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Gilbert White talks about natural hazards

Dr. Gilbert White is Director of the Institute of Behavioral Science at the University of Colorado, Boulder, where he is responsible for natural Hazards Research and Applications Information Center supported by the National Science Foundation. He served in the Executive Office of the president in 1941-42, on the Federal Flood Control Policy Task Force in 1964-65, and on the U.S Geological Survey Advisory Panel on Earthquake Studies. Dr. White has authored five books on the social and economic aspects of natural resources, including water supply and river development, and on floods and other natural hazards.

Earthquake Information Bulletin (USGS)

U.S. Geological Survey Library classification system

The U.S. Geological Survey library classification system has been designed for an earth science library. It is a tool for assigning classification numbers to earth science and allied pure science library materials in order to collect these materials into related subject groups on the library shelves and arrange them alphabetically by author and title. It can also be used as a retrieval system to access these materials through the subject and visible geographic classification numbers. The classification scheme has been developed over the years since 1904 to meet the ever-changing needs of increased specialization and new areas of study in the earth sciences. This system contains seven schedules: Subject schedule Geological survey schedule Earth science periodical schedule Government documents periodical schedule General science periodical schedule Earth science maps schedule Geographic schedule A geographic number, from the geographic schedule, is distinguished from other numbers in the system in that it is always enclosed in parentheses; for example, (200) is the geographic number for the United States. The geographic number is used in conjunction with the six other previously listed schedules, and it represents slightly different nuances of meanings, in respect to geographic locale, for each schedule. When used with a subject number, the geographic number indicates the country, state, province, or region in which the research was made. The subject number, 203, geology, when combined with the geographic number, (200), for example 203(200), is the classification number for library materials on the geology of the United States. The geographic number, combined with the capital letter G, for example, G(211), is the classification number for an earth science periodical issued by a geological association or university geology department in the State of Maine. When the letter S is combined with a geographic number, for example, S(276), it represents a general science periodical for a university or association in California. When the letter P is combined with a geographic number, for example, P(200), it represents a governmental periodical issued by the United States Federal Government. Geographic numbers standing alone represent classification numbers for the publications of geological surveys; for example, (200) represents publications of the U.S. Geological Survey. Map call numbers have a geographic number preceded by the capital letter M, followed by an abbreviated subject number. For example: M(200)2 where: M = Map (200) = Geographic region of the United States 2 = Abbreviation for the subject number 203— geology. The introduction, which follows this abstract, provides detailed procedures on the construction of complete call numbers for works falling into the framework of the aforesaid classification schedules. The tables following the introduction can be quickly accessed through the use of the newly expanded subject index. The purpose of this publication is to provide the earth science community with a classification and retrieval system for earth science materials, to provide sufficient explanation of its structure and use, and to enable library staff and clientele to classify or access research materials in a library collection.

Bulletin

U.S. Geological Survey Library classification system

The U.S. Geological Survey Library classification system has been designed for earth science libraries. It is a tool for assigning call numbers to earth science and allied pure science materials in order to collect these materials into related subject groups on the library shelves and arrange them alphabetically by author and title. The classification can be used as a retrieval system to access materials through the subject and geographic numbers. The classification scheme has been developed over the years since 1904 to meet the ever-changing needs of increased specialization and the development of new areas of research in the earth sciences. The system contains seven schedules: Subject schedule Geological survey schedule Earth science periodical schedule Government document periodical schedule General science periodical schedule Earth science map schedule Geographic schedule Introduction provides detailed instructions on the construction of call numbers for works falling into the framework of the classification schedules. The tables following the introduction can be quickly accessed through the use of the newly expanded subject index. The purpose of this publication is to provide the earth science community with a classification and retrieval system for earth science materials, to offer sufficient explanation of its structure and use, and to enable library staff and clientele to classify or access research materials in a library collection.

Bulletin

Selected papers in the applied computer sciences 1992

This compilation of short papers reports on technical advances in the applied computer sciences. The papers describe computer applications in support of earth science investigations and research. This is the third volume in the series "Selected Papers in the Applied Computer Sciences." Listed below are the topics addressed in the compilation: Integration of geographic information systems and expert systems for resource management, Visualization of topography using digital image processing, Development of a ground-water data base for the southeastern Uited States using a geographic information system, Integration and aggregation of stream-drainage data using a geographic information system, Procedures used in production of digital geologic coverage using compact disc read-only memory (CD-ROM) technology, and Automated methods for producing a technical publication on estimated water use in the United States.

Bulletin

Activities in tectonics of Research Committee of American Association of Petroleum Geologists

During 1945 and 1946, the Research Committee of the American Association of Petroleum Geologists, under the chairmanship of Shepard W. Lowman, has been engaged in “a reconnaissance survey of research in petroleum geology and allied sciences with explicit reference to exploration” in order “to formulate a comprehensive research program which the American Association of Petroleum Geologists may adopt as its recommendation for that research most needed to improve our ability to find oil” [see “References” at end of report, Lowman, 1945]. In order to make this survey, the field was divided among a number of subcommittees, including a Subcommittee on Tectonics, of which the writer was chairman. Preliminary reports, discussing the research possibilities in the various fields covered by the subcommittees, were submitted in January, 1946, and concrete recommendations were formulated by the Research Committee at the Chicago meeting of the Association in April 1946 [Lowman, 1946]. Final reports of the subcommittees will be published later in 1946 in the Bulletin of the American Association of Petroleum Geologists.

Eos, Transactions, American Geophysical Union

Index to the known fossil insects of the world, including myriapods and arachnids

With the view of furthering study in the too neglected field of fossil insects, I transmit herewith for publication the card catalogue of described fossil insects which I have used for twenty years and kept constantly up to date, and which has greatly facilitated my own researches. It is believed to be practically complete. At least where insects are figured, and in many other cases where they are the first or only references from a given locality, entries are given where only the genus, the family, or even the order is mentioned. This has been done because the early literature of fossil insects is essentially vague and general, but it should not for that reason be wholly overlooked ; and to-day our knowledge of the occurrence of insects of a particular locality, even when of recent discovery, is not infrequently confined to statements of a general nature, which, if not brought to view or mind in a list like this, would be lost sight of, while their recognition may lead to further local investigation, to the earlier benefit of science. It is in no sense a systematic catalogue, and except occasionally in the notes contains no immediate results of investigation. No questions of synonymy are settled. The entries are made as the authors quoted gave them, with only the corrections of spelling required; it follows that the same insect appears at several points, to which the student is referred by full cross-references, and that more than one insect may (though probably rarely does) figure under one name. In one or two such instances, where the same name has been given by inadvertence to two totally different creatures, the later one is separated from the earlier. For convenience' sake, the entries are grouped into large sections, nearly identical with those I have employed in my systematic review of fossil insects (Bulletin 31, U. S. Geological Survey), by which method the insects from the Primary, Secondary, and Tertiary rocks are kept distinct; but otherwise the entries are purely alphabetical under the orders. It should be noticed, however, that the vague references to groups higher than genera are brought together at the beginning of each alphabet, first the most vague, and then those which permit some alphabetization. In these cases the primary or secondary alphabetization is first by authors, second by dates, and in all cases where under one entry there is more than one date the order therein is chronological. In a previous bulletin (Bulletin 69, U. S. Geological Survey) is given a complete bibliography of the literature from which these entries are taken, and the two works are thus complementary to each other.

Bulletin

U.S. Geological Survey Trace Elements and related reports through 1954

This report supersedes TEI-400, "U.S. Geological Survey Trace Elements and related reports through 1953." Part I is a numerical list of U.S. Geological Survey Trace Elements Investigations and Memorandum reports. This part lists not only reports (followed by a date) that have been transmitted to the U.S> Atomic Energy Commission, but also reports in preparation (followed by an asterisk) for which tentative titles were available on December 31, 1954. If a report, or portion of a report, has been published, the fact is indicated by the abbreviation of the medium of publication. (See also Part II.) Part II is a reference guide to Trace Elements and related reports that are available to the public (this part supersedes Part I of Bulletin 1019-B). These reports are grouped according to the type of publication or release. If a report, or portion of the report, has been published in more than one form, appropriate cross-references are given to indicate the other forms of publication. Abstracts published in Nuclear Science Abstracts are not included in Part II; however, if the abstract of a Trace Elements report has been published in NSA, the fact is indicated in Part I. Publications in process on December 31, 1954, are designated by an asterisk. Part III is a finding list of states, areas, and subjects and supersedes Part II of Bulletin 1019-B. It is based on information derived mostly from the titles of reports and, where titles are of general nature, from a cursory review of the reports. This list is not a complete index of the information given in Trace Elements and related reports, but is designed to find subjects of major interest, Because of the numerous entries for Colorado and Utah, information has been listed by counties and, where possible, by subject under these states. Other states have county listings only if a county is included in the title of a report; otherwise, area may be listed separately under the state. Major subjects are listed separately in the index and also, where appropriate under states. Analytical methods and subjects related to analytical research are listed under Analytical Methods and Research, but not separately throughout the index. Most mineralogic studies are included under the heading Mineralogy, but are not necessarily listed according to location. Part IV is an author index. The words “with” and “and” are used to indicate seniority of authorship. For example, a listing of Smith and Brown indicated that Smith is the senior author. A listing of Smith with Brown indicates that Brown is the senior author. In both parts III and IV all Trace Elements reports are listed, as well as other related reports that have not been issued as Trace Elements reports. The following abbreviations have been used: TEI, Trace Elements Investigations report; TEM, Trace Elements Memorandum report; OF, open file; TIS, Technical Information Service release; C, Circular; B, Bulletin; P, Professional Paper; MC, Maps and Charts; J, Journal; and NSA, Nuclear Science Abstracts.

Trace Elements Investigations

Technical Manual for the Geospatial Stream Flow Model (GeoSFM)

The monitoring of wide-area hydrologic events requires the use of geospatial and time series data available in near-real time. These data sets must be manipulated into information products that speak to the location and magnitude of the event. Scientists at the U.S. Geological Survey Earth Resources Observation and Science (USGS EROS) Center have implemented a hydrologic modeling system which consists of an operational data processing system and the Geospatial Stream Flow Model (GeoSFM). The data processing system generates daily forcing evapotranspiration and precipitation data from various remotely sensed and ground-based data sources. To allow for rapid implementation in data scarce environments, widely available terrain, soil, and land cover data sets are used for model setup and initial parameter estimation. GeoSFM performs geospatial preprocessing and postprocessing tasks as well as hydrologic modeling tasks within an ArcView GIS environment. The integration of GIS routines and time series processing routines is achieved seamlessly through the use of dynamically linked libraries (DLLs) embedded within Avenue scripts. GeoSFM is run operationally to identify and map wide-area streamflow anomalies. Daily model results including daily streamflow and soil water maps are disseminated through Internet map servers, flood hazard bulletins and other media.

Open-File Report

Deformation band clusters on Mars and implications for subsurface fluid flow

High-resolution imagery reveals unprecedented lines of evidence for the presence of deformation band clusters in layered sedimentary deposits in the equatorial region of Mars. Deformation bands are a class of geologic structural discontinuity that is a precursor to faults in clastic rocks and soils. Clusters of deformation bands, consisting of many hundreds of individual subparallel bands, can act as important structural controls on subsurface fluid flow in terrestrial reservoirs, and evidence of diagenetic processes is often preserved along them. Deformation band clusters are identified on Mars based on characteristic meter-scale architectures and geologic context as observed in data from the High-Resolution Imaging Science Experiment (HiRISE) camera. The identification of deformation band clusters on Mars is a key to investigating the migration of fluids between surface and subsurface reservoirs in the planet's vast sedimentary deposits. Similar to terrestrial examples, evidence of diagenesis in the form of light- and dark-toned discoloration and wall-rock induration is recorded along many of the deformation band clusters on Mars. Therefore, these structures are important sites for future exploration and investigations into the geologic history of water and water-related processes on Mars.

Geological Society of America Bulletin

Current activity on the Martian surface: A key subject for future exploration

One of the fundamental discoveries in Mars science in the last decade has been the extent and importance of current surface activity. Recent results have shifted our view of Mars from a world where the most interesting geologic events were in the distant past (similar to the Moon) to a world that undergoes active evolution and one where understanding the present is key to deciphering the planet’s history. When input was requested for the last Planetary Science Decadal Survey, some observations of surface changes had been published, but the number of detections was small and their significance not fully appreciated. Since that time, detections have proliferated, driven primarily by the long-term operation of the Mars Reconnaissance Orbiter (MRO) and the High Resolution Imaging Science Experiment (HiRISE) as well as landed observations of aeolian activity. In addition to observed changes, theory suggests that additional important surface processes are likely active but not yet observed because orbital data are limited in space and time and landed studies are rare. Understanding current Martian surface processes is a fundamental science question in itself, as it provides a test for physical and terrestrial analog-based models of specific geological processes acting under non-Earth planetary and environmental conditions. It is also an essential step for reading Mars’ geologic history and providing input to climate models: without understanding current dynamic processes, we cannot understand how they have varied during recent climate cycles, nor how they are reflected in ancient rock or modern ice records. Understanding the rates and types of current surface activity is also highly relevant to selecting geological samples, setting Planetary Protection rules, and understanding the hazards and environment that would be experienced by future human explorers.

Bulletin of the AAS

The Coyote Mountains’ desert snail (Sonorelix harperi carrizoensis), a lazarus species With the first documentation of live individuals

The Coyote Mountain desert snail ( Sonorelix harperi carrizoensis ) was described in 1937 from 30 dry shells collected the previous year. We reviewed the literature and museum records and found two additional shell collections for this subspecies from the type locality one from 1958, and one from an adjacent mountain range in 1938. There is no evidence previously of any live snails being collected from the Coyote Mountains, Imperial County, California. All shell collections of S. harperi carrizoensis have the same locality data as the type series, which is Painted Gorge, Coyote Mountains except for one recorded collection of shells from the Vallecito Mountains from 1938. Using geological maps and other data sources, a potential mesic habitat was identified in the Coyote Mountains. During recent field work for salamanders at this location we detected two live specimens of S. harperi carrizoensis approximately 2 km north of its type location. This new data confirms this subspecies is still extant and has occurred at least at two sites historically in these mountains. Despite the presence of mesic habitats (i.e., mosses, liverworts and ferns) at the type locality, we found no evidence of S. harperi carrizoensis or salamanders.

California

Seismic tomography 2023

Seismic tomography is the most abundant source of information about the internal structure of the Earth at scales ranging from a few meters to thousands of kilometers. It constrains the properties of active volcanoes, earthquake fault zones, deep reservoirs and storage sites, glaciers and ice sheets, or the entire globe. It contributes to outstanding societal problems related to natural hazards, resource exploration, underground storage, and many more. The recent advances in seismic tomography are being translated to nondestructive testing, medical ultrasound, and helioseismology. Nearly 50 yr after its first successful applications, this article offers a snapshot of modern seismic tomography. Focused on major challenges and particularly promising research directions, it is intended to guide both Earth science professionals and early‐career scientists. The individual contributions by the coauthors provide diverse perspectives on topics that may at first seem disconnected but are closely tied together by a few coherent threads: multiparameter inversion for properties related to dynamic processes, data quality, and geographic coverage, uncertainty quantification that is useful for geologic interpretation, new formulations of tomographic inverse problems that address concrete geologic questions more directly, and the presentation and quantitative comparison of tomographic models. It remains to be seen which of these problems will be considered solved, solved to some extent, or practically unsolvable over the next decade.

Bulletin of the Seismological Society of America

The Geologic Story of the Uinta Mountains

The opening of the West after the Civil War greatly stimulated early geologic exploration west of the 100th Meridian. One of the areas first studied, the Uinta Mountains region, gained wide attention as a result of the explorations of three Territorial Surveys, one headed by John Wesley Powell, one by Clarence King, and one by Ferdinand V. Hayden. Completion of the Union Pacific Railroad across southern Wyoming 100 years ago, in 1869, materially assisted geologic exploration, and the railheads at Green River and Rock Springs greatly simplified the outfitting of expeditions into the mountains. The overlap of the Powell, King, and Hayden surveys in the Uinta Mountains led to efforts that were less concerted than competitive and not without acrimony. Many parts of the area were seen by all three parties at almost the same time. Duplication was inevitable, of course, but all three surveys contributed vast quantities of new knowledge to the storehouse of geology, and many now-basic concepts arose from their observations. Powell's area of interest extended mainly southward from the Uinta Mountains to the Grand Canyon, including the boundless plateaus and canyons of southern Utah and northern Arizona. King's survey extended eastward from the High Sierra in California to Cheyenne, Wyoming, and encompassed a swath of country more than 100 miles wide. Hayden's explorations covered an immense region of mountains and basins from Yellowstone Park in Wyoming southeast throughout most of Colorado. Powell first entered the Uinta Mountains in the fall of 1868, having traveled north around the east end of the range from the White River country to Green River, Wyoming, then south over a circuitous route to Flaming Gorge and Browns Park, and finally back to the White River, where he spent the winter. In 1869, after reexamining much of the area visited the previous season, Powell embarked on his famous 'first boat trip' down the Green and Colorado Rivers. This trip was more exploratory than scientific; his second, more scientific trip was made 2 years later. Powell revisited the Uinta Mountains in 1874 and 1875 to complete the studies begun 6 years earlier. His classic 'Report on the Geology of the Eastern Portion of the Uinta Mountains and a Region of Country Adjacent Thereto' was published in 1876. King's survey?officially 'The United States Geological Exploration of the Fortieth Parallel'?is better known simply as the '40th Parallel Survey.' King began working eastward from California in 1867. The Uinta Mountains region, however, was mapped by S. F. Emmons, under the supervision of King, in the summers of 1869 and 1871. Emmons' work was monumental, and although he emphasized in his letter of transmittal to King the exploratory nature of the work?as the formal title of the report indicates?his maps, descriptions, and conclusions reflect a comprehensive understanding of the country and its rocks. The 40th Parallel report contains the best, most complete early descriptions of the Uinta Mountains. It, indeed, is a treasurechest of information and a landmark contribution to the emerging science of geology. Hayden visited the Uinta Mountains in 1870, descending the valley of Henrys Fork to Flaming Gorge in the fall after having earlier examined the higher part of the range to the west. Most of Hayden's observations were cursory, and he repeatedly expressed regret at having insufficient time for more detailed studies. In reference to the area between Clay Basin and Browns Park, he remarked (Hayden, 1871, p. 67) somewhat dryly that 'the geology of this portion of the Uinta range is very complicated and interesting. To have solved the problem to my entire satisfaction would have required a week or two.' Eighty-odd years later I spent several months there?looking at the same rocks. Powell was perhaps more creative?more intuitive?than either King or Hayden, and his breadth of interest in the fields of geology, physiography, ethnology, an

Bulletin

A scientific vision and roadmap for earthquake rupture forecast developments, a USGS perspective

We articulate a scientific vision and roadmap for the development of improved Earthquake Rupture Forecast models, which are one of the two main modeling components used in modern seismic hazard and risk analysis. One primary future objective is to provide fully time-dependent models that include both elastic rebound and spatiotemporal clustering nationwide, which is particularly important for shorter-term hazard and risk considerations (e.g., earthquake insurance products). We also discuss the importance and perennial challenges associated with quantifying epistemic uncertainties, including those associated with deformation-model slip rates, un-quantified sampling errors with respect to off-fault seismicity, and any spatial covariances. The need for more physics-based approaches is also emphasized, as is the benefit of adding model valuation (quantifying usefulness) to our verification and validation protocols. Given the multidisciplinary and system-level nature of this activity, modular design is critical. Future updates will also draw from best-available science by both the United States Geological Survey and the external community. The primary goal of this paper is to highlight plans that guide research and facilitate community engagement with model development, especially with respect to lowering the entry barrier for early career scientists and engineers. The paper is written so readers can focus on the sections that interest them most (see table of contents), with the Introduction and Discussion providing a stand-alone overview and summary.

Bulletin of the Seismological Society of America

Science and technology requirements to explore caves in our Solar System

We are in the incipient phase of exploring the subterranean realm of our Solar System. Planetary caves research offers interdisciplinary, cross-planetary body investigations spanning geology, climatology, astrobiology, robotics, and human use. Caves are of great importance in advancing our understanding of planetary processes and the search for life beyond Earth. Given these advances, a diverse and interdisciplinary community of planetary caves researchers has emerged. Their activities have been partially documented by a series of workshops and conferences over the last thirteen years (Titus & Boston, 2012; Wynne et al, 2016; Titus et al., 2020, submitted). These meetings brought together scientists and engineers from around the world to discuss both science needs (i.e., geology, habitability, and astrobiology), as well as engineering challenges (e.g., mobility, navigation, and communications) for cave research on other planetary bodies. It was determined at the last planetary caves conference that a goals and/or roadmap document, like those of the Assessment and Advisory Groups, was needed. This white paper is our initial conception of such an effort.

Bulletin of the AAS

On the use of high-resolution topographic data as a proxy for seismic site conditions (V S30 )

An alternative method has recently been proposed for evaluating global seismic site conditions, or the average shear velocity to 30 m depth (V S30 ), from the Shuttle Radar Topography Mission (SRTM) 30 arcsec digital elevation models (DEMs). The basic premise of the method is that the topographic slope can be used as a reliable proxy for V S30 in the absence of geologically and geotechnically based site-condition maps through correlations between VS30 measurements and topographic gradient. Here we evaluate the use of higher-resolution (3 and 9 arcsec) DEMs to examine whether we are able to resolve V S30 in more detail than can be achieved using the lower-resolution SRTM data. High-quality DEMs at resolutions greater than 30 arcsec are not uniformly available at the global scale. However, in many regions where such data exist, they may be employed to resolve finer-scale variations in topographic gradient, and consequently, V S30 . We use the U.S. Geological Survey Earth Resources Observation and Science (EROS) Data Center's National Elevation Dataset (NED) to investigate the use of high-resolution DEMs for estimating V S30 in several regions across the United States, including the San Francisco Bay area in California, Los Angeles, California, and St. Louis, Missouri. We compare these results with an example from Taipei, Taiwan, that uses 9 arcsec SRTM data, which are globally available. The use of higher-resolution NED data recovers finer-scale variations in topographic gradient, which better correlate to geological and geomorphic features, in particular, at the transition between hills and basins, warranting their use over 30 arcsec SRTM data where available. However, statistical analyses indicate little to no improvement over lower-resolution topography when compared to V S30 measurements, suggesting that some topographic smoothing may provide more stable V S30 estimates. Furthermore, we find that elevation variability in canopy-based SRTM measurements at resolutions greater than 30 arcsec are too large to resolve reliable slopes, particularly in low-gradient sedimentary basins.

Bulletin of the Seismological Society of America

Understanding natural systems; a perspective for land-use planning in Appalachian Kentucky

An eight-county area at the headwaters of the Kentucky River has been designated the Kentucky River Area Development District (KRADD) by the Appalachian Regional Commission. The objective of the project described in this report has been to provide materials to KRADD planners in a format and containing terminology usable by local people untrained in earth science. Experimental maps (not included in this report) have been prepared largely from preexisting data. Time and cost limitations required a regional analysis as well as somewhat more detailed examples of selected localities. Most of the maps produced to meet these needs show the abundance and distribution of naturally occurring materials and the areas affected by various geomorphic processes. Three types of maps, showing current land use, slope, and flood-prone areas, present both basic and derived data directly applicable to specific land-use decisions. Basic map information on quality and quantity of surface and ground water, bedrock and surficial geology, and mineral fuels can be interpreted for a wide variety of current and potential uses. Texts accompanying the maps explain bedrock control of geomorphic processes, distribution and significance of surficial deposits, and hydrologic characteristics of the intricately dissected eastern Kentucky terrain. Within this conceptual framework, geomorphic processes and the landscape may be evaluated in humanly significant terms of low to high potential risk, thereby indicating both opportunities and limitations for land use.

Kentucky

Geologic studies in Alaska by the U.S. Geological Survey, 1993

This collection of 19 papers continues the annual series of U.S. Geological Survey reports on geologic investigations in Alaska. Contributions include 14 Articles and 5 shorter Geologic Notes that report results from all corners of the State. USGS activities in Alaska cover a broad spectrum of earth science topics, including the environment, hazards, resources, and geologic framework studies. Three articles focus on the environmental geochemistry of parts of south-central, west-central, and southwestern Alaska. An article on methane released from permafrost near Fairbanks and a note on paleowind direction indicators on the Arctic coastal plain contribute to ongoing climate and paleoclimate investigations. Landslide hazards in the Talkeetna Mountains and Wrangell-St. Elias National Park are discussed in two notes. Possible active fault traces near Alaska's main population center are described in an article on the Castle Mountain fault. An article on Aniakchak volcano presents evidence for a previously unrecognized catastrophic flooding event. Resources and resource assessment on gold, base metals, and coal are discussed in several articles and a note. Geologic framework studies cover tectonics, paleontology, stratigraphy, and metamorphic petrology. One contribution involves field methods; it evaluates the relative accuracy of global positioning systems and topographic map-based methods for deriving location data for field stations. Two bibliographies at the end of the volume list reports about Alaska in USGS publications released in 1993 and reports about Alaska by USGS authors in non-USGS publications in 1993.

Alaska