Publications
Filter Total Items: 880
Changing amounts and sources of moisture in the U.S. southwest since the Last Glacial Maximum in response to global climate change Changing amounts and sources of moisture in the U.S. southwest since the Last Glacial Maximum in response to global climate change
The U.S. southwest has a limited water supply and is predicted to become drier in the 21st century. An improved understanding of factors controlling moisture sources and availability is aided by reconstruction of past responses to global climate change. New stable isotope and growth-rate records for a central Texas speleothem indicate a strong influence of Gulf of Mexico (GoM) moisture...
Authors
Weimin Feng, Benjamin Hardt, Jay L. Banner, Kevin Meyer, Eric James, MaryLynn Musgrove, R. Lawrence Edwards, Hai Cheng, Angela Min
Interagency partnership to assess and restore a degraded urban riverine wetland: Dyke Marsh Wildlife Preserve, Virginia Interagency partnership to assess and restore a degraded urban riverine wetland: Dyke Marsh Wildlife Preserve, Virginia
The narrow-leaved cattail wetland known as Dyke Marsh formally became a land holding of George Washington Memorial Parkway (GWMP, a unit of the national park system) in 1959, along with a congressional directive to honor a newly-let 30-year commercial sand and gravel dredge-mining lease at the site. Dredging continued until 1974 when Public Law 93-251 called for the National Park Service...
Authors
Brent Steury, Ronald Litwin, Erik Oberg, Joseph Smoot, Milan Pavich, Geoffrey Sanders, Vincent Santucci
A methodological toolkit for field assessments of artisanally mined alluvial diamond deposits A methodological toolkit for field assessments of artisanally mined alluvial diamond deposits
This toolkit provides a standardized checklist of critical issues relevant to artisanal mining-related field research. An integrated sociophysical geographic approach to collecting data at artisanal mine sites is outlined. The implementation and results of a multistakeholder approach to data collection, carried out in the assessment of Guinea’s artisanally mined diamond deposits, also...
Authors
Peter G. Chirico, Katherine C. Malpeli
Surficial geologic map of the Charleston region, Berkeley, Charleston, Colleton, Dorchester, and Georgetown Counties, South Carolina Surficial geologic map of the Charleston region, Berkeley, Charleston, Colleton, Dorchester, and Georgetown Counties, South Carolina
This map portrays the surface and shallow subsurface geology of the greater Charleston, S.C. region east of 80°30′ west and south of 33°15′ north. The region covers the entirety of Charleston County and portions of Berkeley, Colleton, Dorchester, and Georgetown Counties. Units locally exposed at the surface range in age from middle Eocene to Holocene, but most of the area is covered by...
Authors
Robert Weems, William C. Lewis, Earl Lemon
A database and synthesis of northern peatland soil properties and Holocene carbon and nitrogen accumulation A database and synthesis of northern peatland soil properties and Holocene carbon and nitrogen accumulation
Here, we present results from the most comprehensive compilation of Holocene peat soil properties with associated carbon and nitrogen accumulation rates for northern peatlands. Our database consists of 268 peat cores from 215 sites located north of 45°N. It encompasses regions within which peat carbon data have only recently become available, such as the West Siberia Lowlands, the Hudson...
Authors
Rebecca Loiselle, Zicheng Yu, David Beilman, Philip Camill, Jukka Alm, Matthew Amesbury, David Anderson, Sofia Andersson, Christopher Bochicchio, Keith Barber, Lisa Belyea, Joan Bunbury, Frank Chambers, Dan Charman, Francois De Vleeschouwer, Barbara Fialkiawicz-Koziel, Sarah A Finkelstein, Mariusz Galka, Michelle Garneau, Dan Hammarlund, William Hinchcliffe, James Holmquist, Paul Hughes, Miriam Jones, Eric Klein, Ulla Kokfelt, Atte Korhola, Peter Kuhry, Alexandre Lamarre, Mariusz Lamentowicz, David Large, Martin Lavoie, Glen MacDonald, Gabriel Magnan, Markku Makila, Gunnar Mallon, Paul Mathijssen, Dmitri Mauquoy, Julia McCarroll, Tim Moore, Jonathan Nichols, Benjamin O’Reilly, P.O. Oksanen, Maara Packalen, Dorothy Peteet, Pierre Richard, Stephen Robinson, T.M. Ronkainen, Mats Rundgren, A. Sannel, Charles Tarnocai, Tim Thom, Eeva-Stiina Tuittila, Merritt Turetsky, M. Valiranta, Marjolein van der Linden, Bas van Geel, Simon van Bellen, Dale Vitt, Yan Zhao, Weijian Zhou
A shift of thermokarst lakes from carbon sources to sinks during the Holocene epoch A shift of thermokarst lakes from carbon sources to sinks during the Holocene epoch
Thermokarst lakes formed across vast regions of Siberia and Alaska during the last deglaciation and are thought to be a net source of atmospheric methane and carbon dioxide during the Holocene epoch1,2,3,4. However, the same thermokarst lakes can also sequester carbon5, and it remains uncertain whether carbon uptake by thermokarst lakes can offset their greenhouse gas emissions. Here we...
Authors
K. M. Walter Anthony, S. Zimov, G. Grosse, Miriam Jones, P. Anthony, F. Chapin, J. Finlay, M. Mack, S. Davydov, P. Frenzel, S. Frolking
Calibration of a conodont apatite-based Ordovician 87Sr/86Sr curve to biostratigraphy and geochronology: Implications for stratigraphic resolution Calibration of a conodont apatite-based Ordovician 87Sr/86Sr curve to biostratigraphy and geochronology: Implications for stratigraphic resolution
The Ordovician 87Sr/86Sr isotope seawater curve is well established and shows a decreasing trend until the mid-Katian. However, uncertainties in calibration of this curve to biostratigraphy and geochronology have made it difficult to determine how the rates of 87Sr/86Sr decrease may have varied, which has implications for both the stratigraphic resolution possible using Sr isotope...
Authors
M. Saltzman, C. Edwards, S. Leslie, Gary S. Dwyer, J. Bauer, John Repetski, A. Harris, S. Bergstrom
A field trip guidebook to the type localities of Marland Billings' 1935 Paleozoic bedrock stratigraphy near Littleton, New Hampshire A field trip guidebook to the type localities of Marland Billings' 1935 Paleozoic bedrock stratigraphy near Littleton, New Hampshire
Marland Billings' classic paper published in 1937 in the Geological Society of America Bulletin established a succession of six stratigraphic units in rocks of low metamorphic grade near Littleton, New Hampshire. The two youngest units are fossiliferous in the area, with ages established at the time as “middle” Silurian and Early Devonian. Billings and students mapped the same...
Authors
Douglas W. Rankin, Mary Rankin
Karst geomorphology and hydrology of the Shenandoah Valley near Harrisonburg, Virginia Karst geomorphology and hydrology of the Shenandoah Valley near Harrisonburg, Virginia
The karst of the central Shenandoah Valley has characteristics of both shallow and deep phreatic formation. This field guide focuses on the region around Harrisonburg, Virginia, where a number of these karst features and their associated geologic context can be examined. Ancient, widespread alluvial deposits cover much of the carbonate bedrock on the western side of the valley, where...
Authors
Daniel Doctor, Wil Orndorff, Joel Maynard, Matthew J. Heller, Gerolamo Casile
Late Holocene vegetation, climate, and land-use impacts on carbon dynamics in the Florida Everglades Late Holocene vegetation, climate, and land-use impacts on carbon dynamics in the Florida Everglades
Tropical and subtropical peatlands are considered a significant carbon sink. The Florida Everglades includes 6000-km2 of peat-accumulating wetland; however, detailed carbon dynamics from different environments within the Everglades have not been extensively studied or compared. Here we present carbon accumulation rates from 13 cores and 4 different environments, including sawgrass ridges...
Authors
Miriam Jones, Christopher Bernhardt, Debra Willard
A deglacial and Holocene record of climate variability in south-central Alaska from stable oxygen isotopes and plant macrofossils in peat A deglacial and Holocene record of climate variability in south-central Alaska from stable oxygen isotopes and plant macrofossils in peat
We used stable oxygen isotopes derived from bulk peat (δ18OTOM), in conjunction with plant macrofossils and previously published carbon accumulation records, in a ∼14,500 cal yr BP peat core (HT Fen) from the Kenai lowlands in south-central Alaska to reconstruct the climate history of the area. We find that patterns are broadly consistent with those from lacustrine records across the...
Authors
Miriam Jones, Matthew J. Wooller, Dorothy Peteet
Can uncertainties in sea ice albedo reconcile patterns of data-model discord for the Pliocene and 20th/21st centuries? Can uncertainties in sea ice albedo reconcile patterns of data-model discord for the Pliocene and 20th/21st centuries?
General Circulation Model simulations of the mid-Pliocene warm period (mPWP, 3.264 to 3.025 Myr ago) currently underestimate the level of warming that proxy data suggest existed at high latitudes, with discrepancies of up to 11°C for sea surface temperature estimates and 17°C for surface air temperature estimates. Sea ice has a strong influence on high-latitude climates, partly due to...
Authors
Fergus Howell, Alan Haywood, Aisling Dolan, Harry Dowsett, Jane Francis, Daniel Hill, Steven Pickering, James Pope, Ulrich Salzmann, Bidget Wade