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USGS2008

L5 TM radiometric recalibration procedure using the internal calibration trends from the NLAPS trending database

From the Landsat program's inception in 1972 to the present, the earth science user community has benefited from a historical record of remotely sensed data. The multispectral data from the Landsat 5 (L5) Thematic Mapper (TM) sensor provide the backbone for this extensive archive. Historically, the radiometric calibration procedure for this imagery used the instrument's response to the Internal Calibrator (IC) on a scene-by-scene basis to determine the gain and offset for each detector. The IC system degraded with time causing radiometric calibration errors up to 20 percent. In May 2003 the National Landsat Archive Production System (NLAPS) was updated to use a gain model rather than the scene acquisition specific IC gains to calibrate TM data processed in the United States. Further modification of the gain model was performed in 2007. L5 TM data that were processed using IC prior to the calibration update do not benefit from the recent calibration revisions. A procedure has been developed to give users the ability to recalibrate their existing Level-1 products. The best recalibration results are obtained if the work order report that was originally included in the standard data product delivery is available. However, many users may not have the original work order report. In such cases, the IC gain look-up table that was generated using the radiometric gain trends recorded in the NLAPS database can be used for recalibration. This paper discusses the procedure to recalibrate L5 TM data when the work order report originally used in processing is not available. A companion paper discusses the generation of the NLAPS IC gain and bias look-up tables required to perform the recalibration.

Conference Paper↗

USGS2024

Developing and implementing an International Macroseismic Scale (IMS) for earthquake engineering, earthquake science, and rapid damage assessment

Executive Summary Macroseismic observations and analysis connect our collective seismological past with the present and the present to the future by facilitating hazard estimates and communicating the effects of ground shaking to a wide variety of audiences across the ages. Invaluable ground shaking and building damage information is gained through standardized, systematic approaches for assigning intensities and, importantly, sharing and archiving those assignments in a reproducible form. The applications for these assignments are far reaching. Traditional macroseismic surveys provide vital constraints on critical aspects of earthquakes and their effects on society, whereas internet-based macroseismic datasets are extremely valuable for real-time earthquake situational awareness, and they contribute to later engineering loss and risk analyses. These important applications of macroseismic observations would be helped by revisiting traditional macroseismic surveys for modern environments, standardizing internet-based collection strategies, and ensuring compatibility between traditional and internet-based approaches of macroseismic data collection. Even with best practices, we have identified several limitations with modern macroseismic data collection approaches, particularly from the U.S. Geological Survey's perspective. First, whereas crowdsourced, internet-based intensities such as “Did You Feel It?” are robust and definitive for lower intensities, they are poorly defined above intensity VII, where damage observations may require expert knowledge of each building’s structural system. Second, in the United States, we use the Modified Mercalli Intensity (MMI) Scale, which is consistent with—yet inferior to—the more recently developed European Macroseismic Scale (EMS–98; Grünthal and others, 1998). Similarly, New Zealand uses the New Zealand MMI Scale (Dowrick and others, 2008), which lacks detail on how to assign intensities above MMI VIII. The EMS–98 fundamentally advanced the science of macroseismic intensity assignment by requiring quantitative assessments at each location through consistent application on statistical ranges of well-defined damage grades to building-specific vulnerability classes. Lastly, the United States and New Zealand no longer have professionals dedicated to conducting traditional macroseismic field surveys, so a strategy is needed for allowing postearthquake building inspectors and insurance loss assessors to contribute to intensity assignments. The goals of our International Macroseismic Scale workshop were thus twofold. First, harmonize the MMI Scale with EMS–98 for the United States and New Zealand—which share several similar building types—by considering those structures and associated damage grades that are not well represented in the current EMS–98 building vulnerability class table. Second, begin to formalize the process of augmenting EMS–98 with new regional building classes and damage grades toward the development of a macroseismic scale that can be used globally, beyond the United States and New Zealand. Such an effort necessarily requires reviewing and expanding the original EMS–98 explanatory documents and consideration of any required revisions. We can build on the shoulders of giants in that a few of the original EMS–98 developers and experts participated in and were integral to our workshop. Their background and guidance were key in moving forward toward an international scale. We agreed that additional building vulnerability classes, damage grades, and written and pictorial descriptions are necessary and ideally accompanied by a detailed paper trail for other nations to follow. If we can improve the macroseismic assignment process in both nations, we can also aim to refine the process of collecting postearthquake impact data, a boon to many engineering and financial concerns. The benefits of a truly International Macroseismic Scale are considerable for both the engineering and seismology communities. A modern macroseismic scale requires more deliberate archival damage data collection, motivating more consistent and accessible postevent datasets that would have applications beyond the specific event. Applying field-collected building damage data toward macroseismic assignments would allow for increased coordination between engineering reconnaissance teams and local inspectors in collecting such data for official purposes. In addition, rapid and consistent intensity assignments globally would enable more accurate ShakeMaps—and thus improved earthquake engineering and geotechnical forensics, loss and risk estimates, and correlations between macroseismic intensity and ground motion parameters. A brief summary of the Powell Center IMS workshop was published by Wald and others (2023) in the magazine Eos. This Open-File Report describes the workshop, its discussions, and its outcomes in detail. In summarizing the workshop, we have added important background material and reflections for proper context.

Open-File Report↗

USGS2008

Proceedings of a USGS Workshop on Facing Tomorrow's Challenges Along the U.S.-Mexico Border - Monitoring, Modeling, and Forecasting Change Within the Arizona-Sonora Transboundary Watersheds

INTRODUCTION TO THE WORKSHOP PROCEEDINGS Competition for water resources, habitats, and urban areas in the Borderlands has become an international concern. In the United States, Department of Interior Bureaus, Native American Tribes, and other State and Federal partners rely on the U.S. Geological Survey (USGS) to provide unbiased science and leadership in the Borderlands region. Consequently, the USGS hosted a workshop, ?Facing Tomorrow?s Challenges along the U.S.-Mexico Border,? on March 20?22, 2007, in Tucson, Ariz., focused specifically on monitoring, modeling, and forecasting change within the Arizona-Sonora Transboundary Watersheds

Circular↗

USGS1974

Geology of the Juazohn Quadrangle, Liberia

As part of a program undertaken cooperatively by the Liberian Geological Survey (LGS) and the U. S. Geological Survey (USGS), under the sponsorship of the Government of Liberia and the Agency for International Development, U. S. Department of State, Liberia was mapped by geologic and geophysical methods during the period 1965 to 1972. The resulting geologic and geophysical maps are published in ten folios, each covering one quadrangle (see index map). The Juazohn quadrangle was systematically mapped by the author from December 1970 to June 1972. Field data provided by private companies and other members of the LGS-USGS project were used in map compilation, and are hereby acknowledged.

Juazohn Quadrangle↗

USGS1978

Appraisal of uncontrolled flowing artesian wells in Florida

An estimated 15,000 uncontrolled flowing wells, many discharging water of poor quality are wastefully discharging about 790 million gallons per day by surface and internal flow. Internal flow in principal problem areas have been identified in Brevard, Charlotte, Clay, De Soto, Duval, Flagler, Glades, Hendry, Hillsborough, Lee, Manatee, Martin, Nassau, and Sarasota Counties. In many areas, uncontrolled discharge over the years has caused a decline in the potentiometric surface locally and regionally, and a deterioration of the potable water aquifers. Programs for control of flowing wells are being carried on by State, county, municipal, or Federal agencies in 21 countries. (Woodard-USGS)

Water-Resources Investigations Report↗

USGS1982

Pacific summary report 2: A revision of Outer Continental Shelf oil and gas activities in the Pacific (Southern California) and their onshore impacts: A summary report, May 1980

The Pacific Outer Continental Shelf (OCS) is an established hydrocarbon-producing region. Oil and gas have been produced from the Santa Barbara Channel (both State and Federal acreage) since 1896. Almost 77,000 barrels of oil are produced from the California Federal OCS each day as of December 1981, and leases on State tidelands produce about 40,000 barrels of oil per day. This highly developed area is, of course, but a small part of the Pacific OCS, which also includes Northern California, Washington, and Oregon. The petroleum industry has expressed interest in exploring frontier areas, and as frontier acreage is offered in future lease sales, exploration, development, and production may move out into deeper water. The technology is currently being developed and tested to allow deepwater exploration. To date, offshore drilling operations have resulted in the delineation of 11 offshore oil and gas fields and 2 gas fields in the Southern California OCS. A recent discovery off Point Arguello, California, may lead to delineation of a new field. Reserve estimates have been made for the known fields in the region. Remaining recoverable reserves are estimated at 787 million barrels of oil and over 1.7 trillion cubic feet of gas as of December 31, 1980. Estimates of undiscovered recoverable resources in the offshore Santa Maria Basin and Southern California OCS are over 3.5 billion barrels of oil and in excess of 5 trillion cubic feet of gas. To date, there have been seven oil and gas lease sales in the Pacific OCS Region. An average of one lease sale per year is scheduled through 1985. Industry interest indicates that the Santa Barbara Channel's potential has not yet been fully explored, and some basins to the south, as well as in the Santa Maria Basin, are now gaining considerable interest. Future exploratory activity in the San Pedro Bay and the Santa Maria Basin is likely to increase. Exploration, development, and production in the Pacific OCS Region are increasing at a moderate pace. Pipelines continue to be the preferred mode of transporting Pacific OCS hydrocarbons to shore. The State and the Federal Governments have expressed a commitment to the use of pipelines where possible and economically feasible. Tankers traveling in the Pacific and entering California ports carry, for the most part, imported oil. The region is active in OCS transportation planning; the Bureau of Land Management works through the Pacific States Regional Technical Working Group Committee. Onshore, the Petroleum Transportation Committee (formerly the Joint Government/Industry Pipeline Working Group) is evaluating a number of transportation scenarios. The nearshore and onshore petroleum processing facilities in the Pacific Region service onshore and offshore oil and gas exploration, development, and production, as well as the international oil market. Many of the onshore facilities have been in operation for years, supporting California's extensive onshore and offshore production. Several new facilities have been proposed, are currently under construction, or have recently opened. Shell Oil opened a crude oil distribution facility near Long Beach in December 1980. Operations began at Union Oil's Mandalay Beach separation and treatment plant in December 1981. The Pacific Offshore Pipeline Company, a subsidiary of the Pacific Lighting Corporation, is planning to build a gas treatment plant at Las Flores Canyon; completion of this project is scheduled for July 1983. It is expected that these new facilities, in addition to the established plants, will be able to accommodate any new OCS production in the near term from previously leased areas.

California↗

USGS2016

Users and uses of Landsat 8 satellite imagery—2014 survey results

Executive Summary In 2013, Landsat 8 began adding high quality, global, moderate-resolution imagery to the more than 40-year archive of Landsat imagery. To assess the potential effects of the availability of Landsat 8 imagery on users and their work, the U.S. Geological Survey (USGS) Land Remote Sensing Program (LRS) initiated a survey of Landsat users. The objectives of the survey were to 1. Characterize various Landsat user groups, such as United States (U.S.) and international users and Landsat 8 and non-Landsat 8 users; 2. Identify any differences among user groups in uses and preferences; 3. Measure the importance of and satisfaction with Landsat 8 attributes; 4. Assess the importance to users of the frequency of usable imagery; and 5. Determine any challenges in using Landsat 8. The online survey was sent to 51,617 Landsat users registered with USGS in May 2014. Almost 13,000 people responded to the survey for a response rate of 25 percent (n = 12,966). Current Landsat users (users who had used Landsat in their work in the year prior to the survey) composed 89 percent of the sample (n = 11,549) and past Landsat users composed 11 percent (n = 1,417). The results reported here apply to current Landsat users registered with the USGS Earth Resources Observation and Science (EROS) Center. Users from 161 countries responded to the survey. Of those, 19 percent were citizens or permanent residents of the United States and 81 percent resided in other countries. More than 70 percent of current users had used Landsat 8 in the year prior to the survey. The majority of Landsat 8 users (65 percent) were established users who used Landsat imagery regularly both before and after Landsat 8 imagery became available. The average current Landsat user was male, 36 years old, and highly educated, with 9 years of experience using satellite imagery or geographic information system (GIS) software. Landsat 8 users had, on average, two more years of experience than non-Landsat 8 users. Users were employed predominantly by academic institutions (65 percent), followed by private businesses (13 percent), Federal governments (10 percent), State and local governments (6 percent), and nonprofit organizations (6 percent). Of the Landsat imagery obtained in the past year by current users, on average 31 percent came from a Landsat 8 sensor. An equivalent amount came from the Landsat 7 ETM+ sensor (33 percent); slightly less came from Landsats 4 and 5 TM sensors (27 percent). Much less came from Landsats 1 through 5 MSS sensors (5 percent). Overall, more than a third of users’ work used Landsat imagery (38 percent). Of this work, on average, 37 percent of the work was operational. Landsat 8 users considered a greater proportion of their work operational than non-Landsat 8 users (39 percent compared with 29 percent). Environmental sciences and management were the most commonly selected primary applications (selected by 42 percent of users). Land use/land cover (23 percent) was the second most commonly selected primary application, followed by education (12 percent), agriculture (9 percent), and planning and development (6 percent). Landsat 8 users were asked to rank the importance of certain attributes in determining whether to use Landsat 8 imagery in their work. The archive was ranked most important, followed by cost, spatial resolution, extent of coverage, data quality, and frequency of revisit. Users were asked how satisfied they were with these same attributes as they currently apply to Landsat 8 imagery. On average, users were most satisfied with lack of cost, extent of coverage, data quality, and the archive, but they were satisfied with all attributes. Users were asked how often they needed Landsat imagery to meet various requirements for their primary application. The survey question specifically asked how often users needed usable imagery, which differs from how often they would like the Landsat satellites to acquire an image. Users were asked to identify their needed frequency of usable imagery for the following levels: 1. Threshold level—the minimum frequency of usable imagery needed to be of any value to their primary application. 2. Breakthrough level—the frequency of usable imagery that would result in a significant improvement for their primary application of the imagery. 3. Target level—the frequency of usable imagery that would only provide a limited additional increase in the expected performance for their primary application. To meet the threshold level, three-quarters of users needed usable imagery every 17 days or less frequently. At the breakthrough level, two-thirds of users (64 percent) needed a usable image every 5–16 days. The current constellation of two satellites (Landsat 7 and 8) is capable of meeting the threshold and breakthrough needs of most users at least some of the time, but a single satellite would be highly unlikely to do so. Two-fifths of users (40 percent) felt that usable imagery provided every 4 days or more frequently would meet their target level which the current Landsat constellation cannot provide. Landsat 8 users were significantly more likely than non-Landsat 8 users to need usable imagery more frequently to meet their target levels. Additionally, U.S. Landsat 8 users were significantly more likely than other Landsat users to need usable imagery more frequently in order meet both their breakthrough and target levels. To explore the effect of the availability of Landsat 8 imagery on Landsat imagery use in general, established users (those who had consistently used Landsat imagery both before and after Landsat 8 imagery became available) using Landsat 8 imagery were asked about changes in the amount of Landsat imagery they used. The majority of established users using Landsat 8 imagery (60 percent) reported an average increase of 51 percent in the number of scenes obtained after Landsat 8 imagery became available. Landsat 8 users were asked if they had encountered challenges in using Landsat 8 whereas non-Landsat 8 users were asked if such challenges had played a role in why they were not using Landsat 8 imagery. Although many users did not encounter challenges when using or trying to use Landsat 8 data, slightly less than 30 percent did encounter issues with processing the data to a usable point. The most common issue reported was not being able to create or have access to a surface reflectance corrected product. Other challenges were related to the file sizes of images being too large to download, store, or analyze. There were no statistically significant differences between Landsat 8 and non-Landsat 8 users in terms of challenges encountered when using or trying to use the imagery, which indicates that users were not unduly discouraged by the challenges they may have encountered. When asked about potential consequences of not using Landsat 8, more than half of the non-Landsat 8 users did not report detrimental effects on their work from not using the imagery. Of those who did report detrimental effects, decreased quality of work, decreased scope of work, and increased time spent on work were the most common.

Open-File Report↗

USGS2021

Feral swine as sources of fecal contamination in recreational waters

Recreational waters are primary attractions at many national and state parks where feral swine populations are established, and thus are possible hotspots for visitor exposure to feral swine contaminants. Microbial source tracking (MST) was used to determine spatial and temporal patterns of fecal contamination in Congaree National Park (CONG) in South Carolina, U.S.A., which has an established population of feral swine and is a popular destination for water-based recreation. Water samples were collected between December 2017 and June 2019 from 18 surface water sites distributed throughout CONG. Host specific MST markers included human (HF183), swine (Pig2Bac), ruminant (Rum2Bac), cow (CowM3), chicken (CL), and a marker for shiga toxin producing Escherichia coli (STEC; stx2 ). Water samples were also screened for culturable Escherichia coli ( E. coli ) as part of a citizen science program. Neither the cow nor chicken MST markers were detected during the study. The human marker was predominantly detected at boundary sites or could be attributed to upstream sources. However, several detections within CONG without concurrent detections at upstream external sites suggested occasional internal contamination from humans. The swine marker was the most frequently detected of all MST markers, and was present at sites located both internal and external to the Park. Swine MST marker concentrations ≥ 43 gene copies/mL were associated with culturable E. coli concentrations greater than the U.S. Environmental Protection Agency beach action value for recreational waters. None of the MST markers showed a strong association with detection of the pathogenic marker ( stx2 ). Limited information about the health risk from exposure to fecal contamination from non-human sources hampers interpretation of the human health implications.

South Carolina↗

USGS1990

Solid-precipitation (snowfall) measurement intercomparison, Bismarck, North Dakota

Difficulties involved in obtaining accurate measurements of solid precipitation (snowfall) have been recognized for many years. Many studies have been conducted to evaluate the accuracy and performance of precipitation gages. These studies show that the type of collection method used can significantly affect the quantity of precipitation measured. Although the types of collection methods evaluated differed for each study and the magnitude of measurement error differed for each study, all of the studies concluded that wind is the major cause of measurement error. Measurement error caused by wind is the result of turbulence and wind speed in the vicinity of the gage orifice (opening). As air rises to pass over the gage, precipitation particles that would have entered the gage orifice are deflected and carried farther downwind. Measurement errors increase as wind speed increases. Studies have shown that measurement errors as great as 80 percent can be attributed to wind. Wind speed and turbulence can be reduced by shielding the gage from the wind. Several types of windshields have been built to decrease wind-related errors. The World Meteorological Organization recognized the need for an international comparison of current methods used for measuring solid precipitation and proposed the Solid Precipitation Measurement Intercomparison. The objectives of the Intercomparison are to: Determine the wind-related errors in methods of solid-precipitation measurements; Derive standard methods for correcting solid-precipitation measurements; Introduce a reference method of solid-precipitation measurement for general use to calibrate any type of precipitation gage; and Establish a complete solid-precipitation data set

Open-File Report↗

USGS1962

Thermodynamic properties of minerals

In the ten years since the publication of the national Bureau of Standards comprehensive tables of thermochemical properties, by Rossini and other (1952), a very large body of modern calorimetric and equilibrium data has become available. Because of the complex interrelations among many thermochemical data and the necessity for internal consistency among these values, a complete revision of this standard reference is required. This is also true of the summaries of thermochemical data for the sulfides (Richardson and Jeffes 1952) and for the oxides (Coughlin 1954). The following tables present critically selected values for the heat and free energy of formation, the logarithm of the equilibrium constant of formation Log K f , the entropy and the molar volume, at 298.15°K (25.0°C) and one atmosphere for minerals.

Trace Elements Investigations↗

USGS2021

Preface to book: Wetland carbon and environmental management

The idea for this book, including its organization and contents, has its origin in the latest environmental and climate policy requirements in the United States, as well as science advances. In 2007, the U.S. Congress passed the Energy Independence and Security Act (EISA), from which Section 712 required U.S. Federal agencies to provide a better understanding of carbon and greenhouse gas fluxes across the United States. As a result, largescale and coordinated efforts were launched to assess carbon storage, carbon fluxes, and greenhouse gas fluxes including CO2, CH4, and N2O from all major terrestrial and freshwater aquatic ecosystems, including forest, grassland/shrub, agricultural lands, wetlands, and rivers, streams, lakes, and impoundments. The EISA assessment produced major results (Selmants et al., 2017; Zhu, 2011; Zhu & McGuire, 2016; Zhu & Reed, 2012, 2014), but recognized that wetlands remained a significant source of uncertainty, especially for those wetlands that were being actively managed. The more recent Second State of the Carbon Cycle Report by the U.S. Global Change Research Program (USGCRP), which devoted two separate chapters to inland and coastal wetlands, respectively, noted that large knowledge gaps still remain, ranging from inadequate analysis of restored and managed wetlands, and consequences of management decisions, to future wetland responses to climate change (USGCRP, 2018). In recent literature, wetland management is suggested as a potential natural solution to mitigate climate change (Fargione et al., 2018, Kroeger et al., 2017) and help offset direct losses of wetlands from sea level rise, subsidence, and coastal erosion (Wang et al., 2017). The recognition that a synthesis of wetland carbon management was urgently needed was the genesis of Wetland Carbon and Environmental Management; discerning the relationships between wetland management and carbon flux (loss or gain) is an international goal.

Geophysical Monograph Series↗

USGS2005

Geography for a Changing World - A science strategy for the geographic research of the U.S. Geological Survey, 2005-2015

This report presents a science strategy for the geographic research of the U.S. Geological Survey (USGS) for the years 2005-2015. The common thread running through the vision, mission, and science goals presented in the plan is that USGS geographers will provide national leadership to understand coupled human-environmental systems in the face of land change and will deliver pertinent information to decisionmakers on the vulnerability and resilience of these systems. We define land change science as the study of the human and environment dynamics that give rise to changed land use, cover, and surface form. A number of realities shape the strategic context of this plan: The Department of Interior Strategic Plan focuses on meeting society’s resource needs and sustaining the Nation’s life support systems, underscoring the importance of characterizing and understanding coupled human-environmental systems. In redefining its mission in the mid-1990s, the USGS envisions itself as an integrated natural science and information agency. The USGS will assume a national leadership role in the use of science to develop knowledge about the web of relations that couple biophysical and human systems and translate this knowledge into unbiased, reliable information that meets important societal information needs. The following trends will influence USGS geography-oriented science activities over the next decade. Most of the emerging earth science issues that the USGS will address are geographic phenomena. A growing international concern for aligning society’s development activities with environmental limits has led to an articulation of a science agenda associated with global environmental change, vulnerability, and resilience. Earth science investigations have evolved toward the study of very large areas, and the resulting huge volumes of data are challenging to manage and understand. Finally, scientists and the public face the challenge of gaining intelligent insights about geographic and environmental processes from these data, with the ultimate goal of guiding resource-management decisions. The first four science goals in the plan support understanding the human and environmental dynamics of land change. Each science goal has an associated set of strategic actions to achieve the goal. These goals and actions are consistent with national science priorities and the Department of Interior and USGS missions, take advantage of existing expertise, and lead to the strengthening of critical geographic research capacities that do not exist in other USGS disciplines.

Circular↗

USGS1990

Modern aerial gamma-ray spectrometry and regional potassium map of the conterminous United States

Aerial gamma-ray surveys of the natural environment measure the flux of gamma rays produced by the radioactive decay of 40 K, 214 Bi, and 208 Tl in the upper 10–20 cm of surface materials. 40 K is a radioactive potassium isotope which can be used to estimate the total amount of potassium in the soils and rocks. 214 Bi is a decay product of the 238 U radioactive decay series and is used to estimate the uranium concentrations, and 208 Tl, a decay product of the 232 Th radioactive decay series, is used to estimate thorium concentrations. Aerial gamma-ray data covering the 48 contiguous states of the United States have been compiled to produce maps showing the distributions of equivalent uranium, equivalent thorium, and potassium. This compilation involved processing the aerial survey data from about 470 1° × 2° quadrangle maps. The aerial gamma-ray data were obtained as part of the National Uranium Resource Evaluation (NURE) Program sponsored by the U.S. Department of Energy during the period 1975-1983. References for the Open-File Reports that describe the surveys and data collection can be found in Bendix Field Engineering Corp. (1983). The aerial surveys were flown by contractors using fixed-wing and helicopter systems with 33-50 L (liters) of thallium-activated sodium iodide (NaI (TI)) crystals. The nominal survey altitude used is 122 m. The survey lines were generally east-west with line spacings of 1.6-10 km. Tie lines were flown perpendicular to the flight lines at intervals of 16- 30 km. The data were corrected for background from aircraft contamination and cosmic rays, altitude variations, airborne 214Bi, and Compton scattering. The gamma-ray systems were calibrated using the calibrations pads at Grand Junction, Colorado (Ward, 1978 ) and the dynamic test strip at Lake Mead, Arizona (Geodata International, Inc., 1977).

Journal of Geochemical Exploration↗

USGS1977

GEOTHERM user guide

GEOTHERM is a computerized geothermal resources file developed by the U.S. Geological Survey. The file contains data on geothermal fields, wells, and chemical analyses from the United states and international sources. The General Information Processing System (GIPSY) in the IBM 370/155 computer is used to store and retrieve data. The GIPSY retrieval program contains simple commands which can be used to search the file, select a narrowly defined subset, sort the records, and output the data in a variety of forms. Eight commands are listed and explained so that the GEOTHERM file can be accessed directly by geologists. No programming experience is necessary to retrieve data from the file.

Open-File Report↗

USGS2016

Carbon and oxygen isotopic composition of coal and carbon dioxide derived from laboratory coal combustion: A preliminary study

The concentration of carbon dioxide (CO 2 ) in the atmosphere has dramatically increased from the start of the industrial revolution in the mid-1700s to present levels exceeding 400 ppm. Carbon dioxide derived from fossil fuel combustion is a greenhouse gas and a major contributor to on-going climate change. Carbon and oxygen stable isotope geochemistry is a useful tool to help model and predict the contributions of anthropogenic sources of CO 2 in the global carbon cycle. Surprisingly few studies have addressed the carbon and oxygen isotopic composition of CO 2 derived from coal combustion. The goal of this study is to document the relationships between the carbon and oxygen isotope signatures of coal and signatures of the CO 2 produced from laboratory coal combustion in atmospheric conditions. Six coal samples were selected that represent various geologic ages (Carboniferous to Tertiary) and coal ranks (lignite to bituminous). Duplicate splits of the six coal samples were ignited and partially combusted in the laboratory at atmospheric conditions. The resulting coal-combustion gases were collected and the molecular composition of the collected gases and isotopic analyses of δ 13 C of CO 2 , δ 13 C of CH 4 , and δ 18 O of CO 2 were analysed by a commercial laboratory. Splits (~ 1 g) of the un-combusted dried ground coal samples were analyzed for δ 13 C and δ 18 O by the U.S. Geological Survey Reston Stable Isotope Laboratory. The major findings of this preliminary work indicate that the isotopic signatures of δ 13 C (relative to the Vienna Pee Dee Belemnite scale, VPDB) of CO 2 resulting from coal combustion are similar to the δ 13 C VPDB signature of the bulk coal (− 28.46 to − 23.86 ‰) and are not similar to atmospheric δ 13 C VPDB of CO 2 (~ − 8 ‰, see http://www.esrl.noaa.gov/gmd/outreach/isotopes/c13tellsus.html ). The δ 18 O values of bulk coal are strongly correlated to the coal dry ash yields and appear to have little or no influence on the δ 18 O values of CO 2 resulting from coal combustion in open atmospheric conditions. There is a wide range of δ 13 C values of coal reported in the literature and the δ 13 C values from this study generally follow reported ranges for higher plants over geologic time. The values of δ 18 O (relative to Vienna Standard Mean Ocean Water) of CO 2 derived from atmospheric combustion of coal and other high-carbon fuels (peat and coal) range from + 19.03 to + 27.03‰ and are similar to atmospheric oxygen δ 18 O VSMOW values which average + 23.8‰. Further work is needed on a broader set of samples to better define the relationships between coal composition and combustion-derived gases.

International Journal of Coal Geology↗

USGS1978

Think Metric

The International System of Units, as the metric system is officially called, provides for a single "language" to describe weights and measures over the world. We in the United States together with the people of Brunei, Burma, and Yemen are the only ones who have not put this convenient system into effect. In the passage of the Metric Conversion Act of 1975, Congress determined that we also will adopt it, but the transition will be voluntary.

Report↗

USGS1986

Observations of the eruptions of July 22 and August 7, 1980, at Mount St. Helens, Washington

The explosive eruptions of July 22 and August 7, 1980, at Mount St. Helens, Wash., both included multiple eruptive pulses. The beginnings of three of the pulses-two on July 22 and one on August 7-were witnessed and photographed. Each of these three began with a fountain of gases and pyroclasts that collapsed around the vent and generated a pyroclastic density flow. Significant vertical-eruption columns developed only after the density flows were generated. This behavior is attributable to either an increase in the gas content of the eruption jet or a decrease in vent radius with time. An increase in the gas content may have occurred as the vent was cleared (by expulsion of a plug of pyroclasts) or as the eruption began to tap deeper, gas-rich magma after first expelling the upper, gas-depleted part of the magma body. An effective decrease of the vent radius with time may have occurred as the eruption originated from progressively deeper levels in the vent. All of these processes-vent clearing; tapping of deeper, gas-rich magma; and effective decrease in vent radius-probably operated to some extent. A 'relief-valve' mechanism is proposed here to account for the occurrence of multiple eruptive pulses. This mechanism requires that the conduit above the magma body be filled with a bed of pyroclasts, and that the vesiculation rate in the magma body be inadequate to sustain continuous eruption. During a repose interval, vesiculation of the magma body would cause gas to flow upward through the bed of pyroclasts. If the rate at which the magma produced gas exceeded the rate at which gas escaped to the atmosphere, the vertical pressure difference across the bed of pyroclastic debris would increase, as would the gas-flow rate. Eventually a gas-flow rate would be achieved that would suddenly diminish the ability of the bed to maintain a pressure difference between the magma body and the atmosphere. The bed of pyroclasts would then be expelled (that is, the relief valve would open) and an eruption would commence. During the eruption, gas would be lost faster than it could be replaced by vesiculation, so the gas-flow rate in the conduit would decrease. Eventually the gas-flow rate would decrease to a value that would be inadequate to expel pyroclasts, so the conduit would again become choked with pyroclasts (that is, the relief valve would close). Another period of repose would commence. The eruption/repose sequence would be repeated until gas-production rates were inadequate to reopen the valve, either because the depth of the pyroclast bed had become too great, the volatile content of the magma had become too low, or the magma had been expended. A timed sequence of photographs of a pyroclastic density flow on August 7 indicates that, in general, the velocity of the flow front was determined by the underlying topography. Observations and details of the velocity/topography relationship suggest that both pyroclastic flows and pyroclastic surges formed. The following mechanism is consistent with the data. During initial fountain collapse and when the flow passed over steep, irregular terrain, a highly inflated suspension of gases and pyroclasts formed. In this suspension, the pyroclasts underwent rapid differential settling according to size and density; a relatively low-concentration, fine-grained upper phase formed over a relatively high-concentration coarse-grained phase. The low-particle-concentration phase (the pyroclastic surge) was subject to lower internal friction than the basal high-concentration phase (the pyroclastic flow), and so accelerated away from it. The surge advanced until it had deposited so much of its solid fraction that its net density became less than that of the ambient air. At this point it rose convectively off the ground, quickly decelerated, and was overtaken by the pyroclastic flow. The behavior of the flow of August 7 suggests that a pyroclastic density flow probably expands through the ingestion of ai

Professional Paper↗

USGS1984

Between Mount St. Helens and the world: How the U.S. Geological Survey provided news-media information on the 1980 volcanic eruptions

The eruptions of Mount St. Helens volcano, Wash., constituted one of the major national and international news stories of 1980 and involved the U.S. Geological Survey in more news coverage than any other event in its history. Much of the information about the volcano came from monitoring and research by geologists, geophysicists, hydrologists, and other scientists of the U.S. Geological Survey. This scientific information was distributed to the public, through news media, by U.S. Geological Survey personnel. Key members of this group were Mount St. Helens hazards assessment scientists, monitoring scientists, and research scientists; public affairs officers; and the Information Scientist for Mount St. Helens. The Information Scientist, a geologist or geophysicist, assumed the major role of on-site (Vancouver, Wash.) news spokesman about a week after the main eruption of May 18. The Geological Survey released information through news conferences, interviews, news pools of reporters and cameramen on trips to the volcano, special television and radio appearances, news releases, and informal contacts with reporters. Members of the U.S. Forest Service, Federal Emergency Management Agency, State of Washington, and other government agencies cooperated extensively with the Geological Survey. By providing assistance to news representatives, the Geological Survey and these other agencies helped effect rapid dissemination of the background information and daily events of a highly complex story while limiting disruption to the scientific working team and minimizing dangers to reporters and scientists.

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