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U.S. Geological Survey Science for the Wyoming Landscape Conservation Initiative - 2013 Annual Report U.S. Geological Survey Science for the Wyoming Landscape Conservation Initiative - 2013 Annual Report
This is the sixth report produced by the U.S. Geological Survey (USGS) for the Wyoming Landscape Conservation Initiative (WLCI) to detail annual activities conducted by USGS for addressing specific management needs identified by WLCI partners. In FY2013, there were 25 ongoing and new projects conducted by the USGS. These projects fall into 8 major categories: (1) synthesizing and...
Authors
Zachary H. Bowen, Cameron L. Aldridge, Patrick J. Anderson, Timothy J. Assal, Carleton R. Bern, Laura R Biewick, Gregory K. Boughton, Anna D. Chalfoun, Geneva W. Chong, Marie K. Dematatis, Bradley C. Fedy, Steven L. Garman, Steve Germaine, Matthew G. Hethcoat, Collin G. Homer, Christopher Huber, Matthew J. Kauffman, Natalie Latysh, Daniel J. Manier, Cynthia P. Melcher, Kirk A. Miller, Christopher J. Potter, Spencer Schell, Michael J. Sweat, Annika W. Walters, Anna B. Wilson
Age and isotopic systematics of Cretaceous borehole and surface samples from the greater Los Angeles Basin region: Implications for the types of crust that might underlie Los Angeles and their distribution along late Cenozoic fault systems Age and isotopic systematics of Cretaceous borehole and surface samples from the greater Los Angeles Basin region: Implications for the types of crust that might underlie Los Angeles and their distribution along late Cenozoic fault systems
Nine U-Pb zircon ages were determined on plutonic rocks sampled from surface outcrops and rock chips of drill core from boreholes within the greater Los Angeles Basin region. In addition, lead-strontium-neodymium (Pb-Sr-Nd) whole-rock isotopic data were obtained for eight of these samples. These results help to characterize the crystalline basement rocks hidden in the subsurface and...
Authors
Wayne R. Premo, Douglas M. Morton, Ronald W. Kistler
The misconception of ecosystem disservices: How a catchy term may yield the wrong messages for science and society The misconception of ecosystem disservices: How a catchy term may yield the wrong messages for science and society
In their recent article, Shapiro and Báldi (2014) build on the long-running narrative of “ecosystem services and disservices” (e.g., Zhang et al., 2007 ; Lyytimäki et al., 2008), describing how nature yields both benefits and harms to society. These harms include crop pests, floods, landslides, wildfires, and zoonotic disease transmission, among others. While we agree with their argument...
Authors
Ferdinando Villa, Kenneth J. Bagstad, Brian Voigt, Gary W. Johnson, Ioannis N Athanasiadis, Stefano Balbi
Applying threshold concepts to conservation management of dryland ecosystems: Case studies on the Colorado Plateau Applying threshold concepts to conservation management of dryland ecosystems: Case studies on the Colorado Plateau
Ecosystems may occupy functionally distinct alternative states, some of which are more or less desirable from a management standpoint. Transitions from state to state are usually associated with a particular trigger or sequence of triggers, such as the addition or subtraction of a disturbance. Transitions are often not linear, rather it is common to see an abrupt transition come about...
Authors
Matthew A. Bowker, Mark E. Miller, Steven L. Garman, Travis Belote
Pb-Sr-Nd-O isotopic characterization of Mesozoic rocks throughout the northern end of the Peninsular Ranges batholith: Isotopic evidence for the magmatic evolution of oceanic arc–continental margin accretion during the Late Cretaceous of southern Californ Pb-Sr-Nd-O isotopic characterization of Mesozoic rocks throughout the northern end of the Peninsular Ranges batholith: Isotopic evidence for the magmatic evolution of oceanic arc–continental margin accretion during the Late Cretaceous of southern Californ
Within the duration of the U.S. Geological Survey (USGS)–based Southern California Areal Mapping Project (SCAMP), many samples from the northern Peninsular Ranges batholith were studied for their whole-rock radioisotopic systematics (rubidium-strontium [Rb-Sr], uranium-thorium-lead [U-Th-Pb], and samarium-neodymium [Sm-Nd]), as well as oxygen (O), a stable isotope. The results of three...
Authors
Ronald W. Kistler, Joseph L. Wooden, Wayne R. Premo, Douglas M. Morton
U-Pb zircon geochronology of plutonism in the northern Peninsular Ranges batholith, southern California: Implications for the Late Cretaceous tectonic evolution of southern California U-Pb zircon geochronology of plutonism in the northern Peninsular Ranges batholith, southern California: Implications for the Late Cretaceous tectonic evolution of southern California
Utilizing both sensitive high-resolution ion microprobe (SHRIMP) and conventional isotope dilution–thermal ionization mass spectrometry (ID-TIMS) methods, crystallization and/or emplacement ages have been obtained for a suite of Cretaceous intermediate-composition plutonic samples collected along a roughly E-W–trending traverse through the northern Peninsular Ranges batholith. Previously...
Authors
Wayne R. Premo, Douglas M. Morton, Joseph L. Wooden, C. Mark Fanning
Geomorphic evidence for enhanced Pliocene-Quaternary faulting in the northwestern Basin and Range Geomorphic evidence for enhanced Pliocene-Quaternary faulting in the northwestern Basin and Range
Mountains in the U.S. Basin and Range Province are similar in form, yet they have different histories of deformation and uplift. Unfortunately, chronicling fault slip with techniques like thermochronology and geodetics can still leave sizable, yet potentially important gaps at Pliocene–Quaternary (∼105–106 yr) time scales. Here, we combine existing geochronology with new geomorphic...
Authors
Magdalena A Ellis, Barnes Jason B, Joseph P. Colgan
The changing southwest The changing southwest
This chapter describes important geographical and socio-economic characteristics and trends in the Southwest—such as population and economic growth and changes in land ownership, land use, and land cover—that provide the context for how climate change will likely affect the Southwest. The chapter also describes key laws and institutions relevant to adaptive management of resources.
Authors
David M. Theobald, William Travis, Mark A. Drummond, Eric Gordon, Michelle Betsill
Digital-image processing and image analysis of glacier ice Digital-image processing and image analysis of glacier ice
This document provides a methodology for extracting grain statistics from 8-bit color and grayscale images of thin sections of glacier ice—a subset of physical properties measurements typically performed on ice cores. This type of analysis is most commonly used to characterize the evolution of ice-crystal size, shape, and intercrystalline spatial relations within a large body of ice...
Authors
Joan J. Fitzpatrick
Wyoming Basin Rapid Ecoregional Assessment: Work Plan Wyoming Basin Rapid Ecoregional Assessment: Work Plan
The overall goal of the Rapid Ecoregional Assessments (REAs) being conducted for the Bureau of Land Management (BLM) is to provide information that supports regional planning and analysis for the management of ecological resources. The REA provides an assessment of baseline ecological conditions, an evaluation of current risks from drivers of ecosystem change, and a predictive capacity...
Authors
Natasha B. Carr, Steven L. Garman, Annika Walters, Andrea Ray, Cynthia P. Melcher, Jeff S. Wesner, Michael S. O’Donnell, Kirk R. Sherrill, Nils C. Babel, Zachary H. Bowen
Loess origin, transport, and deposition over the past 10,000 years, Wrangell-St. Elias National Park, Alaska Loess origin, transport, and deposition over the past 10,000 years, Wrangell-St. Elias National Park, Alaska
Contemporary glaciogenic dust has not received much attention, because most research has been on glaciogenic dust of the last glacial period or non-glaciogenic dust of the present interglacial period. Nevertheless, dust from modern glaciogenic sources may be important for Fe inputs to primary producers in the ocean. Adjacent to the subarctic Pacific Ocean, we studied a loess section near...
Authors
Daniel R. Muhs, James R. Budahn, John P. McGeehin, E. Arthur Bettis, Gary L. Skipp, James B. Paces, Elisabeth A. Wheeler
Geochronology and paleoenvironment of pluvial Harper Lake, Mojave Desert, California, USA Geochronology and paleoenvironment of pluvial Harper Lake, Mojave Desert, California, USA
Accurate reconstruction of the paleo-Mojave River and pluvial lake (Harper, Manix, Cronese, and Mojave) system of southern California is critical to understanding paleoclimate and the North American polar jet stream position over the last 500 ka. Previous studies inferred a polar jet stream south of 35°N at 18 ka and at ~ 40°N at 17–14 ka. Highstand sediments of Harper Lake, the upstream...
Authors
Anna L. Garcia, Jeffrey R. Knott, Shannon Mahan, Jordan Bright