USGS Science⌕ Search

SEARCH · USGS Science

Results for “Scanning”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 757 records · Page 42Linked to original sources

Borehole P- and S-wave velocity at thirteen stations in Southern California

The U.S. Geological Survey (USGS), as part of a program to acquire seismic velocity data at locations of strong-ground motion in earthquakes (e.g., Gibbs et al., 2000), has investigated thirteen additional sites in the Southern California region. Of the thirteen sites, twelve are in the vicinity of Whittier, California, and one is located in San Bernardino, California. Several deployments of temporary seismographs were made after the Whittier Narrows, California earthquake of 1 October 1987 (Mueller et al., 1988). A deployment, between 2 October and 9 November 1987, was the motivation for selection of six of the drill sites. Temporary portable seismographs at Hoover School (HOO), Lincoln School (LIN), Corps of Engineers Station (NAR), Olive Junior High School (OLV), Santa Anita Golf Course (SAG), and Southwestern Academy (SWA) recorded significant aftershock data. These portable sites, with the exception of Santa Anita Golf Course, were co-sited with strong-motion recorders. Stations at HOO, Lincoln School Whittier (WLB), Saint Paul High School (STP), Alisos Adult School (EXC), Cerritos College Gymnasium (CGM), Cerritos College Physical Science Building (CPS), and Cerritos College Police Building (CPB) were part of an array of digital strong-motion stations deployed from "bedrock" in Whittier to near the deepest part of the Los Angeles basin in Norwalk. Although development and siting of this new array (partially installed at the time of this writing) was generally motivated by the Whittier Narrows earthquake, these new sites (with the exception of HOO) were not part of any Whittier Narrows aftershock deployments. A similar new digital strong-motion site was installed at the San Bernardino Fire Station during the same time frame. Velocity data were obtained to depths of about 90 meters at two sites, 30 meters at seven sites, and 18 to 25 meters at four sites. Lithology data from the analysis of cuttings and samples was obtained from the two 90-meter deep holes and from five of the shallower holes to supplement the velocity interpretation. The two 90-meter boreholes (SB1, CPB) have been instrumented with borehole seismometers for continuous monitoring of earthquake activity (Rogers et al., 1998). No drill samples or cuttings were obtained from the other six sites, but driller's logs were scanned for major changes noted there. The velocity models at those sites were interpreted using only the measured data and major changes in the driller's log as noted above. The sites are shown in Figure 1 and listed in Table 1, which gives references to information regarding the strong-motion data. Several hundred strong-motion records of the main-shock were written by this moderate size earthquake (ML = 5.9), making it important from a scientific and engineering prospective (Brady et al., 1988; Shakal et al., 1988).

California↗

Evaluation of airborne thermal-infrared image data for monitoring aquatic habitats and cultural resources within the Grand Canyon

This study examined thermal-infrared (TIR) image data acquired using the airborne Advanced Thematic Mapper (ATM) sensor in the afternoon of July 25th, 2000 over a portion of the Colorado River corridor to determine the capability of these 100-cm resolution data to address some biologic and cultural resource requirements for GCMRC. The requirements investigated included the mapping of warm backwaters that may serve as fish habitats and the detection (and monitoring) of archaeological structures and natural springs that occur on land. This report reviews the procedure for calibration of the airborne TIR data to obtain surface water temperatures and shows the results for various river reaches within the acquired river corridor. With respect to mapping warm backwater areas, our results show that TIR data need to be acquired with a gain setting that optimizes the range of temperatures found within the water to increase sensitivity of the resulting data to a level of 0.1 °C and to reduce scan-line noise. Data acquired within a two-hour window around maximum solar heating (1:30 PM) is recommended to provide maximum solar heating of the water and to minimize cooling effects of late-afternoon shadows. Ground-truth data within the temperature range of the warm backwaters are necessary for calibration of the TIR data. The ground-truth data need to be collected with good locational accuracy. The derived water-temperature data provide the capability for rapid, wide-area mapping of warm-water fish habitats using a threshold temperature for such habitats. The collected daytime TIR data were ineffective in mapping (detecting) both archaeological structures and natural springs (seeps). The inability of the daytime TIR data to detect archaeological structures is attributed to the low thermal sensitivity (0.3 °C) of the collected data. The detection of subtle thermal differences between geologic materials requires sensitivities of at least 0.1 °C, which can be obtained by most TIR sensors using an appropriate gain setting. Simultaneous data collection for both land and water purposes can be achieved using sensors that collect TIR data in two separate channels, each channel using a gain setting most appropriate for land or water. The detection of archaeological structures and natural water seeps would also be improved by collection of data after sunset, which would require a separate data acquisition from that providing surface water temperature data and therefore additional cost. At this point, the cost for acquiring TIR data is quite high ($620/river-km) compared to the potential benefits of the data, unless reflected-wavelength data are also collected that can satisfy other GCMRC protocol requirements (such as mapping riparian vegetation). This is especially true if multiple data acquisitions are required during the year for temporal analyses of backwater areas. The cost for these data cannot be totally mitigated by its ability to partly replace the need for ground surveys of backwaters because calibration of the TIR data will require some ground-truth data from warm backwater areas (in addition to low-temperature main-stem data). However, the airborne data can provide a product that cannot be approached by ground surveys, that being an instantaneous (2 hour) map of surface water temperature over a 160-km stretch of the Grand Canyon.

Arizona↗

Digital mapping techniques '02, workshop proceedings : May 19-22, 2002, Salt Lake City, Utah

The Digital Mapping Techniques '02 (DMT'02) workshop was attended by 101 technical experts from 43 agencies, universities, and private companies, including representatives from 25 state geological surveys (see Appendix A). This workshop was similar in nature to the previous five meetings, held in Lawrence, Kansas (Soller, 1997), in Champaign, Illinois (Soller, 1998a), in Madison, Wisconsin (Soller, 1999), in Lexington, Kentucky (Soller, 2000), and in Tuscaloosa, Alabama (Soller, 2001). This year's meeting was hosted by the Utah Geological Survey, from May 19 to 22, 2002, on the University of Utah campus in Salt Lake City. As in the previous meetings, the objective was to foster informal discussion and exchange of technical information. When an attendee adopts or modifies a newly learned technique on the basis of discussions at the workshop, the workshop clearly has met that objective. Evidence of learning and cooperation among participating agencies continued to be a highlight of the DMT workshops (see example in Soller, 1998b, and various papers in this volume). All the DMT workshops have been coordinated by the Association of American State Geologists (AASG) and the 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 2002 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) techniques for scanning already published maps and managing and delivering them on the Web; (3) continued development of the National Geologic Map Database; and (4) progress toward building a standard geologic map data model. In addition, special presentations were provided on building a statewide GIS council, incorporating geology as a NSDI Framework layer, and resolving the roles of surveyors and GIS professionals.

Open-File Report↗

Spatial digital database for the geology of the San Pedro River Basin in Cochise, Gila, Graham, Pima, and Pinal Counties, Arizona

This spatial digital database for the geology of the San Pedro River Basin in southeastern Arizona was compiled from three maps by Dickinson (1993, 1998, 2000). Mylar originals of the map sheets were scanned, and the resultant images were rectified to a mathematically-generated set of latitude and longitude registration points. Geologic linework was digitized from the rectified images on screen using ArcView (ver. 3.2), and the resultant shapefiles were converted to ArcInfo (ver. 7.2) coverages. Lines and polygons were then attributed; and the files were merged omtp a single ArcInfo database (quib24k). This digital spatial database is one of many being created by the U.S. Geological Survey as an ongoing effort to provide geologic information in a geographic information system (GIS) for use in spatial analysis. This database can be queried in many ways to produce a variety of geologic maps. Digital base map data files (topography, roads, towns, rivers and lakes, etc.) are not included: they may be obtained from a variety of commercial and government sources. This database is not meant to be used or displayed at any scale larger than 1:24,000 (for example, 1:12,000). The map area is located in southeastern Arizona. This report describes the map units, the methods used to convert the geologic map data into a digital format, and the ArcInfo GIS file structures and relationships; and it explains how to download the digital files from the U.S. Geological Survey public access World Wide Web site on the Internet. See figures 2 and 3 for page-size versions of the map compilation.

Arizona↗

A new method for GPS-based wind speed determinations during airborne volcanic plume measurements

Begun nearly thirty years ago, the measurement of gases in volcanic plumes is today an accepted technique in volcano research. Volcanic plume measurements, whether baseline gas emissions from quiescent volcanoes or more substantial emissions from volcanoes undergoing unrest, provide important information on the amount of gaseous output of a volcano to the atmosphere. Measuring changes in gas emission rates also allows insight into eruptive behavior. Some of the earliest volcanic plume measurements of sulfur dioxide were made using a correlation spectrometer (COSPEC). The COSPEC, developed originally for industrial pollution studies, is an upward-looking optical spectrometer tuned to the ultraviolet absorption wavelength of sulfur dioxide (Millán and Hoff, 1978). In airborne mode, the COSPEC is mounted in a fixed-wing aircraft and flown back and forth just underneath a volcanic plume, perpendicular to the direction of plume travel (Casadevall and others, 1981; Stoiber and others, 1983). Similarly, for plumes close to the ground, the COSPEC can be mounted in an automobile and driven underneath a plume if a suitable road system is available (Elias and others, 1998). The COSPEC can also be mounted on a tripod and used to scan a volcanic plume from a fixed location on the ground, although the effectiveness of this configuration declines with distance from the plume (Kyle and others, 1990). In the 1990’s, newer airborne techniques involving direct sampling of volcanic plumes with infrared spectrometers and electrochemical sensors were developed in order to measure additional gases such as CO2 and H2S (Gerlach and others, 1997; Gerlach and others, 1999; McGee and others, 2001). These methods involve constructing a plume cross-section from several measurement traverses through the plume in a vertical plane. Newer instruments such as open-path Fourier transform infrared (FTIR) spectrometers are now being used to measure the gases in volcanic plumes mostly from fixed locations on the ground. Most FTIR studies to date measure only gas compositions or ratios of gas species (Love and others, 1998; Francis and others, 1998; Horrocks and others, 1999). What all of these methods have in common, however, is the necessity to know plume velocities if accurate gas emission rates are to be calculated. Even open-path FTIR studies done in tandem with a COSPEC require knowledge of plume velocity in order to compute emission rates.

Open-File Report↗

Abstracts of the annual Planetary Geologic Mappers Meeting, June 18-19, 2001, Albuquerque, New Mexico

The annual Planetary Geologic Mappers Meeting serves two purposes. In addition to giving mappers the opportunity to exchange ideas, experiences, victories, and problems with others, presentations are reviewed by the Geologic Mapping Subcommittee (GeMS) to provide input to the Planetary Geology and Geophysics Mapping Program review panel’s consideration of new proposals and progress reports that include mapping tasks. Funded mappers bring both oral presentation materials (slides or viewgraphs) and map products to post for review by GeMS and fellow mappers. Additionally, the annual meetings typically feature optional field trips offering earth analogs and parallels to planetary mapping problems. The 2001 Mappers Meeting, June 18-19, was convened by Tim Parker, Dave Senske, and Ken Tanaka and was hosted by Larry Crumpler and Jayne Aubele of the New Mexico Museum of Natural History and Science in Albuquerque, New Mexico. Oral presentations were given in the Museum’s Honeywell Auditorium, and maps were posted in the Sandia Room. In addition to active mappers, guests included local science teachers who had successfully competed for the right to attend and listen to the reports. It was a unique pleasure for mappers to have the opportunity to interact with and provide information to teachers responding so enthusiastically to the meeting presentation. On Sunday, June 17, Larry and Jayne conducted an optional pre-meeting field trip. The flanks of Rio Grande Rift, east and west of Albuquerque and Valles Caldera north of town presented tectonic, volcanic, and sedimentary examples of the Rift and adjoining areas analogous to observed features on Mars and Venus. The arid but volcanically and tectonically active environment of New Mexico’s rift valley enables focus on features that appear morphologically young and spectacular in satellite images and digital relief models. The theme of the trip was to see what, at orbiter resolution, "obvious" geologic features look like at lander (outcrop) scales. Trips to the top of the rift-flanking mountains (Sandia Peak, 10,600 ft) and the Valles Caldera, as well as various active spring deposits highlighted the day. After welcoming remarks from the host, Larry Crumpler, opening remarks by Tim Parker and Dave Senske and a report on mapping program status by Ken Tanaka, the mappers’ oral presentations began the morning of June 18, with a session on Venus Geologic Mapping. The afternoon continued with an exciting USGS Planetary GIS on the Web (PIGWAD) demonstration and ended with an open discussion of issues in planetary mapping. Posted maps of Venus quadrangles were viewed during the morning break. Tuesday’s Mars Geologic Mapping session began with a pep talk from Tim Parker encouraging mapping community input to the MER landing site selection committee and continued with Steve Saunders describing the potential contribution of Odyssey Mission data to the geologic mapping of Mars. A Mars map poster session was held during the morning break, and the meeting was adjourned mid-afternoon. After the mappers meeting on Tuesday, attendants were treated to a "Field trip to Mars." The Institute of Meteoritics at the University of New Mexico houses an outstanding collection of meteorites, including those that have been identified as originating from Mars. The Institute tour featured examples of most of the different lithologies exhibited by martian meteorites identified to date, as well as some of the analytical tests (scanning electron microscope) they are conducting on specimens from ALH84001. Wednesday, June 20, featured an optional post-meeting field trip to see a travertine quarry and nearby sites of travertine deposition, the Very Large Array near Socorro, and other volcanic features within the Rio Grande Rift.

New Mexico↗

Bathymetry and selected perspective views of 6 reef and coastal areas in Northern Lake Michigan

We apply state of the art laser technology and derivative imagery to map the detailed morphology and of principal lake trout spawning sites on reefs in Northern Lake Michigan and to provide a geologic interpretation. We sought to identify the presence of ideal spawning substrate: shallow, "clean" gravel/cobble substrate, adjacent to deeper water. This study is a pilot collaborative effort with the US Army Corps of Engineers SHOALS (Scanning Hydrographic Operational Airborne Lidar Survey) program. The high-definition maps are integrated with known and developing data on fisheries, as well as limited substrate sedimentologic information and underlying Paleozoic carbonate rocks.

Michigan↗

Digital archives - Thomas M. Bown's Bighorn Basin maps: The suite of forty-four office master copies

This CD-ROM is a digitally scanned suite of master 'locality' maps produced by Dr. Thomas M. Bown. The maps are archived in the US Geological Survey Field Records. The maps feature annual compilations of newly established fossil (nineteen 7.5 degree maps) of central basin data collections. This master suite of forty-four maps represents a considerably broader geographic range within the basin. Additionally, three field seasons of data were compiled into the master suite of maps after the final editing of the Professional Paper. These maps are the culmination of Dr. Bown's Bighorn Basin research as a vertebrate paleontologist for the USGS. Data include Yale, Wyoming, Duke, Michigan and USGS localities. Practical topographic features are also indicated, such as jeep=trail access, new reservoirs, rerouted roadbeds, measured sections, fossil reconnaissance evaluations (G=good, NG=no good and H=hideous), faults, palcosol stages, and occasionally 'camp' vernacular for locality names.

Open-File Report↗

Raster images of geologic maps of Middle Proterozoic Belt strata in parts of Benewah, Bonner, Kootenai and Shoshone Counties, Idaho and Lincoln, Mineral and Sanders Counties, Montana

Geologic maps of the western part of the Belt Basin of western Montana and northern Idaho were converted into digital raster (TIFF image) format to facilitate their manipulation in geographic information systems. The 85-mile x 100-mile map area mostly contains rocks belonging to the lower and middle Belt Supergroup. The area is of interest as these Middle Proterozoic strata contain vein-type lead-zinc-silver deposits in the Coeur d?Alene Mining District in the St. Regis and Revett formations and strata-bound copper-silver deposits, such as the Troy mine, within the Revett Formation. The Prichard Formation is also prospective for strata-bound lead-zinc deposits because equivalent Belt strata in southern British Columbia, Canada host the Sullivan lead-zinc deposit. Map data converted to digital images include 13 geological maps at scales ranging from 1:48,000 to 1:12,000. Geologic map images produced from these maps by color scanning were registered to grid tick coverages in a Universal Transverse Mercator (North American Datum of 1927, zone 11) projection using ArcView Image Analysis. Geo-registering errors vary from 10 ft to 114 ft.

Idaho, Montana↗

Photographs of the Sea floor Offshore of New York and New Jersey

This DVD-ROM contains photographs of the sea floor and sediment texture data collected as part of studies carried out by the U.S. Geological Survey (USGS) in the New York Bight (Figure 1a (PDF format)). The studies were designed to map the sea floor (Butman, 1998, URL: http://pubs.usgs.gov/fs/fs133-98/) and to develop an understanding of the transport and long-term fate of sediments and associated contaminants in the region (Mecray and others, 1999, URL: http://pubs.usgs.gov/fs/fs114-99/). The data were collected on four research cruises carried out between 1996 and 2000 (Appendix I). The images and texture data were collected to provide direct observations of the sea floor geology and to aid in the interpretation of backscatter intensity data obtained from sidescan sonar and multibeam surveys of the sea floor. Preliminary descriptions of the sea floor geology in this region may be found in Schwab and others (2000, URL: http://pubs.usgs.gov/of/of00-295/; 2003), Butman and others (1998, URL: http://pubs.usgs.gov/of/of98-616/.), and Butman and others (2002, URL: http://pubs.usgs.gov/of/of00-503/). Schwab and others (2000 URL: http://pubs.usgs.gov/of/of00-295/; 2003) have identified 11 geologic units in New York Bight (Figure 2 (PDF format)). These units identify areas of active sediment transport, extensive anthropogenic influence on the sea floor, and various geologic units. Butman and others (2003) and Harris and others (in press) present the results of a moored array experiment carried out in the Hudson Shelf Valley to investigate the transport of sediments during winter. Summaries of these and other studies may be found at USGS studies in the New York Bight (URL: http://woodshole.er.usgs.gov/project-pages/newyork/). This DVD-ROM contains digital images of bottom still photographs, images digitized from videos, sediment grain-size analysis results, and short QuickTime movies from video transects. The data are presented in tabular form and in an ESRI (Environmental Systems Research Institute, URL: http://www.esri.com) ArcView project where the image and sample locations may be viewed superimposed on maps showing side-scan sonar and/or multibeam backscatter intensity and bottom topography.

Open-File Report↗

Geology, Geochemistry and Geophysics of Sedimentary Rock-Hosted Au Deposits in P.R. China

This is the second report concerning results of a joint project between the U.S. Geological Survey and the Tianjin Geological Academy to study sedimentary rock-hosted Au deposits in P.R. China. Since the 1980s, Chinese geologists have devoted a large-scale exploration and research effort to the deposits. As a result, there are more than 20 million oz of proven Au reserves in sedimentary rock-hosted Au deposits in P.R. China. Additional estimated and inferred resources are present in over 160 deposits and occurrences, which are undergoing exploration. This makes China second to Nevada in contained ounces of Au in Carlin-type deposits. It is likely that many of the Carlin-type Au ore districts in China, when fully developed, could have resource potential comparable to the multi-1,000-tonne Au resource in northern Nevada. The six chapters of this report describe sedimentary rock-hosted Au deposits that were visited during the project. Chapters 1 and 2 provide an overview of sedimentary rock-hosted Au deposits and Carlin-type Au deposits and also provide a working classification for the sedimentary rock-hosted Au deposits. Chapters 3, 4, and 5 provide descriptions that were compiled from the literature in China in three main areas: the Dian-Qian-Gui, the Qinling fold belt, and Middle-Lower Yangtze River areas. Chapter 6 contains a weights-of-evidence (WofE), GIS-based mineral assessment of sedimentary rock-hosted Au deposits in the Qinling fold belt and Dian-Qian-Gui areas. Appendices contain scanned aeromagnetic (Appendix I) and gravity (Appendix II) geophysical maps of south and central China. Data tables of the deposits (Appendix III) also are available in the first report as an interactive database at http://geopubs.wr.usgs.gov/open-file/of98-466/. Geochemical analysis of ore samples from the deposits visited are contained in Appendix IV.

Open-File Report↗

Spectral reflectance properties (0.4-2.5 um) of secondary Fe-oxide, Fe-hydroxide, and Fe-sulfate-hydrate minerals associated with sulfide-bearing mine waste

Fifteen Fe-oxide, Fe-hydroxide, and Fe-sulphate-hydrate mineral species commonly associated with sulphide bearing mine wastes were characterized by using X-ray powder diffraction and scanning electron microscope methods. Diffuse reflectance spectra of the samples show diagnostic absorption features related to electronic processes involving ferric and/or ferrous iron, and to vibrational processes involving water and hydroxyl ions. Such spectral features enable field and remote sensing based studies of the mineral distributions. Because secondary minerals are sensitive indicators of pH, Eh, relative humidity, and other environmental conditions, spectral mapping of these minerals promises to have important applications to mine waste remediation studies. This report releases digital (ascii) spectra (spectral_data_files.zip) of the fifteen mineral samples to facilitate usage of the data with spectral libraries and spectral analysis software. The spectral data are provided in a two-column format listing wavelength (in micrometers) and reflectance, respectively.

Open-File Report↗

Archive of digital boomer seismic reflection data collected during USGS cruises 94GFP01, 95GFP01, 96GFP01, 97GFP01, and 98GFP02 in Lakes Pontchartrain, Borgne, and Maurepas, Louisiana, 1994-1998

The U.S. Geological Survey, in cooperation with the University of New Orleans, the Lake Pontchartrain Basin Foundation, the National Oceanic and Atmospheric Administration, the Coalition to Restore Coastal Louisiana, the U.S. Army Corps of Engineers, the Environmental Protection Agency, and the University of Georgia, conducted five geophysical surveys of Lakes Pontchartrain, Borgne, and Maurepas in Louisiana from 1994 to 1998. This report serves as an archive of unprocessed digital boomer seismic reflection data, trackline maps, navigation files, observers' logbooks, GIS information, and formal FGDC metadata. In addition, a filtered and gained digital GIF image of each seismic profile is provided. Refer to the Acronyms page for expansion of acronyms and abbreviations used in this report. The archived trace data are in standard Society of Exploration Geophysicists (SEG) SEG-Y format (Barry and others, 1975) and may be downloaded and processed with commercial or public domain software such as Seismic Unix (SU). Examples of SU processing scripts and in-house (USGS) software for viewing SEG-Y headers (Zihlman, 1992) are also provided. Processed profile images, trackline maps, navigation files, and formal metadata may be viewed with a web browser, and scanned handwritten logbooks may be viewed with Adobe Reader. To access the information contained on these discs, open the file 'index.htm' located at the top level of the discs using a web browser. This report also contains hyperlinks to USGS collaborators and other agencies. These links are only accessible if access to the Internet is available while viewing these documents.

Open-File Report↗

Spatial digital database for the geologic map of Oregon

Introduction This report describes and makes available a geologic digital spatial database (orgeo) representing the geologic map of Oregon (Walker and MacLeod, 1991). The original paper publication was printed as a single map sheet at a scale of 1:500,000, accompanied by a second sheet containing map unit descriptions and ancillary data. A digital version of the Walker and MacLeod (1991) map was included in Raines and others (1996). The dataset provided by this open-file report supersedes the earlier published digital version (Raines and others, 1996). This digital spatial database is one of many being created by the U.S. Geological Survey as an ongoing effort to provide geologic information for use in spatial analysis in a geographic information system (GIS). This database can be queried in many ways to produce a variety of geologic maps. This database is not meant to be used or displayed at any scale larger than 1:500,000 (for example, 1:100,000). This report describes the methods used to convert the geologic map data into a digital format, describes the ArcInfo GIS file structures and relationships, and explains how to download the digital files from the U.S. Geological Survey public access World Wide Web site on the Internet. Scanned images of the printed map (Walker and MacLeod, 1991), their correlation of map units, and their explanation of map symbols are also available for download.

Oregon↗

Converting analog interpretive data to digital formats for use in database and GIS applications

There is a growing need by researchers and managers for comprehensive and unified nationwide datasets of scientific data. These datasets must be in a digital format that is easily accessible using database and GIS applications, providing the user with access to a wide variety of current and historical information. Although most data currently being collected by scientists are already in a digital format, there is still a large repository of information in the literature and paper archive. Converting this information into a format accessible by computer applications is typically very difficult and can result in loss of data. However, since scientific data are commonly collected in a repetitious, concise matter (i.e., forms, tables, graphs, etc.), these data can be recovered digitally by using a conversion process that relates the position of an attribute in two-dimensional space to the information that the attribute signifies. For example, if a table contains a certain piece of information in a specific row and column, then the space that the row and column occupies becomes an index of that information. An index key is used to identify the relation between the physical location of the attribute and the information the attribute contains. The conversion process can be achieved rapidly, easily and inexpensively using widely available digitizing and spreadsheet software, and simple programming code. In the geological sciences, sedimentary character is commonly interpreted from geophysical profiles and descriptions of sediment cores. In the field and laboratory, these interpretations were typically transcribed to paper. The information from these paper archives is still relevant and increasingly important to scientists, engineers and managers to understand geologic processes affecting our environment. Direct scanning of this information produces a raster facsimile of the data, which allows it to be linked to the electronic world. But true integration of the content with database and GIS software as point, vector or text information is commonly lost. Sediment core descriptions and interpretation of geophysical profiles are usually portrayed as lines, curves, symbols and text information. They have vertical and horizontal dimensions associated with depth, category, time, or geographic position. These dimensions are displayed in consistent positions, which can be digitized and converted to a digital format, such as a spreadsheet. Once this data is in a digital, tabulated form it can easily be made available to a wide variety of imaging and data manipulation software for compilation and world-wide dissemination.

Open-File Report↗

Binational digital soils map of the Ambos Nogales watershed, southern Arizona and northern Sonora, Mexico

We have prepared a digital map of soil parameters for the international Ambos Nogales watershed to use as input for selected soils-erosion models. The Ambos Nogales watershed in southern Arizona and northern Sonora, Mexico, contains the Nogales wash, a tributary of the Upper Santa Cruz River. The watershed covers an area of 235 km2, just under half of which is in Mexico. Preliminary investigations of potential erosion revealed a discrepancy in soils data and mapping across the United States-Mexican border due to issues including different mapping resolutions, incompatible formatting, and varying nomenclature and classification systems. To prepare a digital soils map appropriate for input to a soils-erosion model, the historical analog soils maps for Nogales, Ariz., were scanned and merged with the larger-scale digital soils data available for Nogales, Sonora, Mexico using a geographic information system.

Arizona, Sonora↗

Summary and preliminary interpretations of USGS cruise A-2-02-HW: Underwater video surveys collected off of Oahu, Molokai, and Maui, Hawaii, June-July 2002

The insular shelves of the southern coasts of the islands of Oahu and Molokai, and the western coast of Maui in the Hawaiian Archipelago were surveyed using ship-towed video between June 26 and July 11, 2002, as part of USGS-CMG cruise A-2-02-HW (Figure 1.1). The goals of the survey were to collect underwater video of the sea floor to: (1) Characterize substrate type and benthic habitat distribution; and (2) Ground-truth recently-acquired data including bathymetric (SHOALS) lidar, side-scan sonar, seismic reflection, and surface texture and grain size. The underwater video also aids in the interpretation and evaluation of Hawaii's benthic habitat maps produced by NOAA and coral reef distribution monitored by the State of Hawaii (Coral Reef Assessment and Monitoring Program - CRAMP; http://cramp.wcc.hawaii.edu/ ). Additional metadata for this cruise is available at: http://walrus.wr.usgs.gov/infobank/a/a202hw/html/a-2-02-hw.meta.html

Hawaii↗

U.S. Geological Survey Scientific Activities in the Exploration of Antarctica: Introduction to Antarctica (Including USGS Field Personnel: 1946-59)

INTRODUCTION Antarctica is the planet's fifth largest continent [13.2 million km2 (5.1 million mi2)]; it contains the Earth's largest (of two) remaining ice sheets; it is considered to be one of the most important scientific laboratories on Earth. This report is the introduction to a series that covers 60 years of U.S. Geological Survey (USGS) scientific activity in Antarctica. It will concentrate primarily on three major topics: 1) a brief chronological record of the historical search, discovery, and exploration of the southern continent by humans; 2) early USGS scientific activities in Antarctica, listing expeditions, projects, people and resulting professional publications for Operation Highjump, 1946-47; Operation Windmill, 1947-48; USS Atka Reconnaissance Cruise, 1954-55; and Operation Deep Freeze I, II, III, and IV, 1955-59, including IGY; 3) significant changes that have occurred in Antarctic exploration and research since World War II will be discussed at the end of this report. Subsequent Open-File Reports will provide a year-by-year documentation of USGS scientific activities and accomplishments in Antarctica beginning with the post-IGY, 1959-60 research team. One Open-File Report is planned to be written for each field-based season. For an example of the series format, see Open-File Reports 2006-1113 (Meunier, 2007a) and 2006-1114 (Meunier, 2007b). This report is a companion document to Open-File Report 2006-1116 (Meunier, 2007c). The USGS mapping and science programs in Antarctica are among the longest continuously funded projects in the United States Antarctic Program (USAP). The 2005-06 field season is the 56th consecutive U.S. expedition in which USGS scientists have been participants, starting in 1946. USGS and the National Science Foundation (NSF) cooperation began with the establishment by NSF of the U.S. Antarctic (Research) Program [USA(R)P] in 1958-59 under Operation Deep Freeze IV (DF IV) and was given the responsibility for the principal coordination and management of all U.S. scientific activities in Antarctica in Deep Freeze 60 (DF 60) (1959-60). Financial support from NSF, mostly in the form of Memorandum of Understandings (MOUs) and Cooperative Agreements, extends back to this period and can be attributed to the need for accurate geologic, geophysical, and topographic base maps of specific field areas or regions where NSF-funded science projects were planned. The epoch of Antarctic exploration during the IGY was driven by science and, in a spirit of peaceful cooperation, the international scientific community wanted to limit military activities on the continent to logistical support (Meunier, 1979 [2007], p. 38). The USGS, a Federal civilian science agency in the Department of the Interior, has, since its founding in 1879, carried out numerous field-based national (and some international) programs in biology, geology, geophysics, hydrology, and mapping. Therefore, the USGS was the obvious choice for these tasks, because it already had a professional staff of experienced mapmakers, scientists, and program managers with the foresight, dedication, and understanding of the need for accurate maps to support the science programs in Antarctica when asked to do so by the U.S. National Academy of Sciences. Public Laws 85-743 and 87-626, signed in August 1958, and in September 1962, respectively, authorized the Secretary, U.S. Department of the Interior, through the USGS, to support mapping and scientific work in Antarctica (Meunier, 1979 [2007], appendix A). Open-File Report 2006-1116 includes scanned facsimiles of postal cachets. It has become an international practice to create postal cachets to commemorate special events and projects in Antarctica. A cachet is defined as a seal or commemorative design printed or stamped on an envelope to mark a philatelic or special event. The inked impression illustrates to the scientist, historian, stamp collector, and general public the multidisciplinary science projects staffed by USGS and collaborating scientists during the field season. Since 1960, philatelic cachets have been created by team members for each USGS field season and, in most cases, these cachets depict the specific geographic areas and field season program objectives. The cachets become a convenient documentation of the people, projects, and geographic places of interest for that year. Because the cachets are representative of USGS activities, each year's cachet is included as a digital facsimile in that year's Open-File Report. In the 1980s, multiple USGS cachets were prepared each year, one for use by the winter team at Amundsen-Scott South Pole Station and the other for the project work areas of the austral summer field season programs.

Open-File Report↗