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Publications

Filter Total Items: 825

Calcareous nannofossil assemblage changes across the Paleocene-Eocene thermal maximum: Evidence from a shelf setting

Biotic response of calcareous nannoplankton to abrupt warming across the Paleocene/Eocene boundary reflects a primary response to climatically induced parameters including increased continental runoff of freshwater, global acidification of seawater, high sedimentation rates, and calcareous nannoplankton assemblage turnover. We identify ecophenotypic nannofossil species adapted to low pH conditions
Authors
Jean M. Self-Trail, David S. Powars, David K. Watkins, Gregory A. Wandless

Ages of pre-rift basement and synrift rocks along the conjugate rift and transform margins of the Argintine Precordillera and Laurentia

New geochronologic data from basement rocks support the interpretation that the Argentine Precordillera (Cuyania) terrane was rifted from the Ouachita embayment of the Iapetan margin of Laurentia. New data from the Ozark dome show a range of ages in two groups at 1466 ± 3 to 1462 ± 1 Ma and 1323 ± 2 to 1317 ± 2 Ma, consistent with existing data for the Eastern Granite-Rhyolite province and Souther
Authors
William A. Thomas, Robert D. Tucker, Ricardo A. Astini, Rodger E. Denison

Fragilariopsis diatom evolution in Pliocene and Pleistocene Antarctic shelf sediments

The late Pliocene – early Pleistocene sediment record in the AND-1B core from the McMurdo Sound, Ross Sea, Antarctica, displays a rich diversity and high abundance of diatoms, including several new morphologies within the genus Fragilariopsis. These new morphologies exhibit similarities to the extinct late Miocene/early Pliocene species Fragilariopsis aurica Gersonde and Fragilariopsis praecurta G
Authors
Charlotte Sjunneskog, Christina Riesselman, Diane Winter, Reed Scherer

A transect across the basement massifs of the central Green Mountains, Vermont

No abstract available.
Authors
Gregory J. Walsh, Nicholas M. Ratcliffe, Michael J. Kunk

The role of backbarrier infilling in the formation of barrier island systems

Barrier islands develop through a variety of processes, including spit accretion, barrier elongation, and inlet filling. New geophysical and sedimentological data provide a means of documenting the presence of a paleoinlet within a barrier lithosome in the western Gulf of Maine, illuminating the process of backbarrier infilling and its effect on barrier and tidal inlet morphodynamics. The transpor
Authors
Christopher J. Hein, Duncan M. FitzGerald, Emily A. Carruthers, Byron D. Stone, Allen M. Gontz

Traverse of the major fault systems of the Taconian deformational front, the Vermont Valley and core of the Green Mountain massif, southern Vermont

No abstract available.
Authors
Nicholas M. Ratcliffe, Michael J. Kunk, William C. Burton, Gregory J. Walsh

Was pre–twentieth century sea level stable?

Sea level rise (SLR) ranks high on the list of climate change issues because the expected acceleration from the current rate (about 3.1 millimeters per year) poses threats to coastal regions. Tide gauge, salt marsh, and archaeological records, and modeling of glacioisostatic adjustment (GIA) have led to the widely accepted idea that late Holocene (the past ∼2000 years) sea level was stable prior t
Authors
Thomas M. Cronin

Neither a year nor an annus can be a derived unit in the SI

The year is not a unit of the SI. The only SI unit of measurement for time is the second. The word “annus” or “annum” does not appear anywhere in the current SI document. The word “year” is not in the table of “Non-SI units accepted for use with the International System of Units,” nor in the table of “Non-SI units whose values in SI units must be obtained experimentally,” nor even in the table
Authors
Lucy E. Edwards

The Holocene history of Nares Strait: Transition from glacial bay to Arctic-Atlantic throughflow

Retreat of glacier ice from Nares Strait and other straits in the Canadian Arctic Archipelago after the end of the last Ice Age initiated an important connection between the Arctic and the North Atlantic Oceans, allowing development of modern ocean circulation in Baffin Bay and the Labrador Sea. As low-salinity, nutrient-rich Arctic Water began to enter Baffin Bay, it contributed to the Baffin and
Authors
Anne E. Jennings, Christina Sheldon, Thomas M. Cronin, Pierre Francus, Joseph Stoner, John Andrews

Detailed sections from auger holes in the Elizabethtown 1:100,000-scale quadrangle, North Carolina

The Elizabethtown 1:100,000 quadrangle is in the west-central part of the Coastal Plain of southeastern North Carolina. The Coastal Plain, in this region, consists mostly of unlithified sediments that range in age from Late Cretaceous to Holocene. These sediments lie with profound unconformity on complexly deformed metamorphic and igneous rocks similar to rocks found immediately to the west in the
Authors
Robert E. Weems, William C. Lewis, Joseph H. Murray, David B. Queen, Jeffrey B. Grey, Benjamin D. DeJong

Surficial geologic map of the Elizabethtown 30' x 60' quadrangle, North Carolina

The Elizabethtown 30' x 60' quadrangle is located in southeastern North Carolina between Fayetteville and Wilmington. Most of the area is flat to gently rolling, although steep slopes occur locally along some of the larger streams. Total relief in the area is slightly over 210 feet (ft), with elevations ranging from slightly less than 10 ft above sea level along the Black River (east of Rowan in t
Authors
Robert E. Weems, William C. Lewis, E. Allen Crider