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

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

Reevaluation of mid-Pliocene North Atlantic sea surface temperatures 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...
Authors
Marci M. Robinson, Harry J. Dowsett, Gary S. Dwyer, Kira T. Lawrence

Hydrogeology and Simulated Ground-Water Flow in the Salt Pond Region of Southern Rhode Island Hydrogeology and Simulated Ground-Water Flow in the Salt Pond Region of Southern Rhode Island

The Salt Pond region of southern Rhode Island extends from Westerly to Narragansett Bay and forms the natural boundary between the Atlantic Ocean and the shallow, highly permeable freshwater aquifer of the South Coastal Basin. Large inputs of fresh ground water coupled with the low flushing rates to the open ocean make the salt ponds particularly susceptible to eutrophication and...
Authors
John P. Masterson, Jason R. Sorenson, Janet Radway Stone, S. Bradley Moran, Andrea Hougham

Synthesis of age data and chronology for Florida Bay and Biscayne Bay cores collected for ecosystem history of South Florida’s estuaries project Synthesis of age data and chronology for Florida Bay and Biscayne Bay cores collected for ecosystem history of South Florida’s estuaries project

210Pb, 14C, and pollen biostratigraphic data have been compiled and synthesized to develop age models for cores collected from Florida Bay and Biscayne Bay. These cores are being used to interpret the ecosystem history of south Florida’s estuaries by examining the physical, chemical, and biological record preserved within the cores. The beginning of the 20th century, which marks an...
Authors
G. Lynn Wingard, J.W. Hudley, C. W. Holmes, Debra A. Willard, M. Marot

Integrated multi‐scale characterization of ground‐water flow and chemical transport in fractured crystalline rock at the Mirror Lake Site, New Hampshire Integrated multi‐scale characterization of ground‐water flow and chemical transport in fractured crystalline rock at the Mirror Lake Site, New Hampshire

This chapter contains sections titled: Introduction Mirror Lake Site Fractures and Geologic Mapping Hydraulic Properties of Fractured Rock From Meters to Kilometers Chemical Migration in Fractured Rock Fracture Controls on Ground‐Water Flow and Chemical Transport at the Mirror Lake Site Summary
Authors
Allen M. Shapiro, Paul A. Hsieh, William C. Burton, Gregory J. Walsh

Origin and emplacement of impactites in the Chesapeake Bay impact structure, Virginia, USA Origin and emplacement of impactites in the Chesapeake Bay impact structure, Virginia, USA

The late Eocene Chesapeake Bay impact structure, located on the Atlantic margin of Virginia, may be Earth's best-preserved large impact structure formed in a shallow marine, siliciclastic, continental-shelf environment. It has the form of an inverted sombrero in which a central crater ∼40 km in diameter is surrounded by a shallower brim, the annular trough, that extends the diameter to...
Authors
J. Wright Horton,, Gregory Gohn, David S. Powars, Lucy E. Edwards

A new species of Pentadinium from Eastern Anatolia, Turkey, Pentadinium galileoi A new species of Pentadinium from Eastern Anatolia, Turkey, Pentadinium galileoi

The new gonyaulacoid dinoflagellate Pentadinium galileoi Sancay et al., sp. nov. from the Oligocene-Lower Miocene sediments of Eastern Anatolia has been identified. It is spherical, chordate with prominant discoidal cingulum and distally furcate apical, sulcal, and antapical processes. It has a type P(3???) archeopyle, and periarcheopyle is larger than endoarcheopyle. Tabulation is...
Authors
R.H. Sancay, Z. Bati, Lucy E. Edwards, K.I. Ertug

Characterization of microtopography and its influence on vegetation patterns in created wetlands Characterization of microtopography and its influence on vegetation patterns in created wetlands

Created wetlands are increasingly used to mitigate wetland loss. Thus, identifying wetland creation methods that enhance ecosystem development might increase the likelihood of mitigation success. Noting that the microtopographic variation found in natural wetland settings may not commonly be found in created wetlands, this study explores relationships between induced microtopography...
Authors
K. Moser, C. Ahn, Gregory E. Noe

Post-middle Miocene origin of modern landforms in the eastern Piedmont of Virginia Post-middle Miocene origin of modern landforms in the eastern Piedmont of Virginia

Diverse late middle Miocene dinoflagellate floras, obtained from two sites along the western edge of the Atlantic Coastal Plain in central Virginia, indicate that the eastern Virginia Piedmont was covered by marine waters about 12-13 Ma. This transgression extended farther westward across the Virginia Piedmont than any other transgression that has been documented. Extensive fluvial...
Authors
Robert E. Weems, Lucy E. Edwards

Cytherellid species (Ostracoda) and their significance to the Late Quaternary events in the Santos Basin, Brazil Cytherellid species (Ostracoda) and their significance to the Late Quaternary events in the Santos Basin, Brazil

Four autochthonous cytherellid species (Cytherella serratula (BRADY, 1880), C. hermargentina WHATLEY et al. 1998, C. pleistocenica sp. nov. and C. santosensis sp. nov.) have been identified from two offshore cores (44 samples) within the Santos Basin. The distribution of these ostracodes is controlled by local hydrological conditions such as the temperature and, possibly, the oxygen...
Authors
C.T. Bergue, J.C. Coimbra, T. M. Cronin
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