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Publications

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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 the mid-P
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

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 we present

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

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 what is not a
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

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 (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 tectonic process
Authors
Thomas M. Cronin

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 from Enewetak
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

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 Arctic se
Authors
Fergus W. Howell, Alan M. Haywood, Harry J. Dowsett, Steven J. Pickering

Quantification of a pretreatment procedure for organic-rich calcareous nannofossil samples

No abstract available.
Authors
Jamie L. Shamrock, Jean Self-Trail

Proposed Auxiliary Boundary Stratigraphic Section and Point (ASSP) for the base of the Ordovician System at Lawson Cove, Utah, USA

The Global boundary Stratotype Section and Point (GSSP) for the base of the Ordovician System is at the First Appearance Datum (FAD) of the conodont Iapetognathus fluctivagus at Green Point in Newfoundland, Canada. Strata there are typical graptolitic facies that were deposited near the base of the continental slope.We propose establishing an Auxiliary boundary Stratotype Section and Point (ASSP)
Authors
James F. Miller, Kevin R. Evans, Raymond L. Ethington, Rebecca Freeman, James D. Loch, John E. Repetski, Robert Ripperdan, John F. Taylor

A multiagency and multijurisdictional approach to mapping the glacial deposits of the Great Lakes region in three dimensions

The Great Lakes Geologic Mapping Coalition (GLGMC), consisting of state geological surveys from all eight Great Lakes states, the Ontario Geological Survey, and the U.S. Geological Survey, was conceived out of a societal need for unbiased and scientifically defensible geologic information on the shallow subsurface, particularly the delineation, interpretation, and viability of groundwater resource
Authors
Richard C. Berg, Steven E. Brown, Jason F. Thomason, Nancy R. Hasenmueller, Sally L. Letsinger, Kevin A. Kincare, John M. Esch, Alan E. Kehew, Harvey Thorleifson, Andrew Kozlowski, Brian C. Bird, Richard R. Pavey, Andy F. Bajc, Abigail K. Burt, Gary M. Fleeger, Eric C. Carson

The Pliocene Model Intercomparison Project (PlioMIP) Phase 2: Scientific objectives and experimental design

The Pliocene Model Intercomparison Project (PlioMIP) is a co-ordinated international climate modelling initiative to study and understand climate and environments of the Late Pliocene, as well as their potential relevance in the context of future climate change. PlioMIP examines the consistency of model predictions in simulating Pliocene climate and their ability to reproduce climate signals prese
Authors
Alan M. Haywood, Harry J. Dowsett, Aisling M. Dolan, David Rowley, Ayako Abe-Ouchi, Bette Otto-Bliesner, Mark A. Chandler, Stephen J. Hunter, Daniel J. Lunt, Matthew Pound, Ulrich Salzmann

The “Anthropocene” epoch: Scientific decision or political statement?

The proposal for the “Anthropocene” epoch as a formal unit of the geologic time scale has received extensive attention in scientific and public media. However, most articles on the Anthropocene misrepresent the nature of the units of the International Chronostratigraphic Chart, which is produced by the International Commission on Stratigraphy (ICS) and serves as the basis for the geologic time sca
Authors
Stanley C. Finney, Lucy E. Edwards