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Stratigraphic revision of the Cooper Group and the Chandler and Edisto Formations in the Coastal Plain of South Carolina

No abstract available. 
Authors
Robert E. Weems, Barry Albright, Laurel M. Bybell, David J. Cicimurri, Lucy E. Edwards, W. Burleigh Harris, William C. Lewis, Jason E. Osborne, Albert E. Sanders, Jean Self-Trail

Evidence for an ice shelf covering the central Arctic Ocean during the penultimate glaciation

The hypothesis of a km-thick ice shelf covering the entire Arctic Ocean during peak glacial conditions was proposed nearly half a century ago. Floating ice shelves preserve few direct traces after their disappearance, making reconstructions difficult. Seafloor imprints of ice shelves should, however, exist where ice grounded along their flow paths. Here we present new evidence of ice-shelf groundi
Authors
Martin Jakobsson, Johan Nilsson, Leif G. Anderson, Jan Backman, Goran Bjork, Thomas M. Cronin, Nina Kirchner, Andrey Koshurnikov, Larry Mayer, Riko Noormets, Matthew O'Regan, Christian Stranne, Roman Ananiev, Natalia Barrientos Macho, Dennis Cherniykh, Helen Coxall, Bjorn Eriksson, Tom Floden, Laura Gemery, Orjan Gustafsson, Kevin Jerram, Carina Johansson, Alexey Khortov, Rezwan Mohammad, Igor Semiletov

Metaultramafic schists and dismembered ophiolites of the Ashe Metamorphic Suite of northwestern North Carolina, USA

Metaultramafic rocks (MUR) in the Ashe Metamorphic Suite (AMS) of northwestern North Carolina include quartz ± feldspar-bearing QF-amphibolites and quartz-deficient, locally talc-, chlorite-, and/or Mg-amphibole-bearing TC-amphibolites. Some workers divide TC-amphibolites into Todd and Edmonds types, based on mineral and geochemical differences, and we provisionally add a third type – olivine ± py
Authors
Loren A. Raymond, Arthur J. Merschat, R. Kelly Vance

Geology of the Mount Rogers area, revisited: Evidence of Neoproterozoic continental rifting, glaciation, and the opening and closing of the Iapetus ocean, Blue Ridge, VA–NC–TN

Recent field and geochronological studies in eight 7.5-minute quadrangles near Mount Rogers in Virginia, North Carolina and Tennessee recognize important stratigraphic and structural relationships for the Neoproterozoic Mount Rogers and Konnarock formations, the northeast end of the Mountain City window, the separation of Mesoproterozoic rocks of the Blue Ridge into three age groups, and timing an

Authors
Arthur J. Merschat, C. Scott Southworth, Christopher S. Holm-Denoma, Ryan J. McAleer

Structural geometry of the Valley and Ridge and Plateaus provinces

The Valley and Ridge physiographic province comprises the area between the Blue Ridge province on the east and the Appalachian Plateau province on the west. The province consists of Paleozoic carbonate and clastic rocks that were folded and thrust faulted during the Alleghanian orogeny. The Appalachian Plateau province consists of mostly flat lying to gently dipping upper Paleozoic rocks, with the
Authors
Mark A. Evans, Randall C. Orndorff, William S. Henika

Paleogeographic implications of Late Miocene lacustrine and nonmarine evaporite deposits in the Lake Mead region: Immediate precursors to the Colorado River

Thick late Miocene nonmarine evaporite (mainly halite and gypsum) and related lacustrine limestone deposits compose the upper basin fill in half grabens within the Lake Mead region of the Basin and Range Province directly west of the Colorado Plateau in southern Nevada and northwestern Arizona. Regional relations and geochronologic data indicate that these deposits are late synextensional to poste
Authors
James E. Faulds, Charlotte Schreiber, Victoria E. Langenheim, Nicholas H. Hinz, Tom Shaw, Matthew T. Heizler, Michael E Perkins, Mohammed El Tabakh, Michael J. Kunk

Reply Zalasiewicz et al. comment

No abstract available.
Authors
Stanley C. Finney, Lucy E. Edwards

Glacial Lake Hitchcock and the sea: Fieldtrip Guidebook for the 78th Annual Reunion of the Northeast Friends of the Pleistocene

The fieldtrip will demonstrate the evidence for a close connection of Lake Hitchcock levels with lake levels and the position of sea level in Long Island Sound via a channel cut into glacial lake deposits in the lower Connecticut River valley, which issuperposed on a bedrock ridge at the mouth of the Connecticut River. On the trip we will explain important offshore features like an extensive  ‐40‐
Authors
Janet Radway Stone, J.C. Ridge, Ralph S. Lewis, Mary L. DiGiacomo-Cohen

Early Mesozoic geology in Virginia

No abstract available.
Authors
Joseph P. Smoot

Loamy, two-storied soils on the outwash plains of southwestern lower Michigan: Pedoturbation of loess with the underlying sand

Soils on many of the outwash plains in southwestern Michigan have loamy upper profiles, despite being underlain by sand-textured outwash. The origin of this upper, loamy material has long been unknown. The purpose of this study is to analyze the spatio-textural characteristics of these loamy-textured sediments to ascertain their origin(s). The textural curves of this material have distinct bimodal
Authors
Michael D. Luehmann, Brad G. Peter, Christopher B. Connallon, Randall J. Schaetzl, Samuel J. Smidt, Wei Liu, Kevin A. Kincare, Toni A. Walkowiak, Elin Thorlund, Marie S. Holler

Petrology and tectonic history of the Green Bay Schist, Portmore, St. Catherine Parish, Jamaica

There are three occurrences of medium- to high-grade metamorphic rocks in Jamaica: amphibolite facies Westphalia Schist, blueschist/greenschist facies Mt. Hibernia Schist, and the hitherto poorly characterized amphibolite facies Green Bay Schist. New trace element data and thermodynamic calculations show that Green Bay Schist is closely related to Westphalia Schist. The protoliths for both are ver

Authors
Richard N. Abbott, David P. West, Betsy R. Bandy, Ryan J. McAleer

Awell-preserved conodont fauna from the Pennsylvanian Excello Shale of Iowa, U. S. A.

A superbly preserved discrete element conodont fauna has been recovered from carbonate concretions from the upper Desmoinesian (Pennsylvanian) Excello Shale at two localities in south-central Iowa. The multielement apparatuses for Gondolella wardlawi (new species), Idiognathodus acutus, Idioprioniodus conjunctus, and Neognathodus roundyi are reconstructed. Rare specimens of Idiognathodus tuberis (
Authors
Merlynd K. Nestell, Bruce R. Wardlaw, John P. Pope