellite data (CHAMP satellite anomalies, Maus and others, 2002), was also used to correct for spurious shifts in the original magnetic anomaly grid (Ravat and others, 2002). These results are presented in the third grids (NAmag_CM.grd and USmag_CM.grd), in which the wavelengths longer than 500 km have been replaced by downward-continued satellite data. The steps used to create the third long-wavelength-corrected grid are: 0. The North American 1-km merged grid was decimated to 5 km. 1. This 5-km grid was converted to a 0.05 degree grid and was low-pass filtered using a Gaussian filter with a 500-km cutoff, then decimated to 1 degree. 2. A joint inversion of this 1-degree low-pass aeromagnetic grid and satellite data, with the aeromagnetic data weighted very low, was used to produce a stabilized downward continuation of the satellite data. 3. The inverted data were interpolated to 0.05 degrees and again low-pass filtered using the same Gaussian 500-km filter to remove short-wavelength artifacts. 4. The low-pass grid from step 1 was subtracted from the original 0.05-degree aeromagnetic grid to create a 500-km high-pass aeromagnetic grid. This grid was added to the low-pass inverted grid from step 3 to get a corrected 0.05-degree aeromagnetic grid. 5. The corrected 0.05-degree aeromagnetic grid was projected to the DNAG projection and regridded to 5 km. This was subtracted from the decimated 5-km aeromagnetic grid to generate a 5-km correction grid. A matched filter was used to remove short-wavelength artifacts resulting from the projection and regridding process. 6. The resulting 5-km correction grid was regridded to the original 1-km grid and subtracted from the original 1-km aeromagnetic grid to generate the final 1-km corrected aeromagnetic grid. The six grids described in this report are available for download. Two metadata files, one for the North American grids and one for the United States grids, are also included with the gridded data.
This report summarizes a three-year study of aeolian sedimentary processes in the Colorado River corridor, Grand Canyon, Arizona, and discusses the relevance of those processes to the preservation of archaeological sites. Findings are based upon detailed sedimentary and geomorphic investigations conducted in three areas of the river corridor, continuous measurements of wind, precipitation, and aeolian sediment transport at six locations for up to 26 months, short-term field study at 35 other sites, examination of historical aerial photographs, and review of data collected and analyzed by previous studies. Detailed results of this study, which involved collaboration with scientists at the Grand Canyon Monitoring and Research Center, National Park Service, Northern Arizona University, the Hopi Tribe, and GeoArch, Inc., have been published previously in topical USGS Open-File Reports (Draut and Rubin, 2005, 2006), a USGS Scientific Investigations Report (Draut and others, 2005), and will be discussed in two forthcoming journal articles. This report serves as an overview of the results and contains new conclusions regarding aeolian sedimentary processes in the Colorado River Ecosystem and their relevance to many archaeological sites.
Plague is an acute and often fatal zoonotic disease caused by the bacterium Yersinia pestis . Y. pestis mainly cycles between small mammals and their fleas; however, it has the potential to infect humans and frequently causes fatalities if left untreated. It is often considered a disease of the past; however, since the late 1800s, plagueis geographic range has expanded greatly, posing new threats in previously unaffected regions of the world, including the Western United States. A literature search was conducted using Internet resources and databases. The keywords chosen for the searches included plague, Yersinia pestis , management, control, wildlife, prairie dogs, fleas, North America, and mammals. Keywords were used alone or in combination with the other terms. Although this search pertains mostly to North America, citations were included from the international research community, as well. Databases and search engines used included Google ( http://www.google.com ), Google Scholar ( http://scholar.google.com ), SciVerse Scopus ( http://www.scopus.com ), ISI Web of Knowledge ( http://apps.isiknowledge.com ), and the USGS Library's Digital Desktop ( http://library.usgs.gov ). The literature-cited sections of manuscripts obtained from keyword searches were cross-referenced to identify additional citations or gray literature that was missed by the Internet search engines. This Open-File Report, published as an Internet-accessible bibliography, is intended to be periodically updated with new citations or older references that may have been missed during this compilation. Hence, the authors would be grateful to receive notice of any new or old papers that the audience (users) think need to be included.
This open-file report consists of two colored 35-mm photographic slides. Slide 1 is a photograph of a hand-colored copy of the geologic map of the Dillon 1' x 2' quadrangle. Scale of original 1:250,00. Slide 2 is a brief explanation of the map units shown on slide 1.
OVERVIEW: This report contains water-quality and sediment-quality data from samples collected in the Yukon River Basin from March through September during the 2005 water year (WY). Samples were collected throughout the year at five stations in the basin (three on the main stem Yukon River, one each on the Tanana and Porcupine Rivers). A broad range of physical, chemical, and biological analyses are presented. This is the final report in a series of five USGS Open-File Reports spanning five WYs, from October 2000 through September 2005. The previous four reports are listed in the references (Schuster, 2003, 2005a, 2005b, 2006). Water-quality and sediment-quality data from samples collected on the Yukon River and selected major tributaries in Alaska for synoptic studies during WYs 2002-03 are published in Dornblaser and Halm (2006).
Rare earth elements (REEs) are critical mineral commodities for the United States. In response to a need for information on potential domestic sources of REEs in mineral deposits, the U.S. Geological Survey (USGS) identified broad focus areas throughout the conterminous United States and Alaska as a guide for selecting new geoscience research areas. This study was done to support the USGS Earth Mapping Resources Initiative (Earth MRI). Focus areas are identified in four regions of the United States (Alaska, West, Central, and East) by mineral deposit type. The areas are described in a companion USGS data release that consists of a map in a geographic information system and accompanying tables that document the rationale for each focus area (C.L. Dicken and others, 2019, https://doi.org/10.5066/P95CHIL0 ). This open-file report describes the methodology that was used to identify focus areas and determine new data acquisition needs. Deposit types that are likely to be of interest for future exploration and development of domestic nonfuel REE resources include deposits associated with carbonatites and peralkaline rocks, iron oxide-apatite deposits, monazite-bearing placers, and REE-enriched phosphorites.
The San Andreas fault is the longest fault in California and one of the longest strikeslip faults in the world, yet little is known about the aftershocks following the most recent great event on the San Andreas, the M 7.8 San Francisco earthquake, on 18 April 1906. This open-file report is a compilation of first-hand accounts (felt reports) describing aftershocks and triggered events of the 1906 earthquake, for the first twenty months of the aftershock sequence (through December 1907). The report includes a chronological catalog. For the larger events, Modified Mercalli intensities (MMIs) have been assigned based on the descriptions judged to be the most reliable.
This U.S. Geological Survey Open-File Report provides information from assessments of Earth observation sensors completed by the U.S. Geological Survey Earth Resources Observation and Science Cal/Val Center of Excellence. These reports are provided as independent measures of basic system performance by the Earth Resources Observation and Science Cal/Val Center of Excellence team by completing the geometric, radiometric, and spatial characterization. The results of these assessments are a snapshot in time.
Introduction: This map and associated digital databases are the result of a compilation and reinterpretation of published and unpublished 1:250,000- and limited 1:125,000- and 1:63,360-scale mapping. The map area covers approximately 416,000 sq km (134,000 sq mi) and encompasses 25 1:250,000-scale quadrangles in central Alaska. The compilation was done as part of the U.S. Geological Survey National Surveys and Analysis project, whose goal is nationwide assemble geologic, geochemical, geophysical, and other data. This map is an early product of an effort that will eventually encompass all of Alaska, and is the result of an agreement with the Alaska Department of Natural Resources, Division of Oil And Gas, to provide data on interior basins in Alaska. A paper version of the three map sheets has been published as USGS Open-File Report 98-133. Two geophysical maps that cover the identical area have been published earlier: 'Bouguer gravity map of Interior Alaska' (Meyer and others, 1996); and 'Merged aeromagnetic map of Interior Alaska' (Meyer and Saltus, 1995). These two publications are supplied in the 'geophys' directory of this report.
The northern South Carolina coast is a heavily developed region that supports a thriving tourism industry, large local populations and extensive infrastructure (Figure 1). The economic stability of the region is closely tied to the health of its beaches: primarily in providing support for local tourism and protection from storm events. Despite relatively low long-term shoreline erosion rates, and the implied stability of the beaches, the economic impact of storm events to coastal communities has been costly. For example, Hurricane Hugo made landfall on the central South Carolina coast in 1989. High winds and storm surge inflicted roughly $6 billion in property loss and damages, and Hugo remains the costliest storm event in South Carolina history. Localized erosion, commonly occurring around tidal inlets and erosion "hot spots", has also proved costly. Construction and maintenance of hard structures and beach nourishment, designed to mitigate the effects of erosion, have become annual or multi-annual expenditures. Providing a better understanding of the physical processes controlling coastal erosion and shoreline change will allow for more effective management of coastal resources. In 1999, the U.S. Geological Survey (USGS), in partnership with the South Carolina Sea Grant Consortium (SCSGC), began a study to investigate inner continental shelf and shoreface processes. The objectives of the USGS/SCSGC cooperative program are: 1) to provide a regional synthesis of the shallow geologic framework underlying the shoreface and inner continental shelf, and to define its role in coastal evolution and modern beach behavior; 2) to identify and model the physical processes affecting coastal ocean circulation and sediment transport, and to define their role in shaping the modern shoreline; and 3) to identify sediment sources and transport pathways in order to develop a regional sediment budget. This report contains the geospatial data used to define the geologic framework offshore of the northern South Carolina coast. The digital data presented herein accompany USGS Open-File Reports OFR 2004-1013 and OFR 2005-1345, describing the stratigraphic framework and modern sediment distribution within Long Bay, respectively. Direct on-line links to these publications are available within 'References' on the navigation bar to the left. Additional links to other publications and web sites are also available.
The data reported here was collected during the 1982-1988 mineral resource assessment of the Port Moller and adjacent quadrangles (see Wilson and others, 1996). Analytical data for virtually all of the samples reported here has been previously published in a series of U.S.G.S. Open-File reports, including Angeloni and others (1985), Arbogast and others (1987), and Wilson and others (1987). Induction-coupled plasma (ICP) data is reported here for the first time on stream sediment samples resulting from analyses conducted by S.E. Church in the early 1990's. We have selected a subset of the Port Moller assessment data for inclusion in this report.
Investigation of the ground-water resources of Santa Barbara County was continued during 1962 by the U. S. Geological Survey in cooperation with the Santa Barbara County Water Agency. Monthly water-level measurements were made in 201 wells, in 9 of which automatic water-level recorders were operated. Earlier measurements, covering the period 1941 through 1955, have been published in U.S. Geological Survey Water-Supply Papers (19)43-1957); those for 1:56 through 1961 have been released locally in duplicated form (Muir and Merritt, 1957; Evenson 1950; Miller, 1959; Muir, Merritt, and Miller, 1960; Merritt, 1961; and Muir, 1962). LaRocque, Jr., and others (1950) contains tabulated descriptions of 2,246 wells in existence in 1942 in the several ground-water basins of the county. The same publication also contains many water-level measurements made prior to 1942 by the city of Santa Barbara, Santa Maria Valley Water Conservation District, San Joaquin Power Division of the Pacific Gas and Electric Co., Union Sugar Co., Union Oil Co., and other organizations and individuals. Comprehensive reports on the geology and and ground-water resources of the Santa. Ynez River basin (Upson and Thomasson, 1951, and Wilson, 1959), the south-coast basin (Upson, 1951), the Santa Maria Valley area (Worts, 1951), and the Cuyvma Valley (Upson and Worts, 1951) have been published as Water-Supply Papers 1107, 1467, 1108, 1000, and 1110-B, respectively. A similar report on the San Antonio Creek Valley is in preparation. A report on stream runoff and ground-water storage capacity of the Santa Ynez River Valley (Troxell and Wilson, 1952) was released to the open file in October 1952. In addition to the water-level measurements made by the Geological Survey in 1962, measurements made by the Santa Maria Valley Water Conservation District are included in this report. Not included in this report are miscellaneous measurements made by the U.S. Bureau of Reclamation in wells along the middle reach of the Santa Ynez River between Cachuma Dam and Rucker Crossing.
The Cheyenne River System in western South Dakota has been impacted by the discharge of about 100 million metric tons of gold-mill tailings to Whitewood Creek near Lead, South Dakota. In April 1985, the U.S. Geological Survey initiated an extensive series of research studies to investigate the magnitude of the impact and to define important processes acting on the contaminated sediments present in the system. The report presents all data collected during the 1987 and 1988 water years for these research studies. Some of the data included have been published previously. Data collected in the 1985 and 1986 water years have been published in a companion report (U.S. Geological Survey Open-File Report 88-484). Hydrologic, geochemical, and biologic data are available for sites on Whitewood Creek, and the Belle Fourche and Cheyenne Rivers. Data complexity varies from routine discharge and water-quality to very complex energy-dispersive x-ray analysis. Methods for sample collection, handling and preservation, and laboratory analysis are also presented. No interpretations or complex statistical summaries are included. (See also W89-08390) (USGS)
The geologic framework and the hydrologic situation in Long Island are periodically reviewed by the U.S. Geological Survey as new knowledge is obtained from current investigations. This work is done through cooperative programs with Nassau and Suffolk County agencies and the New York State Department of Environmental Conservation. A unique opportunity to update many of the hydrogeologic maps occurred when the Geological Survey's Mineola, N.Y., office participated in the New England River Basins Commission's "Long Island Sound Study." This map, one of a series of open-file maps showing the updated information, was compiled from data obtained from G. E. Kimmel (written commun., July 1972) and Jensen and Soren (in press). Comparison of the March 1971 data with similar data for March 1970 (Kimmel, 1970) shows virtually no change in water levels on Long Island during the 12 month period, except for a slight decline in levels in central Suffolk County.
Investigation of the ground-water resources of Santa Barbara County was continued during 1961 by the U. S. Geological Survey in cooperation with the Santa Barbara County Water Agency. Monthly water-level measurements were made in 190 wells, in 9 of which automatic water-level recorders were operated. Earlier measurements, covering the period 1941 through 1955, have been published in U. S. Geological Survey Water-Supply Papers (1943-1957); those for 1956 through 1960 have been released locally in duplicated form (Muir and Merritt, 1957; Evenson, 1958; Miller, 1959; Muir, Merritt, and Miller, 1960; and Merritt, 1961). LaRocque, Jr., and others (1950) contains tabulated descriptions of 2,246 wells in existence in 1942 in the several ground-water basins of the county. The same publication also contains many water-level measurements made prior to 1942 by the city of Santa Barbara, Santa Maria Valley Water Conservation District, San Joaquin Power Division of the Pacific Gas and Electric Co., Union Sugar Co., Union Oil Co., and other organizations and individuals. Comprehensive reports on the geology and ground-water resources of the Santa Ynez River basin (Upson and Thomasson, 1951, and Wilson, 1959), the south-coast basins (Upson, 1951), the Santa Maria Valley area (Worts, 1951), and the Cuyama Valley (Upson and Worts, 1951) have been published as Water-Supply Papers 1107, 1467, 1108, 1000, and 1110-B, respectively. A similar report on the San Antonio Creek Valley is in preparation. A report on stream runoff and ground-water storage capacity of the Santa Ynez River valley (Troxell and Wilson, 1952) was released to the open file on October 1952. In addition to the water-level measurements made by the Geological Survey in 1961, measurements made by the Santa Maria Valley Water Conservation District are included in this report. Not included in this report are miscellaneous measurements made by the U. S. Bureau of Reclamation in wells along the middle reach of the Santa Ynez River between Cachuma Dam and Rucker Crossing.