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Deep Arctic Ocean warming during the last glacial cycle Deep Arctic Ocean warming during the last glacial cycle

In the Arctic Ocean, the cold and relatively fresh water beneath the sea ice is separated from the underlying warmer and saltier Atlantic Layer by a halocline. Ongoing sea ice loss and warming in the Arctic Ocean have demonstrated the instability of the halocline, with implications for further sea ice loss. The stability of the halocline through past climate variations is unclear. Here...
Authors
T. M. Cronin, G. S. Dwyer, J. Farmer, H.A. Bauch, R.F. Spielhagen, M. Jakobsson, J. Nilsson, W. M. Briggs, A. Stepanova

Sequential development of platform to off-platform facies of the great American carbonate bank in the central Appalachians Sequential development of platform to off-platform facies of the great American carbonate bank in the central Appalachians

In the central Appalachians, carbonate deposition of the great American carbonate bank began during the Early Cambrian with the creation of initial ramp facies of the Vintage Formation and lower members of the Tomstown Formation. Vertical stacking of bioturbated subtidal ramp deposits (Bolivar Heights Member) and dolomitized microbial boundtsone (Fort Duncan Member) preceded the...
Authors
David K. Brezinski, John F. Taylor, John E. Repetski

Fragilariopsis diatom evolution in Pliocene and Pleistocene Antarctic shelf sediments 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...
Authors
Charlotte Sjunneskog, Christina Riesselman, Diane Winter, Reed Scherer

Spatial analysis of geologic and hydrologic features relating to sinkhole occurrence in Jefferson County, West Virginia Spatial analysis of geologic and hydrologic features relating to sinkhole occurrence in Jefferson County, West Virginia

In this study the influence of geologic features related to sinkhole susceptibility was analyzed and the results were mapped for the region of Jefferson County, West Virginia. A model of sinkhole density was constructed using Geographically Weighted Regression (GWR) that estimated the relations among discrete geologic or hydrologic features and sinkhole density at each sinkhole location...
Authors
Daniel H. Doctor, Katarina Z. Doctor

Neoproterozoic tectonic evolution of the Jebel Saghro and Bou Azzer - El Graara inliers, eastern and central Anti-Atlas, Morocco Neoproterozoic tectonic evolution of the Jebel Saghro and Bou Azzer - El Graara inliers, eastern and central Anti-Atlas, Morocco

New mapping, geochemistry, and 17 U–Pb SHRIMP zircon ages from rocks of the Sirwa, Bou Azzer–El Graara, and Jebel Saghro inliers constrain the Neoproterozoic evolution of the eastern Anti-Atlas during Pan-African orogenesis. In the Sirwa inlier, Tonian quartzite from the pre Pan-African passive margin deposits of the Mimount Formation contains detrital zircon derived entirely from the...
Authors
Gregory J. Walsh, John N. Aleinikoff, Richard W. Harrison, William C. Burton, James E. Quick, Foudad Benziane, Abdelaziz Yazidi, Abderrahim Saadane

Biostratigraphy and chronostratigraphy of the Cambrian-Ordovician great American carbonate bank Biostratigraphy and chronostratigraphy of the Cambrian-Ordovician great American carbonate bank

The carbonate strata of the great American carbonate bank (GACB) have been subdivided and correlated with ever-increasing precision and accuracy during the past half century through use of the dominant organisms that evolved on the Laurentian platform through the Cambrian and the Ordovician. Trilobites and conodonts remain the primary groups used for this purpose, although brachiopods...
Authors
John F. Taylor, John E. Repetski, James D. Loch, Stephen A. Leslie

The role of backbarrier infilling in the formation of barrier island systems 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...
Authors
Christopher J. Hein, Duncan M. FitzGerald, Emily A. Carruthers, Byron D. Stone, Allen M. Gontz

Was pre–twentieth century sea level stable? 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...
Authors
Thomas M. Cronin

Neither a year nor an annus can be a derived unit in the SI 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...
Authors
Lucy E. Edwards
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