Publications
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Digital geologic map data for the Ozark National Scenic Riverways and adjacent areas along the Current River and Jacks Fork, Missouri Digital geologic map data for the Ozark National Scenic Riverways and adjacent areas along the Current River and Jacks Fork, Missouri
The geology of the Ozark National Scenic Riverways (ONSR) in southern Missouri has been mapped at 1:24,000 scale. This endeavor was achieved through the combined efforts of U.S. Geological Survey and Missouri Geological Survey individual quadrangle mapping and additional fieldwork by the authors of this report. Geologic data covering the area of the ONSR and a 1-mile (1.6-kilometer)...
Authors
David J. Weary, Randall C. Orndorff, Richard W. Harrison, Robert E. Weems
Synthesis and revision of the lithostratigraphic groups and formations in the Upper Permian?–Lower Jurassic Newark Supergroup of eastern North America Synthesis and revision of the lithostratigraphic groups and formations in the Upper Permian?–Lower Jurassic Newark Supergroup of eastern North America
The Upper Permian? - Lower Jurassic Newark Supergroup of eastern North America has a strikingly uniform succession of lithologic units. This uniformity is seen regardless of whether these units are characterized on the basis of their lithostratigraphy, allostratigraphy, biostratigraphy, or chemostratigraphy. After deposition, these units were broken up tectonically and attacked...
Authors
Robert E. Weems, Lawrence H. Tanner, Spencer G. Lucas
Holocene climate changes in eastern Beringia (NW North America) – A systematic review of multi-proxy evidence Holocene climate changes in eastern Beringia (NW North America) – A systematic review of multi-proxy evidence
Reconstructing climates of the past relies on a variety of evidence from a large number of sites to capture the varied features of climate and the spatial heterogeneity of climate change. This review summarizes available information from diverse Holocene paleoenvironmental records across eastern Beringia (Alaska, westernmost Canada and adjacent seas), and it quantifies the primary trends...
Authors
Darrell S. Kaufman, Yarrow L. Axford, Andrew C.G. Henderson, Nicolas P. McKay, W. Wyatt Oswald, Casey Saenger, R. Scott Anderson, Hannah L. Bailey, Benjamin Clegg, Konrad Gajewski, Feng Sheng Hu, Miriam C. Jones, Charly Massa, Cody C. Routson, Al Werner, Matthew J. Wooller, Zicheng Yu
Centimeter-scale surface deformation caused by the 2011 Mineral, Virginia, earthquake sequence at the Carter farm site—Subsidiary structures with a quaternary history Centimeter-scale surface deformation caused by the 2011 Mineral, Virginia, earthquake sequence at the Carter farm site—Subsidiary structures with a quaternary history
Centimeter-scale ground-surface deformation was produced by the August 23, 2011, magnitude (M) 5.8 earthquake that occurred in Mineral, Virginia. Ground-surface deformation also resulted from the earthquake aftershock sequence. This deformation occurred along a linear northeast-trend near Pendleton, Virginia. It is approximately 10 kilometers (km) northeast of the M5.8 epicenter and near...
Authors
Richard W. Harrison, J. Stephen Schindler, Milan J. Pavich, J. Wright Horton, Mark W. Carter
Analysis of hydrologic and geochemical time-series data at James Cave, Virginia: Implications for epikarst influence on recharge in Appalachian karst aquifers Analysis of hydrologic and geochemical time-series data at James Cave, Virginia: Implications for epikarst influence on recharge in Appalachian karst aquifers
The epikarst, which consists of highly weathered rock in the upper vadose zone of exposed karst systems, plays a critical role in determining the hydrologic and geochemical characteristics of recharge to an underlying karst aquifer. This study utilized time series (2007–2014) of hydrologic and geochemical data of drip water collected within James Cave, Virginia, to examine the influence...
Authors
Sarah D. Eagle, William Orndorff, Benjamin F. Schwartz, Daniel H. Doctor, Jonathan D. Gerst, Madeline E. Schreiber
The PRISM4 (mid-Piacenzian) paleoenvironmental reconstruction The PRISM4 (mid-Piacenzian) paleoenvironmental reconstruction
The mid-Piacenzian is known as a period of relative warmth when compared to the present day. A comprehensive understanding of conditions during the Piacenzian serves as both a conceptual model and a source for boundary conditions as well as means of verification of global climate model experiments. In this paper we present the PRISM4 reconstruction, a paleoenvironmental reconstruction of...
Authors
Harry J. Dowsett, Aisling M. Dolan, David Rowley, Robert Moucha, Alessandro Forte, Jerry X. Mitrovica, Matthew Pound, Ulrich Salzmann, Marci M. Robinson, Mark Chandler, Kevin M. Foley, Alan M. Haywood
The intertropical convergence zone modulates intense hurricane strikes on the western North Atlantic margin The intertropical convergence zone modulates intense hurricane strikes on the western North Atlantic margin
Most Atlantic hurricanes form in the Main Development Region between 9°N to 20°N along the northern edge of the Intertropical Convergence Zone (ITCZ). Previous research has suggested that meridional shifts in the ITCZ position on geologic timescales can modulate hurricane activity, but continuous and long-term storm records are needed from multiple sites to assess this hypothesis. Here...
Authors
Peter J. van Hengstrum, Jeffrey P. Donnelly, Patricia L. Fall, Michael Toomey, Nancy A. Albury, Brian Kakuk
A new specimen of Agorophius pygmaeus (Agorophiidae, Odontoceti, Cetacea) from the Early Oligocene Ashley Formation of South Carolina, USA A new specimen of Agorophius pygmaeus (Agorophiidae, Odontoceti, Cetacea) from the Early Oligocene Ashley Formation of South Carolina, USA
The holotype partial skull of Agorophius pygmaeus (the monotypic form for both the genus Agorophius and the Family Agorophiidae) has been missing for approximately 140 years. Since the discovery of Agorophius pygmaeus, many additional taxa and specimens have been placed in the Family Agorophiidae, only to be reclassified and removed later. This has created confusion as to what is and...
Authors
Stephen J. Godfrey, Mark D. Uhen, Jason E. Osborne, Lucy E. Edwards
Geologic evolution of the lower Connecticut River valley: Influence of bedrock geology, glacial deposits, and sea level Geologic evolution of the lower Connecticut River valley: Influence of bedrock geology, glacial deposits, and sea level
This fieldtrip illustrates the character of the lower Connecticut River bedrock valley, in particular its depth, and the lithology and structure of bedrock units it crosses. It examines the character and distribution of the glaciodeltaic terraces that partially fill the valley and discusses the depth of postglacial incision into them.
Authors
Janet Radway Stone, Ralph S. Lewis
Climate change Climate change
Climate change (including climate variability) refers to regional or global changes in mean climate state or in patterns of climate variability over decades to millions of years often identified using statistical methods and sometimes referred to as changes in long-term weather conditions (IPCC, 2012). Climate is influenced by changes in continent-ocean configurations due to plate...
Authors
Thomas M. Cronin
Cenozoic sea level and the rise of modern rimmed atolls Cenozoic sea level and the rise of modern rimmed atolls
Sea-level records from atolls, potentially spanning the Cenozoic, have been largely overlooked, in part because the processes that control atoll form (reef accretion, carbonate dissolution, sediment transport, vertical motion) are complex and, for many islands, unconstrained on million-year timescales. Here we combine existing observations of atoll morphology and corelog stratigraphy...
Authors
Michael Toomey, Andrew Ashton, Maureen E. Raymo, J. Taylor Perron
Sensitivity of Pliocene Arctic climate to orbital forcing, atmospheric CO2 and sea ice albedo parameterisation Sensitivity of Pliocene Arctic climate to orbital forcing, atmospheric CO2 and sea ice albedo parameterisation
General circulation model (GCM) simulations of the mid-Pliocene Warm Period (mPWP, 3.264 to 3.025 Myr ago) do not reproduce the magnitude of Northern Hemisphere high latitude surface air and sea surface temperature (SAT and SST) warming that proxy data indicate. There is also large uncertainty regarding the state of sea ice cover in the mPWP. Evidence for both perennial and seasonal mPWP...
Authors
Fergus W. Howell, Alan M. Haywood, Harry J. Dowsett, Steven J. Pickering