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Antarctica: A Keystone in a Changing World--Online Proceedings for the Tenth International Symposium on Antarctic Earth Sciences. Santa Barbara, California, U.S.A.--August 26 to September 1, 2007

Overview: The International Symposium on Antarctic Earth Sciences (ISAES) is held once every four years to provide an international forum for presenting research results and new ideas and for planning future Antarctic geoscience research projects. This Tenth ISAES coincides with the International Polar Year (IPY; 50th Anniversary of the International Geophysical Year) and has been structured to showcase the great breadth of geoscience research being done in Antarctic regions by more than more than 100 institutions located in over 30 countries. The science program of the Symposium encompasses six broad themes that cover key topics on evolution and interactions of the geosphere, cryosphere and biosphere and their cross-linkages with past and historic paleoclimates. Emphasis is also on deciphering the climate records in ice cores, geologic cores, rock outcrops and those inferred from climate models. New technologies for the coming decades of geoscience data collection are also highlighted. Ten keynote presentations at the symposium outline the foundation for the research sessions of the symposium and the structure of the Online Proceedings and Proceedings Book for the Tenth ISAES. The ISAES is traditionally a cornerstone meeting for the Scientific Committee on Antarctic Research (SCAR). In recognition of the Tenth ISAES being held in the U.S. for the first time in 30 years and during IPY, the publication of the symposium proceedings is being handled as a special collaborative effort of the U.S. National Science Foundation, the U.S. Geological Survey, The National Academies Polar Research Board and The National Academies Press. The National Academies Polar Research Board oversees the activities of SCAR in the U.S. Special attention has been directed at publication formats for the symposium, to expedite the open and wide sharing of mature and preliminary research results presented in talks and posters at the Tenth ISAES. All symposium presentations are documented by a short Summary printed in the Symposium Program Booklet and either a short research paper or an extended abstract. The research papers and extended abstracts are compiled in this Online Proceedings and are replicated on a DVD-ROM that is placed in the back of the Tenth ISAES Proceedings Book. The Proceedings Book has printed versions of the keynote talks and an overview paper of the symposium. The short research papers and extended abstracts have been handled differently. Research papers present mature research results and syntheses. They have been peer-reviewed using standard journal procedures. Following revisions and acceptances by co-editors, the papers have been formatted for publication and proofread by authors. Each paper has been assigned a Digital Object Identification (DOI) number and separate html link, and posted online (as part of this USGS Open-File Report series) to ensure open and wide access to the research results. Extended abstracts focus on preliminary research results and have not been peer reviewed. They have had only minimal editorial review and revision. Authors have formatted and proofread their papers. Extended abstracts were not given DOI numbers and are included together in a separate chapter of this online Proceedings. USGS publications staff and Stanford-student editorial assistants indexed and compiled the PDF versions of the short research papers and extended abstracts for inclusion in this online Proceedings. USGS staff created the master DVD-ROM that contains a replica of the Online Proceedings for the Tenth ISAES, and provided the DVD-ROM copies that are included in the Tenth ISAES Proceedings Book published by The National Academies Press in the U.S. A team of more than 25 co-editors coordinated with the numerous authors and peer reviewers in handling the many research papers and extended abstracts that are included herein. Handling the large volume of short papers and extended abstracts, getting most of them onli

Open-File Report↗

The 16th International Geological Congress, Washington, 1933

In 1933, the International Geological Congress (IGC) returned to the United States of America (USA) for its sixteenth meeting, forty-two years after the 5 th IGC convened in Washington. The Geological Society of America and the U.S. Geological Survey (USGS) supplied the major part of the required extra-registration funding after the effects of the Great Depression influenced the 72 th U.S. Congress not to do so. A reported 1, 182 persons or organizations, representing fifty-four countries, registered for the 16 th IGC and thirty-four countries sent 141 official delegates. Of the total number of registrants, 665 actually attended the meeting; 500 came from the USA; and fifteen had participated in the 5 th IGC. The 16 th Meeting convened in the U.S. Chamber of Commerce Building from 22 to 29 July. The eighteen half-day scientific sections-orogenesis (four), major divisions of the Paleozoic (three), miscellaneous (three), batholiths and related intrusives (two), arid-region geomorphic processes and products (one), fossil man and contemporary faunas (one), geology of copper and other ore deposits (one), geology of petroleum (one), measuring geologic time (one), and zonal relations of metalliferous deposits (one)-included 166 papers, of which fifty (including several of the key contributions) appeared only by title. The Geological Society of Washington, the National Academy of Sciences, and the U.S. Bureau of Mines hosted or contributed to evening presentations or receptions. Twenty-eight of the 16 th IGC's thirty new guidebooks and one new USGS Bulletin aided eight pre-meeting, seven during-meeting, and four post-meeting field trips of local, regional, or national scope. The remaining two new guidebooks outlined the USA's structural geology and its stratigraphic nomenclature. The 16 th IGC published a two-volume monograph on the world's copper resources (1935) and a two-volume report of its proceedings (1936).

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Taxonomic evaluation of the three “type” specimens of the fringe-footed shrew, Sorex fimbripes Bachman, 1837 (Mammalia: Soricidae) and recommended nomenclatural status of the name

John Bachman (1837:391) described the “fringe-footed shrew,” Sorex fimbripes Bachman, 1837, in his landmark monograph on the North American Soricidae (Mammalia: Eulipotyphla), in which he recognized 13 uniquely New World species. Characters he attributed to S. fimbripes resulted in its being interpreted as a tiny, semi-aquatic species and contributed to the complexity of its subsequent taxonomic history. The status and location of the holotype, which should aid in resolving questions about the nature of S. fimbripes, instead have added to the confusion. Originally studied by Bachman in South Carolina, the holotype was later thought to have been identified in the Academy of Natural Sciences of Philadelphia (ANSP), and it is currently considered to be in the National Museum of Natural History (USNM), Washington, D.C. To clarify the identity of the species and its holotype, I compared descriptions of the holotype and the ANSP type with the USNM specimen and with eight species of eastern North American shrews. I conclude that the three accounts of S. fimbripes refer to three different specimens and that the holotype was probably destroyed during the American Civil War. Bachman's S. fimbripes was most likely equivalent to S. cinereus Kerr, 1792, S. fontinalis Hollister, 1911, or S. fumeus Miller, 1895, but without the holotype, its identity cannot be determined definitively, and the name is a nomen dubium.

Proceedings of the Biological Society of Washingto↗

Test and calibration of the Digital World-Wide Standardized Seismograph

During the past decade there has been steady progress in the modernization of the global seismograph network operated by the U.S. Geological Survey (USGS). The World-Wide Standardized Seismograph Network (WWSSN) has been augmented by new stations with advanced instrumentation, including the Seismic Research Observatories (SRO) and the modified High-Gain Long-Period (ASRO) stations. One goal in the modernization effort has been to improve signal resolution in the long-period band. A second goal has been to generate a global digital data base to support contemporary computer-based analysis and research. In 1976, a Panel on Seismograph Networks was established by the Committee on Seismology of the National Academy of Sciences to review progress in network seismology and recommend actions that would lead to an improved global data base for seismology. One recommendation in the Panel report (Engdahl, 1977) called for upgrading selected WWSSN stations by the installation of digital recorders. This was viewed as an economical way of expanding the digital network, which had proven itself to be a very promising new tool for earthquake and explosion research. Funds for the development and assembly of 15 digital recorders were provided to the USGS by the Defense Advanced Research Projects Agency and an ad Inoc panel of scientists was convened by the Committee on Seismology to advise the USGS on the selection of stations to be upgraded and on data recording requirements, A total of 19 digital World-Wide Standardized Seismograph (DWWSS) systems will be operational when all are installed. The additional systems were made available through purchase by the USGS and other organizations; for example, the University of Bergen purchased and installed a DWWSS-type recorder and agreed to furnish the USGS with the data. A list of operational and planned DWWSS network stations is given in Table 1.1. As one might expect, the digital recorder turned out to be somewhat more sophisticated than the original concept. It was decided to record three components of long-period data continuously, three components of intermediateperiod data in an event mode, and the vertical-component short-period data in and event mode (with the capability of adding short-period horizontal channels in the future). Special amplifiers were developed for use with the WWSS seismometers, and a 16-bit fixed-point analog-to-digital converter was chosen to provide increased resolution (as opposed to a 16-bit gain-ranged encoder). The microprocessor-based digital recording systems were developed and assembled at the USGS Albuquerque Seismological Laboratory (ASL) and ASL-based technicians began installation at WWSSN stations in 1980. The current and proposed locations of the DWWSSN stations, together with other stations in the Global Digital Seismograph Network (GDSN), are shown on the map in Figure 1.1. A system was operated at Albuquerque for about 18 months, serving as a test bed for evaluation studies. Although the network hardware has been available for some time, the installation of the DWWSSN has proceeded slowly. The National Science Foundation supported installation of six stations and the USGS is funding installation of most of the others; however, the network completion date is conjectural because of funding uncertainties. The DWWSSN stations are supported with supplies and technical assistance from ASL (subject to availability of funds). Data recorded on magnetic tapes are mailed to ASL where they are reviewed for quality, then merged with other GDSN station data on the network-day tapes. Hoffman (1980) provides a description of the network-day tape format. Zirbes and Buland (1981) have developed and published user software for reading and interpreting the day tapes. This report will serve several purposes. One is to provide nominal system transfer functions and calibration information that are needed in the analysis of DWWSSN data. A second purpose is to report on an evaluation of operating characteristics (calibration stability, noise levels, and linearity) that may limit the usefulness of the data and to determine if modifications may be needed to improve the data. It is not an exhaustive study in this respect. We continue to depend mostly on data user feedback to point out deficiencies and we solicit comments whenever anomalies are observed in the data.

Open-File Report↗

Proceedings of the 25th Himalaya-Karakoram-Tibet Workshop

For a quarter of a century the Himalayan-Karakoram-Tibet (HKT) Workshop has provided scientists studying the India-Asia collision system a wonderful opportunity for workshop-style discussion with colleagues working in this region. In 2010, HKT returns to North America for the first time since 1996. The 25th international workshop is held from June 7 to10 at San Francisco State University, California. The international community was invited to contribute scientific papers to the workshop, on all aspects of geoscience research in the geographic area of the Tibetan Plateau and its bounding ranges and basins, from basic mapping to geochemical and isotopic analyses to large-scale geophysical imaging experiments. In recognition of the involvement of U.S. Geological Survey (USGS) scientists in a wide range of these activities, the USGS agreed to publish the extended abstracts of the numerous components of HKT-25 as an online Open-File Report, thereby ensuring the wide availability and distribution of these abstracts, particularly in the HKT countries from which many active workers are precluded by cost from attending international meetings. In addition to the workshop characterized by contributed presentations, participants were invited to attend a pre-meeting field trip from the Coast Ranges to the Sierra Nevada, to allow the international group to consider how the tectonic elements of the Pacific margin compare to those of the Himalayan belt. Following the workshop, the National Science Foundation (NSF) sponsored a workshop on the 'Future directions for NSF-sponsored geoscience research in the Himalaya/Tibet' intended to provide NSF Program Directors with a clear statement and vision of community goals for the future, including the scientific progress we can expect if NSF continues its support of projects in this geographic region, and to identify which key geoscience problems and processes are best addressed in the Himalaya and Tibet, what key datasets are needed, and how NSF can best support the evolving need for interdisciplinary investigations. This workshop also has clear societal relevance. Recent earthquakes have brought international attention to active tectonics and earthquake hazards in the HKT region. Prominent examples include the Mw 7.8 Kokoxili (Qinghai, China) earthquake of 2001, the Mw 7.6 Kashmir (Pakistan) earthquake of 2005, the Mw 7.9 Wenchuan (Sichuan, China) earthquake of 2008, and this year the Mw 6.9 Yushu (Qinghai, China) earthquake. Geological and geophysical field work conducted both before these earthquakes, as well as in response to them, has helped to define the active faults and regional tectonics in the HKT region. The research presented at this workshop provides the framework necessary for improved seismic hazard assessments in this region. The organizers gratefully acknowledge the support of NSF's Continental Dynamics Program and its Office of International Science and Engineering, through award EAR-0965796. We thank San Francisco State University's Sheldon Axler, Dean of the College of Science and Engineering, and Toby Garfield, Director of the Romberg Tiburon Center, for use of their conference facilities; and the Department of Geosciences, particularly Deb Shulman and Miriam Knof, for administrative support. The California Academy of Sciences generously hosted a reception for visiting delegates, and Brad Ritts (Chevron Exploration Technology Company), Todd Greene (California State University, Chico) and John Shervais (Utah State University) together co-led the pre-conference field trip. Technical editing of this volume was led by Roxanne Renedo (U.S. Geological Survey) with assistance from Margaret Milia (Stanford University). We are grateful to the U.S. Geological Survey (USGS) Earthquake Hazards Program and the USGS Menlo Park (California) Publishing Service Center for making this online report possible.

Open-File Report↗