Publications
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The planktonic foraminiferal response to the Paleocene-Eocene thermal maximum on the Atlantic coastal plain
Planktonic foraminiferal assemblages in two cores from Maryland and New Jersey show evidence for significant changes in surface ocean habitats on the continental shelf during the Paleocene-Eocene Thermal Maximum (PETM). At both sites, significant assemblage shifts occur immediately before the onset of the event. These changes include the appearance of abundant triserial/biserial species as well as
Authors
Caitlin M. Livsey, Tali Babila, Marci M. Robinson, Timothy J. Bralower
Geographic attribution of soils using probabilistic modeling of GIS data for forensic search efforts
Examinations of soil traces associated with forensic evidence can be used to narrow potential source area(s) by characterizing features of the trace soil assemblage, some of which are limited to specific regions. Soil characteristics may be used to infer the likelihoods of the soil trace being derived from distinct areas within digital maps, including both maps of discrete classes such as formatio
Authors
Libby A Stern, Jodi B Webb, Debra A. Willard, Christopher E. Bernhardt, David Korejwo, Maureen Bottrell, Garrett McMahon, nancy McMillan, Jared Schuetter, Patrick Wheatley, Jack Hieptas
North Atlantic midlatitude surface-circulation changes through the Plio-Pleistocene intensification of northern hemisphere glaciation
The North Atlantic Current (NAC) transports warm salty water to high northern latitudes, with important repercussions for ocean circulation and global climate. A southward displacement of the NAC and Subarctic Front, which separate subpolar and subtropical water masses, is widely suggested for the Last Glacial Maximum (LGM) and may have acted as a positive feedback in glacial expansion at this tim
Authors
Clara T. Bolton, Ian Bailey, Oliver Friedrich, Kazuyo Tachikawa, Thibault de Garidel‐Thoron, Laurence Vidal, Corinne Sonzogni, Gianluca Marino, Eelco J. Rohling, Marci M. Robinson, Magali Ermini, Mirjam Koch, Matthew J. Cooper, Paul A. Wilson
Chesapeake Bay impact structure—Development of "brim" sedimentation in a multilayered marine target
The late Eocene Chesapeake Bay impact structure was formed in a multilayered target of seawater underlain sequentially by a sediment layer and a rock layer in a continental-shelf environment. Impact effects in the “brim” (annular trough) surrounding and adjacent to the transient crater, between the transient crater rim and the outer margin, primarily were limited to the target-sediment layer. Anal
Authors
Henning Dypvik, Gregory Gohn, Lucy Edwards, J. Wright Horton,, David Powars, Ronald Litwin
Evidence for shelf acidification during the onset of the Paleocene-Eocene Thermal Maximum
A transect of paleoshelf cores from Maryland and New Jersey contains a ~0.19 m to 1.61 m thick interval with reduced percentages of carbonate during the onset of the Paleocene-Eocene Thermal Maximum (PETM). Outer paleoshelf cores are barren of nannofossils and correspond to two minor disconformities. Middle paleoshelf cores contain a mixture of samples devoid of nannofossils and those with rare
Authors
Timothy J. Bralower, Lee R. Kump, Marci M. Robinson, Jean Self-Trail, Shelby L. Lyons, Tali Babila, Edward Ballaron, Katherine H. Freeman, Elizabeth A. Hajek, William Rush, James C. Zachos
The Central African Republic Diamond Database—A geodatabase of archival diamond occurrences and areas of recent artisanal and small-scale diamond mining
The alluvial diamond deposits of the Central African Republic (CAR) are mined almost exclusively by way of informal artisanal and small-scale mining (ASM) methods. ASM sites range in diameter from a few meters to 30 meters or more, and are typically excavated by crews of diggers using hand tools, sieves, and jigs. CAR’s reported annual production has ranged from 300,000 to 470,000 carats over the
Authors
Jessica D. DeWitt, Peter G. Chirico, Sarah E. Bergstresser, Inga E. Clark
The significance of dinoflagellates in the Miocene Choptank Formation beneath the Midlothian gravels in the southeastern Virginia Piedmont
The Fall Line (formally "Tidewater Fall Line") separates the more resistant igneous, metamorphic, and consolidated sedimentary rocks of the Piedmont from the typically unconsolidated deposits of the Coastal Plain of Virginia. Widespread but now discontinuous patches of a deeply weathered sand and gravel are found west of the Fall Line, capping the highest hilltops. Near the community of Midlothian
Authors
Lucy E. Edwards, Robert E. Weems, Mark W. Carter, David Spears, David S. Powars
PRISM marine sites—The history of PRISM sea surface temperature estimation
For more than three decades, the U.S. Geological Survey (USGS) Pliocene Research, Interpretation and Synoptic Mapping (PRISM) Project has compiled paleoenvironmental data with the goal of reconstructing global conditions during the warm interval in the middle of the Piacenzian Age of the Pliocene Epoch (about 3.3 to 3.0 million years ago). Because this is the most recent interval of time in which
Authors
Marci M. Robinson, Harry J. Dowsett, Kevin M. Foley, Christina R. Riesselman
Latitudinal limits to the predicted increase of the peatland carbon sink with warming
The carbon sink potential of peatlands depends on the balance of carbon uptake by plants and microbial decomposition. The rates of both these processes will increase with warming but it remains unclear which will dominate the global peatland response. Here we examine the global relationship between peatland carbon accumulation rates during the last millennium and planetary-scale climate space. A p
Authors
Angela Gallego-Sala, Dan Charman, Simon Brewer, Sue Page, I. Colin Prentice, Pierre Friedlingstein, Steven Morley, Matthew Amesbury, David Beilman, Svante Bjorck, Tatiana Blyakharchuk, Christopher Bochicchio, Robert K Booth, Joan Bunbury, Philip Camill, Donna Carless, Rodney A. Chimner, Michael Clifford, Elizabeth Cressey, Colin Courtney-Mustaphi, Francois De Vleeschouwer, Rixt de Jong, Barbara Fialkiawicz-Koziel, Sarah A Finkelstein, Michelle Garneau, Esther N. Githumbi, John Hribjlan, James Holmquist, Paul Hughes, Chris D. Jones, Miriam Jones, Edgar Karofeld, Eric S. Klein, Ulla Kokfelt, Atte Korhola, Terri Lacourse, Gael LeRoux, Mariusz Lamentowicz, David Large, Martin Lavoie, Julie Loisel, Helen MacKay, Glen M. MacDonald, Markku Makila, Gabriel Magnan, R. Marchant, Katarzyna Marcisz, Antonio Martinez-Cortizas, Charly Massa, Paul Mathijssen, Dmitri Mauquoy, Timothy Mighall, Fraser J.G. Mitchell, Patrick Moss, J. Nichols, P.O. Oksanen, L. Orme, Maara S. Packalen, Stephen Robinson, Thomas P. Roland, Nicole K. Sanderson, A. B. K. Sannel, Noemi Silva-Sanchez, Natasha Steinberg, Graeme T. Swindles, T. Edward Turner, Joanna Uglow, M. Valiranta, Simon van Bellen, Marjolein van der Linden, Guoping Wang, Zicheng Yu, Joana Zaragoza-Castells, Yan Zhao
Geologic map of the Timberville quadrangle, Virginia
This map of the Timberville 7.5-minute quadrangle in Rockingham and Shenandoah counties, Virginia shows the distribution of Paleozoic-age sedimentary rocks in map and cross-section. Surficial deposits including alluvium and colluvium are also shown. The characteristics of each map unit are described and a brief report discusses the stratigraphy, structure and mineral resources of the area.
Authors
Matthew J. Heller, Randall C. Orndorff, David A. Hubbard, Eugene K. Rader
Kinematic, deformational, and thermochronologic conditions along the Gossan Lead and Fries shear zones: Constraining the western-eastern Blue Ridge boundary in northwestern North Carolina
The fault boundary between the western and eastern Blue Ridge (WBR-EBR) in the southern Appalachians separates Mesoproterozoic basement rocks and their cover from Neoproterozoic to Paleozoic accreted rocks. Several northeast striking faults delineate the boundary, including the Gossan Lead shear zone in northwestern North Carolina. Varying tectonic interpretations of WBR-EBR boundary include a pre
Authors
Jamie S. F. Levine, Arthur J. Merschat, Ryan J. McAleer, G. Casale, K. R. Quillan, K. I. Fraser, T. G. BeDell
Divisions of geologic time—Major chronostratigraphic and geochronologic units
IntroductionEffective communication in the geosciences requires a consistent nomenclature for stratigraphic units and, especially, for divisions of geologic time. A geologic time scale is composed of standard stratigraphic divisions based on rock sequences and is calibrated in years.Geologists from the U.S. Geological Survey (USGS), State geological surveys, academia, and other organizations requi
Authors