Publications
Filter Total Items: 833
Quaternary displacement rates on the Meeman‐Shelby fault and Joiner ridge horst, eastern Arkansas: Results from coring Mississippi River alluvium
This research used coring and optically stimulated luminescence (OSL) dating of displaced, deeply buried Quaternary alluvium to determine vertical displacement rates for the Meeman‐Shelby fault and the Joiner ridge horst, two structures in northeastern Arkansas that have no modern seismicity associated with them. We drilled continuous cores of the entire alluvial section in the hanging wall of eac
Authors
Alex Ward, Ronald C. Counts, Roy Van Arsdale, Daniel Larsen, Shannon A. Mahan
Confirmation of the southwest continuation of the Cat Square terrane, southern Appalachian Inner Piedmont, with implications for middle Paleozoic collisional orogenesis
Detailed geologic mapping, U-Pb zircon geochronology and whole-rock geochemical analyses were conducted to test the hypothesis that the southwestern extent of the Cat Square terrane continues from the northern Inner Piedmont (western Carolinas) into central Georgia. Geologic mapping revealed the Jackson Lake fault, a ∼15 m-thick, steeply dipping sillimanite-grade fault zone that truncates litholog
Authors
Matthew T. Huebner, Robert D. Hatcher, Arthur J. Merschat
Biological response to climate change in the Arctic Ocean: The view from the past
The Arctic Ocean is undergoing rapid climatic changes including higher ocean temperatures, reduced sea ice, glacier and Greenland Ice Sheet melting, greater marine productivity, and altered carbon cycling. Until recently, the relationship between climate and Arctic biological systems was poorly known, but this has changed substantially as advances in paleoclimatology, micropaleontology, vertebrate
Authors
Thomas M. Cronin, Matthew A. Cronin
Emulation of long-term changes in global climate: application to the late Pliocene and future
Multi-millennial transient simulations of climate changes have a range of important applications, such as for investigating key geologic events and transitions for which high-resolution palaeoenvironmental proxy data are available, or for projecting the long-term impacts of future climate evolution on the performance of geological repositories for the disposal of radioactive wastes. However, due t
Authors
Natalie S. Lord, Michel Crucifix, Daniel J. Lunt, Mike C. Thorne, Nabila Bounceur, Harry J. Dowsett, Charlotte L. O'Brien, A. Ridgwell
Geologic map of the Washington West 30’ × 60’ quadrangle, Maryland, Virginia, and Washington D.C.
The Washington West 30’ × 60’ quadrangle covers an area of approximately 4,884 square kilometers (1,343 square miles) in and west of the Washington, D.C., metropolitan area. The eastern part of the area is highly urbanized, and more rural areas to the west are rapidly being developed. The area lies entirely within the Chesapeake Bay drainage basin and mostly within the Potomac River watershed. It
Authors
Peter T. Lyttle, John N. Aleinikoff, William C. Burton, E. Allen Crider, Avery A. Drake, Albert J. Froelich, J. Wright Horton, Gregorios Kasselas, Robert B. Mixon, Lucy McCartan, Arthur E. Nelson, Wayne L. Newell, Louis Pavlides, David S. Powars, C. Scott Southworth, Robert E. Weems
Geology and biostratigraphy of the Potomac River cliffs at Stratford Hall, Westmoreland County, Virginia
The cliffs along the Potomac River at Stratford Hall display extensive exposures of Miocene marine strata that belong successively to the Calvert, Choptank, St. Marys, and Eastover Formations. Within the lower part of this sequence, in the Calvert and Choptank Formations, there is well-developed cyclic stratigraphy. Above the Miocene units lies the marginal marine to deltaic Pleistocene Bacons Cas
Authors
Robert E. Weems, Lucy E. Edwards, Bryan D. Landacre
Post-rift magmatic evolution of the eastern North American “passive-aggressive” margin
Understanding the evolution of passive margins requires knowledge of temporal and chemical constraints on magmatism following the transition from supercontinent to rifting, to post-rifting evolution. The Eastern North American Margin (ENAM) is an ideal study location as several magmatic pulses occurred in the 200 My following rifting. In particular, the Virginia-West Virginia region of the ENAM ha
Authors
Sarah E. Mazza, Esteban Gazel, Elizabeth A. Johnson, Michael Bizmis, Ryan J. McAleer, C. Berk Biryol
Geology of the Petersburg batholith, eastern Piedmont, Virginia
The 295-300 Ma Petersburg batholith in east-central Virginia forms one of the largest and northernmost of the Alleghanian plutonic complexes in the southern Appalachian Piedmont. The batholith is primarily composed of granite including massive and foliated (both magmatic and solid-state fabrics) varieties. The plutonic complex intruded medium-grade metamorphosed volcanic/plutonic rocks of the Roan
Authors
Brent E. Owens, Mark W. Carter, Christopher M. Bailey
Geology along the Blue Ridge Parkway in Virginia
Detailed geologic mapping and new SHRIMP (sensitive high-resolution ion microprobe) U-Pb zircon, Ar/Ar, Lu-Hf, 14C, luminescence (optically stimulated), thermochronology (fission-track), and palynology reveal the complex Mesoproterozoic to Quaternary geology along the ~350 km length of the Blue Ridge Parkway in Virginia. Traversing the boundary of the central and southern Appalachians, rocks along
Authors
Mark W. Carter, C. Scott Southworth, Richard P. Tollo, Arthur J. Merschat, Sara Wagner, Ava Lazor, John N. Aleinikoff
An Arctic and Subarctic ostracode database: Biogeographic and paleoceanographic applications
A new Arctic Ostracode Database-2015 (AOD-2015) provides census data for 96 species of benthic marine Ostracoda from 1340 modern surface sediments from the Arctic Ocean and subarctic seas. Ostracoda is a meiofaunal, Crustacea group that secretes a bivalved calcareous (CaCO3) shell commonly preserved in sediments. Arctic and subarctic ostracode species have ecological limits controlled by temperatu
Authors
Laura Gemery, Thomas M. Cronin, William M. Briggs, Elisabeth M. Brouwers, Eugene I. Schornikov, Anna Stepanova, Adrian M. Wood, Moriaki Yasuhara
A simple rubric for Stratigraphic Fidelity (β) of paleoenvironmental time series
The Pliocene, specifically the late Pliocene, has been a focus of paleoclimate research formore than 25 years. Synoptic regional
and global reconstructions along with high-resolution time-series have produced nuanced conceptual models of paleoenvironmental
conditions and enhanced our understanding of climate variability and climate sensitivity from the Late Pliocene, the most
recent interval of gl
Authors
Harry J. Dowsett, Marci M. Robinson, Kevin M. Foley