Florence Bascom Geoscience Center
Publications
The mighty Susquehanna—extreme floods in Eastern North America during the past two millennia
The hazards posed by infrequent major floods to communities along the Susquehanna River and the ecological health of Chesapeake Bay remain largely unconstrained due to the short length of streamgage records. Here we develop a history of high‐flow events on the Susquehanna River during the late Holocene from flood deposits contained in MD99‐2209, a...
Toomey, Michael; Cantwell, Meagan; Colman, Steven; Cronin, Thomas M.; Donnelly, Jeffrey P.; Giosan, Liviu; Heil, Clifford; Korty, Robert L.; Marot, Marci E.; Willard, Debra A. Paleocene–Eocene Thermal Maximum prolonged by fossil carbon oxidation
A hallmark of the rapid and massive release of carbon during the Palaeocene–Eocene Thermal Maximum is the global negative carbon isotope excursion. The delayed recovery of the carbon isotope excursion, however, indicates that CO2 inputs continued well after the initial rapid onset, although there is no consensus about the source of this...
Lyons, Shelby L.; Baczynski, Allison A.; Babila, Tali L.; Bralower, Timothy J.; Hajek, Elizabeth A.; Kump, Lee R.; Polites, Ellen G.; Self-Trail, Jean M.; Trampush, Sheila M.; Vornlocher, Jamie R.; Zachos, James C.; Freeman, Katherine H. 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...
Livsey, Caitlin M.; Babila, Tali; Robinson, Marci M.; Bralower, Timothy J. 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,...
Dypvik, Henning; Gohn, Gregory; Edwards, Lucy; Horton, J. Wright; Powars, David; Litwin, Ronald 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...
Bralower, Timothy J.; Kump, Lee R.; Robinson, Marci M.; Self-Trail, Jean M.; Lyons, Shelby L.; Babila, Tali; Ballaron, Edward; Freeman, Katherine H.; Hajek, Elizabeth A.; Rush, William; Zachos, James C. Appalachian Basin stratigraphy, tectonics, and eustasy from the Blue Ridge to the Allegheny Front, Virginia and West Virginia
This guide is from a two-day field trip in western Virginia and eastern West Virginia held before the 2015 Geological Society of America annual meeting in Baltimore, Maryland. The field trip examines exposures of Paleozoic sedimentary strata in the Appalachian Basin starting in the Blue Ridge physiographic province, going through the Valley and...
Haynes, John T.; Pitts, Alan D.; Doctor, Daniel H.; Diecchio, Richard J.; Blake, Mitchell B. The impact of late Holocene land-use change, climate variability, and sea-level rise on carbon storage in tidal freshwater wetlands on the southeastern United States Coastal Plain
This study examines Holocene impacts of changes in climate, land use, and sea-level rise (SLR) on sediment accretion, carbon accumulation rates (CAR), and vegetation along a transect of tidal freshwater forested wetlands (TFFW) to oligohaline marsh along the Waccamaw River, South Carolina (4 sites) and along the Savannah River, Georgia (4 sites)....
Jones, Miriam; Bernhardt, Christopher E.; Krauss, K.W.; Noe, Gregory B.
Surficial materials of Massachusetts—A 1:24,000-scale geologic map database
The surficial materials geologic map database defines the distribution of nonlithified earth materials at the land surface in the 189 7.5-minute, 1:24,000-scale quadrangles that cover the Commonwealth of Massachusetts (index map). Across the State, these materials range in thickness from a few feet to more than 500 feet (ft). In some places,...
Stone, Janet Radway; Stone, Byron D.; DiGiacomo-Cohen, Mary L.; Mabee, Stephen B. Ecological changes in the nannoplankton community across a shelf transect during the onset of the Paleocene-Eocene Thermal Maximum
Warming and other environmental changes during the Paleocene‐Eocene thermal maximum (PETM) led to profound shifts in the composition and structure of nannoplankton assemblages. Here we analyze the nature of these changes in expanded records from the Cambridge‐Dorchester and Mattawoman Creek‐Billingsley Road cores in Maryland. These cores comprise...
León y León, Isabel A.; Bralower, Timothy J.; Self-Trail, Jean M. 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...
Bolton, Clara T.; Bailey, Ian; Friedrich, Oliver; Tachikawa, Kazuyo; de Garidel‐Thoron, Thibault; Vidal, Laurence; Sonzogni, Corinne; Marino, Gianluca; Rohling, Eelco J.; Robinson, Marci M.; Ermini, Magali; Koch, Mirjam; Cooper, Matthew J.; Wilson, Paul A.
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...
DeWitt, Jessica D.; Chirico, Peter G.; Bergstresser, Sarah E.; Clark, Inga E. 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...
Edwards, Lucy E.; Weems, Robert E.; Carter, Mark W.; Spears, David; Powars, David S.