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Derivation of habitat-specific dissolved oxygen criteria for Chesapeake Bay and its tidal tributaries

The Chesapeake 2000 Agreement committed its state and federal signatories to “define the water quality conditions necessary to protect aquatic living resources” in the Chesapeake Bay (USA) and its tidal tributaries. Hypoxia is one of the key water quality issues addressed as a result of the above Agreement. This paper summarizes the protection goals and specific criteria intended to achieve those
Authors
Richard A. Batiuk, Denise L. Breitburg, Robert J. Diaz, Thomas M. Cronin, David H. Secor, Glen Thursby

Surface temperatures of the Mid-Pliocene North Atlantic Ocean: Implications for future climate

The Mid-Pliocene is the most recent interval in the Earth's history to have experienced warming of the magnitude predicted for the second half of the twenty-first century and is, therefore, a possible analogue for future climate conditions. With continents basically in their current positions and atmospheric CO2 similar to early twenty-first century values, the cause of Mid-Pliocene warmth remains
Authors
Harry J. Dowsett, Mark A. Chandler, Marci M. Robinson

Bedrock geology of the Montpelier area, central Vermont

No abstract available.
Authors
Gregory J. Walsh, Jonathan Kim, Marjorie H. Gale

Stratigraphy and conodont biostratigraphy of the uppermost Carboniferous and Lower Permian from the North American Midcontinent

Part A The uppermost Wabaunsee, Admire, Council Grove, and lower Chase Groups of Kansas, Oklahoma, and Nebraska are placed into three third-order depositional sequences: a Gzhelian late-highstand sequence set, a Council Grove transgressive and highstand sequence set, and a Chase transgressive sequence set. Sequences are defined by bounding maximum-exposure surfaces and are placed within the zone o
Authors
Darwin R. Boardman, Bruce R. Wardlaw, Merlynd K. Nestell

Postimpact deposition in the Chesapeake Bay impact structure: Variations in eustasy, compaction, sediment supply, and passive-aggressive tectonism

The Eyreville and Exmore, Virginia, core holes were drilled in the inner basin and annular trough, respectively, of the Chesapeake Bay impact structure, and they allow us to evaluate sequence deposition in an impact crater. We provide new high-resolution geochronologic (<1 Ma) and sequence-stratigraphic interpretations of the Exmore core, identify 12 definite (and four possible) postimpact deposit
Authors
A.A. Kulpecz, K.G. Miller, J.V. Browning, Lucy E. Edwards, David S. Powars, P.P. McLaughlin, A.D. Harris, M.D. Feigenson

Arctic climate change and its impacts on the ecology of the North Atlantic

Arctic climate change from the Paleocene epoch to the present is reconstructed with the objective of assessing its recent and future impacts on the ecology of the North Atlantic. A recurring theme in Earth's paleoclimate record is the importance of the Arctic atmosphere, ocean, and cryosphere in regulating global climate on a variety of spatial and temporal scales. A second recurring theme in this
Authors
Charles H. Greene, Andrew J. Pershing, Thomas M. Cronin, Nicole Ceci

Red-Rimmed Melania (Melanoides tuberculatus) - A snail in Biscayne National Park, Florida - Harmful invader or just a nuisance?

Potentially harmful to humans and other animals, the red-rimmed melania snail (Melanoides tuberculatus; family Thiaridae) was discovered in Biscayne National Park, Florida, in 2003 by U.S. Geological Survey (USGS) researchers. The discovery raised concerns for park managers because this aquatic non-native snail is present in significant numbers in areas frequently used by park visitors and poses a
Authors
G. Lynn Wingard, James B. Murray, W. Bane Schill, Emily C. Phillips

Mid-Cenozoic tectonic and paleoenvironmental setting of the central Arctic Ocean

Drilling results from the Integrated Ocean Drilling Program's Arctic Coring Expedition (ACEX) to the Lomonosov Ridge (LR) document a 26 million year hiatus that separates freshwater-influenced biosilica-rich deposits of the middle Eocene from fossil-poor glaciomarine silty clays of the early Miocene. Detailed micropaleontological and sedimentological data from sediments surrounding this mid-Cenozo
Authors
M. O'Regan, K. Moran, J. Backman, M. Jakobsson, F. Sangiorgi, Henk Brinkhuis, Rob Pockalny, Alasdair Skelton, Catherine E. Stickley, N. Koc, Hans-Juergen Brumsack, Debra A. Willard

Reevaluation of mid-Pliocene North Atlantic sea surface temperatures

Multiproxy temperature estimation requires careful attention to biological, chemical, physical, temporal, and calibration differences of each proxy and paleothermometry method. We evaluated mid-Pliocene sea surface temperature (SST) estimates from multiple proxies at Deep Sea Drilling Project Holes 552A, 609B, 607, and 606, transecting the North Atlantic Drift. SST estimates derived from faunal as
Authors
Marci M. Robinson, Harry J. Dowsett, Gary S. Dwyer, Kira T. Lawrence

Hydrologic connections and dynamics of water movement in the classical Karst (Kras) aquifer: Evidence from frequent chemical and stable isotope sampling

A review of past researchon the hydrogeology of the Classical Karst (Kras) region and new information obtained from a two-year study using environmental tracers are presented in this paper. The main problems addressed are 1) the sources of water to the Kras aquifer resurgence zone—including the famous Ti­mavo springs—under changing flow regimes; 2) a quantifica­tion of the storage volumes of the k
Authors
Daniel H. Doctor

A 26 million year gap in the central Arctic record at the greenhouse-icehouse transition: Looking for clues

The Cenozoic record of the Lomonosov Ridge (central Arctic Ocean) recovered during Integrated Ocean Drilling Program (IODP) Expedition 302 revealed an unexpected 26 Ma hiatus, separating middle Eocene (∼44.4 Ma) from lower Miocene sediments (∼18.2 Ma). To elucidate the nature of this unconformity, we performed a multiproxy palynological (dinoflagellate cysts, pollen, and spores), micropaleontologi
Authors
Francesca Sangiorgi, Hans-Juergen Brumsack, Debra A. Willard, Stefan Schouten, Catherine E. Stickley, Matthew O'Regan, Gert-Jan Reichart, Jaap S. Sinninghe Damste, Henk Brinkhuis

Impact effects and regional tectonic insights: Backstripping the Chesapeake Bay impact structure

The Chesapeake Bay impact structure is a ca. 35.4 Ma crater located on the eastern seaboard of North America. Deposition returned to normal shortly after impact, resulting in a unique record of both impact-related and subsequent passive margin sedimentation. We use backstripping to show that the impact strongly affected sedimentation for 7 m.y. through impact-derived crustal-scale tectonics, domin
Authors
T. Hayden, M. Kominz, David S. Powars, Lucy E. Edwards, K.G. Miller, J.V. Browning, A.A. Kulpecz