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Publications

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Calibrated relative sea levels constrain isostatic adjustment and ice history in northwest Greenland

Relative Sea Levels (RSLs) derived primarily from marine bivalves near Petermann Glacier, NW Greenland, constrain past regional ice-mass changes through glacial isostatic adjustment (GIA) modeling. Oxygen isotopes measured on bivalves corrected for shell-depth habitat and document changing meltwater input. Rapid RSL fall of up to 62 m/kyr indicates ice loss at or prior to ∼9 ka. Transition to an R
Authors
Anna Glueder, Alan Mix, Glenn A. Milne, Brendan Reilly, Jorie Clark, Martin Jakobsson, Larry Mayer, Stewart Fallon, John R. Southon, June Padman, Andrew Ross, Thomas M. Cronin, Jennifer McKay

Don't judge an orogen by its cover: Kinematics of the Appalachian décollement from seismic anisotropy

As North America collided with Africa to form Pangea during the Alleghanian orogeny, crystalline and sedimentary rocks in the southeastern United States were thrust forelandward along the Appalachian décollement. We examined Ps receiver functions to better constrain the kinematics of this prominent subsurface structure. From Southeastern Suture of the Appalachian Margin Experiment (SESAME) and oth
Authors
Michael G. Frothingham, Vera Schulte-Pelkum, Kevin H. Mahan, Arthur J. Merschat, Makayla Mather, Zulliet Cabrera Gomez

Recent climate change has driven divergent hydrological shifts in high-latitude peatlands

High-latitude peatlands are changing rapidly in response to climate change, including permafrost thaw. Here, we reconstruct hydrological conditions since the seventeenth century using testate amoeba data from 103 high-latitude peat archives. We show that 54% of the peatlands have been drying and 32% have been wetting over this period, illustrating the complex ecohydrological dynamics of high latit
Authors
Hui Zhang, Minna Valiranta, Graeme T. Swindles, Marco Aquino-Lopez, Donal Mullan, Ning Tan, Matthew Amesbury, Kirill Babeshko, Kunshan Bao, Anatoly Bobrov, Viktor Chernyshov, Marissa A. Davies, Andrei-Cosmin Diaconu, Angelica Feurdean, Sarah A. Finkelstein, Michelle Garneau, Zhengtang Guo, Miriam C. Jones, Martin Kay, Eric S. Klein, Maruisz Lamentowicz, Gabriel Magnan, Katarzyna Marcisz, Natalia Mazei, Yuri Mazei, Richard Payne, Nicolas Pelletier, Sanna Piilo, Steve Pratte, Thomas P. Roland, Damir Saldaev, William Shotyk, Thomas G. Sim, Thomas J Sloan, Michał Słowiński, Julie Talbot, Liam Taylor, Andrey N. Tsyganov, Sebastian Wetterich, Wei Xing, Yan Zhao

Using paleoecological data to inform decision making: A deep-time perspective

Latest climate models project conditions for the end of this century that are generally outside of the human experience. These future conditions affect the resilience and sustainability of ecosystems, alter biogeographic zones, and impact biodiversity. Deep-time records of paleoclimate provide insight into the climate system over millions of years and provide examples of conditions very different
Authors
Harry J. Dowsett, Peter Jacobs, Kim de Mutsert

Germanium redistribution during weathering of Zn mine wastes: Implications for environmental mobility and recovery of a critical mineral

Germanium (Ge) is a metal used in emerging energy technologies, communications, and defense, and has been deemed critical by the United States due to its essential applications and scarce supply. Germanium is recovered as a byproduct of zinc (Zn) sulfides, and mining and processing of these materials lead to waste that could act both as a source of extractable Ge and a source for exposure to human
Authors
Sarah Jane White, Nadine M. Piatak, Ryan J. McAleer, Sarah M. Hayes, Robert R. Seal, Laurel A. Schaider, James P. Shine

Using mollusks as indicators of restoration in nearshore zones of south Florida's estuaries

Current south Florida ecosystem restoration efforts are focused on restoring more natural freshwater flow through the wetlands and into the estuaries to reestablish natural salinity gradients, particularly in the nearshore zones. Indicator taxa are used to monitor and assess restoration progress and the current suite of biota used for the estuaries in south Florida (Biscayne Bay, Florida Bay, and
Authors
G. Lynn Wingard, Bethany Stackhouse, Andre Daniels

Potential for critical mineral deposits in Maine, USA

An analysis of the potential for deposits of critical minerals and elements in Maine presented here includes data and discussions for antimony, beryllium, cesium, chromium, cobalt, graphite, lithium, manganese, niobium, platinum group elements, rhenium, rare earth elements, tin, tantalum, tellurium, titanium, uranium, vanadium, tungsten, and zirconium. Deposits are divided into two groups based on
Authors
John F. Slack, F.M. Beck, D.C. Bradley, M. M. Felch, Robert G. Marvinney, A.T.H. Whittaker

Implementation plan of the National Cooperative Geologic Mapping Program strategy — Appalachian Piedmont and Blue Ridge Provinces

The National Cooperative Geologic Mapping Program is publishing a strategic plan titled “Renewing the National Cooperative Geologic Mapping Program as the Nation’s Authoritative Source for Modern Geologic Knowledge.” The plan provides a vision, mission, and goals for the program for the years 2020–30:Vision: create an integrated, three-dimensional, digital geologic map of the United States.Mission
Authors
Arthur J. Merschat, Mark W. Carter

Spectral mixture analysis for surveillance of harmful algal blooms (SMASH): A field-, laboratory-, and satellite-based approach to identifying cyanobacteria genera from remotely sensed data

Algal blooms around the world are increasing in frequency and severity, often with the possibility of adverse effects on human and ecosystem health. The health and economic impacts associated with harmful algal blooms, or HABs, provide compelling rationale for developing new methods for monitoring these events via remote sensing. Although concentrations of chlorophyll-a and key pigments like phyco
Authors
Carl J. Legleiter, Tyler Victor King, Kurt D. Carpenter, Natalie Celeste Hall, Adam Mumford, E. Terrence Slonecker, Jennifer L. Graham, Victoria G. Stengel, Nancy Simon, Barry H. Rosen

The Pliocene-to-present course of the Tennessee River

The Tennessee River, a primary drainage of the southern Appalachians and significant sediment source for the Gulf of Mexico, is generally considered to be the product of captures that rerouted the river from a more direct gulfward course. Sedimentary and genetic evidence indicates that a paleo-Tennessee flowed into the Mobile Basin through the late Miocene, although alternate models propose other
Authors
William Elijah Odom, Darryl E. Granger

Hydrologic controls on peat permafrost and carbon processes: New insights from past and future modeling

Soil carbon (C) in permafrost peatlands is vulnerable to decomposition with thaw under a warming climate. The amount and form of C loss likely depends on the site hydrology following permafrost thaw, but antecedent conditions during peat accumulation are also likely important. We test the role of differing hydrologic conditions on rates of peat accumulation, permafrost formation, and response to w
Authors
Claire C. Treat, Miriam C. Jones, Jay R. Alder, Steve Frolking

Streambank and floodplain geomorphic change and contribution to watershed material budgets

Stream geomorphic change is highly spatially variable but critical to landform evolution, human infrastructure, habitat, and watershed pollutant transport. However, measurements and process models of streambank erosion and floodplain deposition and resulting sediment fluxes are currently insufficient to predict these rates in all perennial streams over large regions. Here we measured long-term lat
Authors
Gregory B. Noe, Kristina G. Hopkins, Peter Claggett, Edward R. Schenk, Marina Metes, Labeeb Ahmed, Tom Doody, Cliff R. Hupp