Publications
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Geochronologic age constraints on tectonostratigraphic units of the central Virginia Piedmont, USA
New geologic mapping coupled with uranium-lead (U-Pb) zircon geochronology (sensitive high-resolution ion microprobe-reverse geometry [SHRIMP-RG] and laser ablation-inductively coupled plasma-mass spectrometry [LA-ICP-MS]) analyses of 10 samples, provides new constraints on the tectonostratigraphic framework of the central Virginia Piedmont. Detrital zircon analysis confirms that the Silurian-Devo
Authors
Mark W. Carter, Ryan J. McAleer, Christopher S. Holm-Denoma, David B. Spears, Sean P. Regan, William C. Burton, Nick H. Evans
Carbon release through abrupt permafrost thaw
The permafrost zone is expected to be a substantial carbon source to the atmosphere, yet large-scale models currently only
simulate gradual changes in seasonally thawed soil. Abrupt thaw will probably occur in
Authors
Merritt R. Turetsky, Benjamin W. Abbott, Miriam C. Jones, Katey Walter Anthony, David Olefeldt, Edward A. Schuur, Guido Grosse, Peter Kuhry, Gustaf Hugelius, Charles Koven, David M. Lawrence, Carolyn Gibson, A. Britta K. Sannel, A.D. McGuire
Estimating late 19th century hydrology in the Greater Everglades Ecosystem: An integration of paleoecologic data and models
Determining hydrologic conditions prior to instrumental records is a challenge for restoration of freshwater ecosystems worldwide. Paleoecologic data provide this information on past conditions and when these data are used to adjust hydrologic models, allow conditions to be hindcast that may not be directly estimated from the paleo-data alone. In this context, the paleo-data provide real-world es
Authors
Frank E. Marshall, Christopher E. Bernhardt, G. Lynn Wingard
Marine latitudinal diversity gradients, niche conservatism and out of the tropics and Arctic: Climatic sensitivity of small organisms
AimThe latitudinal diversity gradient (LDG) is a consequence of evolutionary and ecological mechanisms acting over long history, and thus is best investigated with organisms that have rich fossil records. However, combined neontological‐palaeontological investigations are mostly limited to large, shelled invertebrates, which keeps our mechanistic understanding of LDGs in its infancy. This paper ai
Authors
Wing‐Tung Ruby Chiu, Moriaki Yasuhara, Thomas M. Cronin, Gene Hunt, Laura Gemery, Chih‐Lin Wei
Planktic foraminiferal test size and weight response to the late Pliocene environment
Atmospheric carbon dioxide (pCO2atm) is impacting the ocean and marine organisms directly via changes in carbonate chemistry and indirectly via a range of changes in physical parameters most dominantly temperature. To assess potential impacts of climate change on carbonate production in the open ocean, we measured size and weight of planktic foraminifers during the late Pliocene at pCO2atm concent
Authors
Chloe L. Todd, Daniela N. Schmidt, Marci M. Robinson, S. de Schepper
Major-element compositional data and thermal data for drill core from Kīlauea Iki lava lake, plus analyses of glasses from scoria of the 1959 summit eruption of Kīlauea Volcano, Hawaii
This report presents electron microprobe data on glasses and selected crystalline phases from Kīlauea Iki lava lake and glasses from the 1959 summit eruption of Kīlauea Volcano, Hawaii. Some of these data have been published previously, but the complete set has not been published before. In addition, this report includes electron microprobe data for phases in melting experiments reported earlier,
Authors
Rosalind Tuthill Helz
Quaternary eolian dunes and sand sheets in inland locations of the Atlantic Coastal Plain Province, USA
Quaternary eolian dunes and sand sheets that are stabilized by vegetation are present throughout many inland locations of the Atlantic Coastal Plain province (USA). These locations include river valleys, the Carolina Sandhills region, adjacent to Carolina Bays, and upland areas of the northern coastal plain. The eolian dunes are primarily parabolic in river valleys and in upland areas of the north
Authors
Christopher S. Swezey
A transect through Vermont's most famous volcano - Mount Ascutney
The Cretaceous Ascutney Mountain igneous complex affords a classic exposure of the White Mountain Igneous Suite. Often called Vermont’s most famous volcano, Mount Ascutney (elev. 3,144 feet, 958 m) stands as a prominent monadnock in the Connecticut River Valley. The mountain often serves as an inspirational landmark, as it does when viewed from locations throughout the valley including the Saint-
Authors
Gregory J. Walsh, Brooks P. Proctor, Karri R. Sicard, Peter M. Valley
Geochronology of the Oliverian Plutonic Suite and the Ammonoosuc Volcanics in the Bronson Hill arc: Western New Hampshire, USA
U-Pb zircon geochronology by sensitive high-resolution ion microprobe–reverse geometry (SHRIMP-RG) on 11 plutonic rocks and two volcanic rocks from the Bronson Hill arc in western New Hampshire yielded Early to Late Ordovician ages ranging from 475 to 445 Ma. Ages from Oliverian Plutonic Suite rocks that intrude a largely mafic lower section of the Ammonoosuc Volcanics ranged from 474.8 ± 5.2 to 4
Authors
Peter M. Valley, Gregory J. Walsh, Arthur J. Merschat, Ryan J. McAleer
Geochemistry and geophysics of iron oxide-apatite deposits and associated waste piles with implications for potential rare earth element resources from ore and historic mine waste in the eastern Adirondack Highlands, New York, USA
The iron oxide-apatite (IOA) deposits of the eastern Adirondack Highlands, New York, are historical high-grade magnetite mines that contain variable concentrations of rare earth element (REE)-bearing apatite crystals. The majority of the deposits are hosted within sodically altered Lyon Mountain granite gneiss, although some deposits occur within paragneiss, gabbro, anorthosite, or potassically al
Authors
Ryan Taylor, Anjana K. Shah, Gregory J. Walsh, Cliff D. Taylor
Impacts of Hurricane Irma on Florida Bay Islands, Everglades National Park, U.S.A.
Hurricane Irma made landfall in south Florida, USA, on September 10, 2017 as a category 4 storm. In January 2018, fieldwork was conducted on four previously (2014) sampled islands in Florida Bay, Everglades National Park to examine changes between 2014 and 2018. The objectives were to determine if the net impact of the storm was gain or loss of island landmass and/or elevation; observe and quantif
Authors
G. Lynn Wingard, Sarah E. Bergstresser, Bethany Stackhouse, Miriam Jones, Marci E. Marot, Kristen Hoefke, Andre Daniels, Katherine Keller