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Deformation-induced graphitization and muscovite recrystallization in a ductile fault zone

A suite of slate samples collected along a 2 km transect crossing the Lishan fault in central Taiwan were evaluated to assess the role of ductile deformation in natural graphitization at lower greenschist facies metamorphic conditions. The process of natural aromatization, or graphitization, of an organic precursor is well established as a thermally driven process; however, experimental studies ha
Martha (Rebecca) Stokes, Aaron M. Jubb, Ryan J. McAleer, David Bish, Robert Wintsch

Morphotypical and geochemical variations of planktic foraminiferal species in Siberian and Central Arctic Ocean core tops

In this work, we utilize a transect of core top, mid- to late Holocene, sediments from the Eastern Siberian Sea to the central Arctic Ocean, spanning gradients in upper-ocean water column properties, to examine regional planktic foraminiferal species abundances and geochemistry. We present species- and morphotype-specific foraminiferal assemblages at these sites and stable isotope analyses of neog
Maya Prabhakar, Kaustubh Thirumalai, Thomas M. Cronin, Laura Gemery, Elizabeth Thomas, Patrick Rafter

Saltwater intrusion and sea level rise threatens U.S. rural coastal landscapes and communities

The United States (U.S.) coastal plain is subject to rising sea levels, land subsidence, more severe coastal storms, and more intense droughts. These changes lead to inputs of marine salts into freshwater-dependent coastal systems, creating saltwater intrusion. The penetration of salinity into the coastal interior is exacerbated by groundwater extraction and the high density of agricultural canals
Kiera O'Donnell, Emily S. Bernhardt, Xi Yang, Ryan Emanuel, Marcelo Ardon, Manuel Lerdau, Alex Manda, Anna Braswell, Todd BenDor, Eric Edwards, Elizabeth Frankenberg, Ashley Helton, John Kominoski, Amy Lesen, Lindsay Naylor, Gregory B. Noe, Kate Tully, Elliott White, Justin Wright

Using local monitoring results to inform the Chesapeake Bay Program’s Watershed Model

The Chesapeake Bay Program’s Watershed Model (CBWM) has been used as an accounting tool for the Chesapeake Bay Total Maximum Daily Load (TMDL). However, some of the fundamental parameters that underpin the watershed model may not represent local watershed characteristics at all scales. Significant investments have been made by state and local governments, and other local stakeholders, who are int
Karl Berger, Katherine C. Filippino, Gary W. Shenk, Normand Goulet, Michael Lookenbill, Doug L. Moyer, Gregory B. Noe, Aaron J. Porter, James Shallenberger, Bryant Thomas, Guido Yactayo

Microfossils and biostratigraphy of the Upper Cretaceous Coon Creek Formation Lagerstätte, Mississippi Embayment, USA

The Upper Cretaceous Coon Creek Formation type-locality in McNairy County, Tennessee, is an exceptional marine invertebrate Lagerstätte that was deposited in a nearshore reentrant into the ancestral continent of Appalachia. Extensive taxonomic analysis of the macrofauna has been done for over 100 years. However, documentation of the microfossil component at the type-locality has largely been ignor
Jean Self-Trail, Kristina Frank Gardner, Jennifer M K O'Keefe, Patricia H. Mason, Mark Puckett, Michael A. Gibson, Maeve McCarty

Pliocene Model Intercomparison Project Phase 3 (PlioMIP3) – Science plan and experimental design

The Pliocene Model Intercomparison Project (PlioMIP) was initiated in 2008. Over two phases PlioMIP has helped co-ordinate the experimental design and publication strategy of the community, which has included an increasing number of climate models and modelling groups from around the world. It has engaged with palaeoenvironmental scientists to foster new data synthesis supporting the construction
Alan M Haywood, Julia C. Tindall, Lauren Burton, M.A. Chandler, Aisling M Dolan, Harry J. Dowsett, R. Feng, Tamara Fletcher, Kevin M. Foley, Daniel Hill, Stephen Hunter, B. Otto-Bliesner, D.J. Lunt, Marci M. Robinson, U. Salzmann

Insights into glendonite formation from the upper Oligocene Sagavanirktok Formation, North Slope, Alaska

The type locality for the upper Oligocene Nuwok Member of the Sagavanirktok Formation (Carter Creek, North Slope, Alaska, USA) contains abundant occurrence of glendonite, a pseudomorph after the calcium carbonate mineral ikaite, which typically forms in the shallow subsurface of cold marine sediments. The region during the time of Nuwok Member deposition was located at a high latitude, similar to
John W. Counts, Madeleine Vickers, Martha (Rebecca) Stokes, Whittney Spivey, Kristina Frank Gardner, Jean Self-Trail, Jared T. Gooley, Ryan J. McAleer, Aaron M. Jubb, David W. Houseknecht, Richard O. Lease, Neil Patrick Griffis, Martin S. Vickers, Kasia Śliwińska, Hannah Gail Dooley Tompkins, Adam M. Hudson

Practical guide to measuring wetland carbon pools and fluxes

Wetlands cover a small portion of the world, but have disproportionate influence on global carbon (C) sequestration, carbon dioxide and methane emissions, and aquatic C fluxes. However, the underlying biogeochemical processes that affect wetland C pools and fluxes are complex and dynamic, making measurements of wetland C challenging. Over decades of research, many observational, experimental, and

Sheel Bansal, Irena F. Creed, Brian Tangen, Scott D. Bridgham, Ankur R. Desai, Ken Krauss, Scott C Neubauer, Gregory B. Noe, Donald O. Rosenberry, Carl C. Trettin, Kimberly Wickland, Scott T. Allen, Ariane Arias-Ortiz, Anna R. Armitage, Dennis Baldocchi, Kakoli Banerjee, David Bastviken, Peter Berg, Matthew J. Bogard, Alex T. Chow, William H. Conner, Christopher Craft, Courtney Creamer, Tonya Delsontro, Jamie Duberstein, Meagan J. Eagle, M. Siobhan Fennessey, Sarah A. Finkelstein, Mathias Goeckede, Sabine Grunwald, Meghan Halibisky, Ellen R. Herbert, Mohammad Jahangir, Olivia Johnson, Miriam C. Jones, Jeffrey Kelleway, Sarah Knox, Kevin D. Kroeger, Kevin Kuehn, David Lobb, Amanda Loder, Shizhou Ma, Damien Maher, Gavin McNicol, Jacob Meier, Beth A. Middleton, Christopher T. Mills, Purbasha Mistry, Abhijith Mitra, Courtney Mobilian, Amanda M. Nahlik, Sue Newman, Jessica O'Connell‬, Patty Oikawa, Max Post van der Burg, Charles A Schutte, Chanchung Song, Camille Stagg, Jessica Turner, Rodrigo Vargas, Mark Waldrop, Markus Wallin, Zhaohui Aleck Wang, Eric Ward, Debra A. Willard, Stephanie A. Yarwood, Xiaoyan Zhu

Geology of the Mount Rogers area, revisited: Evidence of Neoproterozoic continental rifting, glaciation, and the opening and closing of the Iapetus Ocean, Blue Ridge, VA–NC–TN

Recent field and geochronological studies in eight 7.5-minute quadrangles near Mount Rogers in Virginia, North Carolina and Tennessee recognize (1) important stratigraphic and structural relationships for the Neoproterozoic Mount Rogers and Konnarock Formations, and the northeast end of the Mountain City window; (2) the separation of Mesoproterozoic rocks of the Blue Ridge into three age groups; a
Arthur J. Merschat, Ryan J. McAleer, Christopher Holm-Denoma, C. Scott Southworth

Preliminary map of the surface rupture from the August 9, 2020, Mw 5.1 earthquake near Sparta, North Carolina—The Little River fault and other possible coseismic features

This publication is a preliminary map and geodatabase of the coseismic surface rupture and other coseismic features generated from the August 9, 2020, Mw 5.1 earthquake near Sparta, North Carolina. Geologic mapping facilitated by analysis of post-earthquake quality level 0 to 1 lidar, document the coseismic surface rupture, named the Little River fault, and other coseismic features. The Little Riv
Arthur J. Merschat, Mark W. Carter

Implementation plan of the National Cooperative Geologic Mapping Program strategy—Northeast region of the United States: New York and New England

Complexly deformed igneous, metamorphic, and sedimentary rocks form the bedrock of the Northeast region of the United States. Variably thick unconsolidated sediments deposited by glacial, fluvial, and eolian systems locally cover the bedrock. New geologic mapping focuses on areas lacking modern, detailed studies or syntheses, and contributes to existing framework research. This report addresses pl
Gregory J. Walsh, Margaret A. Thomas, Robert G. Marvinney, Stephen B. Mabee, Frederick H. Chormann, Andrew Kozlowski, Marjorie H. Gale, Jon Kim, Brian Savage