Publications
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A revision of the Norian Conchostracan Zonation in North America and its implications for Late Triassic North American tectonic history A revision of the Norian Conchostracan Zonation in North America and its implications for Late Triassic North American tectonic history
Collections of Upper Triassic (Norian) conchostracans from the upper Cumnock and lower Sanford formations (North Carolina), Bull Run Formation (Virginia), Gettysburg Formation (Pennsylvania), Passaic Formation (New Jersey), Blomidon Formation (Nova Scotia), and Redonda Formation (New Mexico) have significantly expanded our knowledge of the Norian conchostracan faunas in these units...
Authors
Robert E. Weems, Spencer G. Lucas
Ordovician of Germany Valley, West Virginia Ordovician of Germany Valley, West Virginia
This trip will consist of stops at five locations (Fig. 1) that provide a detailed look at the strata in a major part of the Ordovician section in Germany Valley, Pendleton County, West Virginia. At these stops, we will highlight a varied sequence of carbonate and siliciclastic strata that accumulated during the Middle to Late Ordovician, and which record changes in depositional...
Authors
John T. Haynes, Keith E. Goggin, Randall C. Orndorff, Lisa R. Goggin
The 2011 Mineral, Virginia, earthquake and its significance for seismic hazards in eastern North America: overview and synthesis The 2011 Mineral, Virginia, earthquake and its significance for seismic hazards in eastern North America: overview and synthesis
The 23 August 2011 Mw (moment magnitude) 5.7 ± 0.1, Mineral, Virginia, earthquake was the largest and most damaging in the central and eastern United States since the 1886 Mw 6.8–7.0, Charleston, South Carolina, earthquake. Seismic data indicate that the earthquake rupture occurred on a southeast-dipping reverse fault and consisted of three subevents that progressed northeastward and...
Authors
J. Wright Horton, Martin C. Chapman, Russell A. Green
Preface Preface
This book grew out of a topical session on “Central Virginia Earthquakes of 2011: Geology, Geophysics, and Significance for Seismic Hazards in Eastern North America” at the 2012 The Geological Society of America (GSA) Annual Meeting in Charlotte, North Carolina (USA). It also benefitted from related sessions at other meetings. The goal of this volume, The 2011 Mineral, Virginia...
Authors
J. Wright Horton, Martin C. Chapman, Russell A. Green
Field trip guidebook for the post-meeting field trip: The Central Appalachians Field trip guidebook for the post-meeting field trip: The Central Appalachians
The lower Paleozoic rocks to be examined on this trip through the central Appalachians represent an extreme range of depositional environments. The lithofacies we will examine range from pelagic radiolarian chert and interbedded mudstone that originated on the deep floor of the Iapetus Ocean, through mud cracked supratidal dolomitic laminites that formed during episodes of emergence of...
Authors
John F. Taylor, James D. Loch, G. Robert Ganis, John E. Repetski, Charles E. Mitchell, Gale C. Blackmer, David K. Brezinski, Daniel Goldman, Randall C. Orndorff, Bryan K. Sell
Cambrian–Ordovician of the central Appalachians:Correlations and event stratigraphy of carbonate platform andadjacent deep-water deposits Cambrian–Ordovician of the central Appalachians:Correlations and event stratigraphy of carbonate platform andadjacent deep-water deposits
This trip seeks to illustrate the succession of Cambrian and Ordovician facies deposited within the Pennsylvania and Maryland portion of the Great American Carbonate Bank. From the Early Cambrian (Dyeran) through Late Ordovician (Turinan), the Laurentian paleocontinent was rimmed by an extensive carbonate platform. During this protracted period of time, a succession of carbonate rock...
Authors
David K. Brezinski, John F. Taylor, John E. Repetski, James D. Loch
Early Permian conodont fauna and stratigraphy of the Garden Valley Formation, Eureka County, Nevada Early Permian conodont fauna and stratigraphy of the Garden Valley Formation, Eureka County, Nevada
The lower part of the Garden Valley Formation yields two distinct conodont faunas. One of late Asselian age dominated by Mesogondolella and Streptognathodus and one of Artinskian age dominated by Sweetognathus with Mesogondolella. The Asselian fauna contains the same species as those found in the type area of the Asselian in the southern Urals including Mesogondolella dentiseparata...
Authors
Bruce R. Wardlaw, Dora M. Gallegos, Valery V. Chernykh, Walter S. Snyder
A semi-automated tool for reducing the creation of false closed depressions from a filled LIDAR-derived digital elevation model A semi-automated tool for reducing the creation of false closed depressions from a filled LIDAR-derived digital elevation model
Closed depressions on the land surface can be identified by ‘filling’ a digital elevation model (DEM) and subtracting the filled model from the original DEM. However, automated methods suffer from artificial ‘dams’ where surface streams cross under bridges and through culverts. Removal of these false depressions from an elevation model is difficult due to the lack of bridge and culvert...
Authors
John Wall, Daniel H. Doctor, Silvia Terziotti
Karst of the Mid-Atlantic region in Maryland, West Virginia, and Virginia Karst of the Mid-Atlantic region in Maryland, West Virginia, and Virginia
The Mid-Atlantic region hosts some of the most mature karst landscapes in North America, developed in highly deformed rocks within the Piedmont and Valley and Ridge physiographic provinces. This guide describes a three-day excursion to examine karst development in various carbonate rocks by following Interstate 70 west from Baltimore across the eastern Piedmont, across the Frederick...
Authors
Daniel H. Doctor, David J. Weary, David K. Brezinski, Randall C. Orndorff, Lawrence E. Spangler
Continuous monitoring of meteorological conditions and movement of a deep-seated, persistently moving rockslide along Interstate Route 79 near Pittsburgh Continuous monitoring of meteorological conditions and movement of a deep-seated, persistently moving rockslide along Interstate Route 79 near Pittsburgh
A large inventory of landslides exists for Allegheny County, Pa., and historical movement of manyof these has resulted in considerable damage to property, roads, and infrastructure. Along InterstateRoute 79, a subset of the landslide inventory includes deep-seated rockslides, two of which reactivatedduring construction of the highway in the late 1960s (Gray and others, 2011). Following...
Authors
Francis Ashland, Helen L. Delano
Cenozoic stratigraphy and structure of the Chesapeake Bay region Cenozoic stratigraphy and structure of the Chesapeake Bay region
The Salisbury embayment is a broad tectonic downwarp that is filled by generally seaward-thickening, wedge-shaped deposits of the central Atlantic Coastal Plain. Our two-day field trip will take us to the western side of this embayment from the Fall Zone in Washington, D.C., to some of the bluffs along Aquia Creek and the Potomac River in Virginia, and then to the Calvert Cliffs on the...
Authors
David S. Powars, Lucy E. Edwards, Susan M. Kidwell, J. Stephen Schindler
Geologic framework and evidence for neotectonism in the epicentral area of the 2011 Mineral, Virginia, earthquake Geologic framework and evidence for neotectonism in the epicentral area of the 2011 Mineral, Virginia, earthquake
The epicenters of the main shock and associated aftershocks of the 2011 moment magnitude, Mw 5.8 Mineral, Virginia (USA), earthquake, and the updip projection of the possible fault plane that triggered the quakes, are contained in the areas of 2 adjoining 7.5′ quadrangles in the central Virginia Piedmont. These quadrangles have therefore been the focus of concentrated geologic study in...
Authors
William C. Burton, Richard W. Harrison, David B. Spears, Nicholas H. Evans, Shannon A. Mahan