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Publications

Filter Total Items: 823

Paleozoic and Mesozoic tectonic events west of the Waterbury Dome: Results of new mapping in the western Connecticut Highlands

This field trip highlights the results of recent U.S. Geological Survey (USGS) bedrock geologic mapping in four 7.5 min quadrangles in the western Connecticut highlands near Southbury, Connecticut, USA. The rocks are broadly within what Rodgers (1985) called the Hartland and Gneiss Dome belts of the Connecticut Valley Synclinorium (Rodgers, 1985; Fig. 1), the latter of which is now known as the Co
Authors
William C. Burton, William J. Devlin

Shallow marine ecosystem collapse and recovery during the Paleocene-Eocene Thermal Maximum

The Paleocene-Eocene Thermal Maximum (PETM), the most well-studied transient hyperthermal event in Earth history, is characterized by prominent and dynamic changes in global marine ecosystems. Understanding such biotic responses provides valuable insights into future scenarios in the face of anthropogenic warming. However, evidence of the PETM biotic responses is largely biased towards deep-sea re
Authors
Skye Y Tian, Moriaki Yasuhara, Huai-Hsuan M Huang, Fabien L. Condamine, Marci M. Robinson

Microfossils from Calvert Cliffs give us clues to the future warmer climate

No abstract available.
Authors
Seth R Sutton, Marci M. Robinson, Stephen J. Culver, David J. Mallinson, Martin A Buzas, Harry J. Dowsett

Watershed and estuarine controls both influence plant community and tree growth changes in tidal freshwater forested wetlands along two U.S. mid-Atlantic rivers

The tidal freshwater zone near the estuarine head-of-tide is potentially sensitive to both sea-level rise and associated salinity increases as well as changing watershed inputs of freshwater and nutrients. We evaluated the vegetation response of tidal freshwater forested wetlands (TFFW) to changes in nontidal river versus estuarine controls along the longitudinal gradient of the Mattaponi and Pamu
Authors
Gregory B. Noe, Norman A Bourg, Ken Krauss, Jamie A. Duberstein, Cliff R. Hupp

The Holocene dynamics of Ryder Glacier and ice tongue in north Greenland

The northern sector of the Greenland Ice Sheet is considered to be particularly susceptible to ice mass loss arising from increased glacier discharge in the coming decades. However, the past extent and dynamics of outlet glaciers in this region, and hence their vulnerability to climate change, are poorly documented. In the summer of 2019, the Swedish icebreaker Oden entered the previously uncharte
Authors
Matt O'Regan, Thomas M. Cronin, Brendan Reilly, Aage K. Olsen Alstrup, Laura Gemery, Anna Golub, Larry A. Mayer, Mathieu Morlighem, Matthias Moros, Ole L. Munk, Johan Nilsson, Christof Pearce, Henrieka Detlef, Christian Stranne, Flor Vermassen, Gabriel West, Martin Jakobsson

Ten years on from the quake that shook the nation’s capital

No abstract available.
Authors
Thomas L. Pratt, Martin C. Chapman, Anjana K. Shah, J. Wright Horton,, Oliver S. Boyd

Mg/Ca ratios in ostracode genera Sarsicytheridea and Paracyprideis: A potential paleotemperature proxy for Arctic and subarctic continental shelf and slope waters

We evaluate the potential utility of Mg/Ca ratios in the sublittoral ostracode genera Sarsicytheridea and Paracyprideis as a paleotemperature proxy for continental shelf and upper slope waters of the Arctic Ocean and adjacent seas. Using sediment core-top and surface sediment samples, the shells of three species, S. bradii, S. punctillata, and P. pseudopunctillata, were analyzed from Arctic Ocean
Authors
Thomas M. Cronin, Gary S. Dwyer, Katherine Keller, Laura Gemery, Jesse R. Farmer

Arctic Ocean stratification set by sea level and freshwater inputs since the last ice age

Salinity-driven density stratification of the upper Arctic Ocean isolates sea-ice cover and cold, nutrient-poor surface waters from underlying warmer, nutrient-rich waters. Recently, stratification has strengthened in the western Arctic but has weakened in the eastern Arctic; it is unknown if these trends will continue. Here we present foraminifera-bound nitrogen isotopes from Arctic Ocean sedimen
Authors
Jesse R. Farmer, Daniel Sigman, Julie Granger, Ona M. Underwood, Francois Frapiat, Thomas M. Cronin, Alfredo Martínez-García, Gerald H. Haug

Miocene neritic benthic foraminiferal community dynamics, Calvert Cliffs, Maryland, USA: Species pool, patterns and processes

The presence/absence and abundance of benthic foraminifera in successive discrete beds (Shattuck “zones”) of the Miocene Calvert and Choptank formations, exposed at the Calvert Cliffs, Maryland, USA, allows for investigation of community dynamics over space and time. The stratigraphic distribution of benthic foraminifera is documented and interpreted in the context of sea-level change, sequence st
Authors
Stephen J. Culver, Seth R Sutton, David J. Mallinson, Martin A Buzas, Marci M. Robinson, Harry J. Dowsett

The Chesapeake Bay program modeling system: Overview and recommendations for future development

The Chesapeake Bay is the largest, most productive, and most biologically diverse estuary in the continental United States providing crucial habitat and natural resources for culturally and economically important species. Pressures from human population growth and associated development and agricultural intensification have led to excessive nutrient and sediment inputs entering the Bay, negatively
Authors
Raleigh Hood, Gary W. Shenk, Rachel L Dixon, Sean M. C. Smith, William P. Ball, Jesse Bash, R. Batiuk, Kathy Boomer, Damian C Brady, Carl Cerco, Peter Claggett, Kim de Mutsert, Zachary M. Easton, Andrew J Elmore, Marjorie A. M. Friedrichs, Lora A. Harris, Thomas F. Ihde, Iara Lacher, Li Li, Lewis C. Linker, Andrew Miller, Julia Moriarty, Gregory B. Noe, George Onyullo, Kenneth A Rose, Katherine Skalak, Richard Tian, Tamie L Veith, Lisa A. Wainger, Donald E. Weller, Yinglong J. Zhang

Borehole sampling of surficial sediments in Northern Virginia and Southern Maryland

From 2014 to 2017, the U.S. Geological Survey’s Florence Bascom Geoscience Center (FBGC) entered into an inter-agency agreement with the Federal Highway Administration’s Turner-Fairbank Highway Research Center (TFHRC) to assist in field site selection and auger drilling fieldwork. The TFHRC was developing a device to measure the erosional properties of clay-rich sediments to be used for in situ te
Authors
Peter G. Chirico, Jessica D. DeWitt, Sarah E. Bergstresser

Afghanistan artisanal and small-scale mining sector

For millennia, extractive activity in Afghanistan (officially the Islamic Republic of Afghanistan, or IRA) has been entirely artisanal or small-scale in scope. Various international governments, organizations, and companies have supported the growth of the sector, and the Government of the Islamic Republic of Afghanistan (GoIRA) views its mineral wealth as vital to the country’s stability and pros
Authors
Jessica D. DeWitt, Sindhuja Sunder, Kathleen M Boston