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Development of soil radiocarbon profiles in a reactive transport framework

Today, there is a greater appreciation for the importance of the physical protection of carbon (C) through interactions with mineral surfaces, isolation from microbes, and the important role of transport in shaping soil properties and controlling moisture limitations on decomposition. As our paradigm for soil organic carbon (SOC) preservation changes, so too should our representation of the underl
Authors
Jennifer Druhan, Corey Lawrence

Aeolian sediments in paleowetland deposits of the Las Vegas Formation

The Las Vegas Formation (LVF) is a well-characterized sequence of groundwater discharge (GWD) deposits exposed in and around the Las Vegas Valley in southern Nevada. Nearly monolithologic bedrock surrounds the valley, which provides an excellent opportunity to test the hypothesis that GWD deposits include an aeolian component. Mineralogical data indicate that the LVF sediments are dominated by car
Authors
Harland L. Goldstein, Kathleen B. Springer, Jeffrey S. Pigati, Marith C. Reheis, Gary L. Skipp

Oxygen isotopes in terrestrial gastropod shells track Quaternary climate change in the American Southwest

Recent studies have shown the oxygen isotopic composition (δ18O) of modern terrestrial gastropod shells is determined largely by the δ18O of precipitation. This implies that fossil shells could be used to reconstruct the δ18O of paleo-precipitation as long as the isotopic system, including the hydrologic pathways of the local watershed and the gastropod systematics, is well understood. In this stu
Authors
Jason A. Rech, Jeffrey S. Pigati, Kathleen B. Springer, Stephanie Bosch, Jeffrey C. Nekola, Yurena Yanes

Using the Landsat Burned Area products to derive fire history relevant for fire management and conservation in the state of Florida, southeastern USA

Development of comprehensive spatially explicit fire occurrence data remains one of the most critical needs for fire managers globally, and especially for conservation across the southeastern United States. Not only are many endangered species and ecosystems in that region reliant on frequent fire, but fire risk analysis, prescribed fire planning, and fire behavior modeling are sensitive to fire h
Authors
Casey Teske, Melanie K. Vanderhoof, Todd Hawbaker, Joe Noble, J. Kevin Hires

History of Great Salt Lake, Utah, USA: Since the termination of Lake Bonneville

During the past half century or so diverse histories of Great Salt Lake have been written from differing perspectives and all of them have contributed ideas and essential data. The published literature, however, can be confusing and misleading. In this chapter, we review and provide context for a number of those publications. This chapter is intended as a summary of what is known, what is not know
Authors
Charles G. Oviatt, Genevieve Atwood, Robert S. Thompson

8,000 years of climate, vegetation, fire and land-use dynamics in the thermo-mediterranean vegetation belt of northern Sardinia (Italy)

Knowledge about the vegetation history of Sardinia, the second largest island of the Mediterranean, is scanty. Here, we present a new sedimentary record covering the past ~ 8,000 years from Lago di Baratz, north-west Sardinia. Vegetation and fire history are reconstructed by pollen, spores, macrofossils and charcoal analyses and environmental dynamics by high-resolution element geochemistry togeth
Authors
Tiziana Pedrotta, Erika Gobet, Christoph Schwörer, Giorgia Beffa, Christoph Butz, Paul D. Henne, César Morales-Molino, Salvatore Pasta, Jacqueline Van Leeuwen, Hendrik Vogel, Elias Zwimpfer, Flavio Anselmetti, Martin Grosjean, Willy Tinner

Implementation plan for the southern Pacific Border and Sierra-Cascade Mountains provinces

IntroductionThe National Cooperative Geologic Mapping Program (NCGMP) is publishing a strategic plan titled Renewing the National Cooperative Geologic Mapping Program as the Nation’s Authoritative Source for Modern Geologic Knowledge (Brock and others, in press). The plan provides a vision, mission, and goals for the program during the years 2020–2030, which are:Vision.—Create an integrated, three
Authors
Victoria E. Langenheim, Russell W. Graymer, Robert E. Powell, Kevin M. Schmidt, Donald S. Sweetkind

Postcaldera intrusive magmatism at the Platoro caldera complex, Southern Rocky Mountain volcanic field, Colorado, USA

The Oligocene Platoro caldera complex of the San Juan volcanic locus in Colorado (USA) features numerous exposed plutons both within the caldera and outside its margins, enabling investigation of the timing and evolution of postcaldera magmatism. Intrusion whole-rock geochemistry and phenocryst and/or mineral trace element compositions coupled with new zircon U-Pb geo-chronology and zircon in situ
Authors
Amy K. Gilmer, Ren A. Thompson, Peter W. Lipman, Jorge A. Vazquez, Amanda (Kate) Souders

Renewing the National Cooperative Geologic Mapping Program as the Nation’s authoritative source for modern geologic knowledge

This document presents the renewed vision, mission, and goals for the National Cooperative Geologic Mapping Program (NCGMP). The NCGMP, as authorized by the National Cooperative Geologic Mapping Act of 1992 (Public Law 102-285, 106 Stat. 166 and its reauthorizations), is tasked with expediting the production of a geologic database for the Nation based on modern geologic maps and their supporting d
Authors
John Brock, Karen Berry, James Faulds, Richard Berg, Kyle House, Michael Marketti, Darcy McPhee, Kevin M. Schmidt, James Schmitt, David R. Soller, David Spears, Ren A. Thompson, Harvey Thorleifson, Gregory J. Walsh

Landscape evolution in eastern Chuckwalla Valley, Riverside County, California

This study investigates sedimentary and geomorphic processes in eastern Chuckwalla Valley, Riverside County, California, a region of arid, basin-and-range terrain where extensive solar-energy development is planned. The objectives of this study were to (1) measure local weather parameters and use them to model aeolian sediment-transport potential; (2) identify surface sedimentary characteristics i
Authors
Amy E. East, Harrison J. Gray, Margaret Hiza Redsteer, Matthew Ballmer

The changes in species composition mediate direct effects of climate change on future fire regimes of boreal forests in northeastern China

Direct effects of climate change (i.e. temperature rise, changes in seasonal precipitation, wind patterns and atmospheric stability) affect fire regimes of boreal forests by altering fire behaviour, fire seasons and fuel moisture. Climate change also alters species composition and fuel characteristics, which subsequently alter fire regimes. However, indirect effects of climate change are often sim
Authors
Chao Huang, Hong S. He, Yu Liang, Todd Hawbaker, Paul D. Henne, Wenru Xu, Peng Gong, Zhiliang Zhu

Beach placer mineral deposits along localized paleoshorelines of the western Interior Seaway, upper cretaceous Fox Hills sandstone, eastern Denver Basin, Colorado

Beach placers deposited within the Fox Hills Sandstone along the eastern flank of the Denver Basin contain minerals deemed critical in 2018 by the U.S. Department of the Interior. These marine beach placers, or paleoplacers, were deposited in the Late Cretaceous along the western edge of the retreating Western Interior Seaway (WIS). Preliminary investigations determined that these deposits contain
Authors
Michael K O'Keeffe, Marieke Dechesne, Matthew J. Morgan, Stephen M Keller, Katherina Pfaff, Asha Mahatma, Alexander I Peretyatko