Publications
Filter Total Items: 1493
On the importance of stratigraphic control for vertebrate fossil sites in Channel Islands National Park, California, USA: Examples from new Mammuthus finds on San Miguel Island On the importance of stratigraphic control for vertebrate fossil sites in Channel Islands National Park, California, USA: Examples from new Mammuthus finds on San Miguel Island
Quaternary vertebrate fossils, most notably mammoth remains, are relatively common on the northern Channel Islands of California. Well-preserved cranial, dental, and appendicular elements of Mammuthus exilis (pygmy mammoth) and Mammuthus columbi (Columbian mammoth) have been recovered from hundreds of localities on the islands during the past half-century or more. Despite this...
Authors
Jeffery S. Pigati, Daniel R. Muhs, John P. McGeehin
Testing fault growth models with low-temperature thermochronology in the northwest Basin and Range, USA Testing fault growth models with low-temperature thermochronology in the northwest Basin and Range, USA
Common fault growth models diverge in predicting how faults accumulate displacement and lengthen through time. A paucity of field-based data documenting the lateral component of fault growth hinders our ability to test these models and fully understand how natural fault systems evolve. Here we outline a framework for using apatite (U-Th)/He thermochronology (AHe) to quantify the along...
Authors
Magdalena A. E. Curry, Jason B. Barnes, Joseph P. Colgan
Field guide to Laramide basin evolution and drilling activity in North Park and Middle Park, Colorado Field guide to Laramide basin evolution and drilling activity in North Park and Middle Park, Colorado
Overview of the geologic history of the North Park–Middle Park area and its past and recent drilling activity. Field trip stops highlight basin formation and the consequences of geologic configuration on oil and gas plays and development. The starting point is the west flank of the Denver Basin to compare and contrast the latest Cretaceous through Eocene basin fill on both flanks of the...
Authors
Marieke Dechesne, James C. Cole, Christopher B. Martin
Latest Pleistocene and Holocene glacial events in the Colonia valley, Northern Patagonia Icefield, southern Chile Latest Pleistocene and Holocene glacial events in the Colonia valley, Northern Patagonia Icefield, southern Chile
The Northern Patagonia Icefield (NPI) is the primary glaciated terrain worldwide at its latitude (46.5–47.5°S), and constraining its glacial history provides unique information for reconstructing Southern Hemisphere paleoclimate. The Colonia Glacier is the largest outlet glacier draining the eastern NPI. Ages were determined using dendrochronology, lichenometry, radiocarbon, cosmogenic...
Authors
David A. Nimick, Daniel Mcgrath, Shannon A. Mahan, Beverly A. Friesen, Jonathan Leidich
U.S. Geological Survey science for the Wyoming Landscape Conservation Initiative—2015 annual report U.S. Geological Survey science for the Wyoming Landscape Conservation Initiative—2015 annual report
This is the eighth annual report highlighting U.S. Geological Survey (USGS) science and decision-support activities conducted for the Wyoming Landscape Conservation Initiative (WLCI). The activities address specific management needs identified by WLCI partner agencies. In 2015, USGS scientists continued 24 WLCI projects in 5 categories: (1) acquiring and analyzing resource-condition data...
Authors
Zachary H. Bowen, Cameron L. Aldridge, Patrick J. Anderson, Timothy J. Assal, Timothy T. Bartos, Anna D. Chalfoun, Geneva W. Chong, Marie K. Dematatis, Cheryl A. Eddy-Miller, Steven L. Garman, Stephen S. Germaine, Collin G. Homer, Matthew J. Kauffman, Christopher C. Huber, Daniel J. Manier, Cynthia P. Melcher, Kirk A. Miller, Tamar Norkin, Lindsey E. Sanders, Annika W. Walters, Anna B. Wilson, Teal B. Wyckoff
Status and trends of land change in the Eastern United States—1973 to 2000 Status and trends of land change in the Eastern United States—1973 to 2000
Preface U.S. Geological Survey (USGS) Professional Paper 1794–D is the fourth in a four-volume series on the status and trends of the Nation’s land use and land cover, providing an assessment of the rates and causes of land-use and land-cover change in the Eastern United States between 1973 and 2000. Volumes A, B, and C provide similar analyses for the Western United States, the Great...
Quaternary geologic map of the Wolf Point 1° × 2° quadrangle, Montana and North Dakota Quaternary geologic map of the Wolf Point 1° × 2° quadrangle, Montana and North Dakota
The Wolf Point quadrangle encompasses approximately 16,084 km2 (6,210 mi2). The northern boundary is the Montana/Saskatchewan (U.S.-Canada) boundary. The quadrangle is in the Northern Plains physiographic province and it includes the Peerless Plateau and Flaxville Plain. The primary river is the Missouri River. The map units are surficial deposits and materials, not landforms. Deposits...
Authors
David S. Fullerton, Roger B. Colton, Charles A. Bush
Holocene paleoclimate inferred from salinity histories of adjacent lakes in southwestern Sicily (Italy) Holocene paleoclimate inferred from salinity histories of adjacent lakes in southwestern Sicily (Italy)
Marked uncertainties persist regarding the climatic evolution of the Mediterranean region during the Holocene. For instance, whether moisture availability gradually decreased, remained relatively constant, or increased during the last 7000 years remains a matter of debate. To assess Holocene limnology, hydrology and moisture dynamics, the coastal lakes Lago Preola and Gorgo Basso...
Authors
B Brandon Curry, Paul D. Henne, Francesc Mezquita-Joanes, Federico Marrone, Valentina Pieri, Tommaso La Mantia, Camilla Calo, Willy Tinner
Iron oxide minerals in dust-source sediments from the Bodélé Depression, Chad: Implications for radiative properties and Fe bioavailability of dust plumes from the Sahara Iron oxide minerals in dust-source sediments from the Bodélé Depression, Chad: Implications for radiative properties and Fe bioavailability of dust plumes from the Sahara
Atmospheric mineral dust can influence climate and biogeochemical cycles. An important component of mineral dust is ferric oxide minerals (hematite and goethite) which have been shown to influence strongly the optical properties of dust plumes and thus affect the radiative forcing of global dust. Here we report on the iron mineralogy of dust-source samples from the Bodélé Depression...
Authors
Bruce M. Moskowitz, Richard L. Reynolds, Harland L. Goldstein, Thelma Beroquo, Raymond F. Kokaly, Charlie S Bristow
Toward an integrated understanding of perceived biodiversity values and environmental conditions in a national park Toward an integrated understanding of perceived biodiversity values and environmental conditions in a national park
In spatial planning and management of protected areas, increased priority is being given to research that integrates social and ecological data. However, public viewpoints of the benefits provided by ecosystems are not easily quantified and often implicitly folded into natural resource management decisions. Drawing on a spatially explicit participatory mapping exercise and a Social...
Authors
Carena J. van Riper, Gerard T. Kyle, Benson C. Sherrouse, Kenneth J. Bagstad, Stephen G. Sutton
Evaluating alternative methods for biophysical and cultural ecosystem services hotspot mapping in natural resource planning Evaluating alternative methods for biophysical and cultural ecosystem services hotspot mapping in natural resource planning
Context Data for biophysically modeled and Public Participatory GIS (PPGIS)-derived cultural ecosystem services have potential to identify natural resource management synergies and conflicts, but have rarely been combined. Ecosystem service hot/coldspots generated using different methods vary in their spatial extent and connectivity, with important implications. Objectives We map...
Authors
Kenneth J. Bagstad, Darius J. Semmens, Zachary H. Ancona, Benson C. Sherrouse
Total belowground carbon flux in subalpine forests is related to leaf area index, soil nitrogen, and tree height Total belowground carbon flux in subalpine forests is related to leaf area index, soil nitrogen, and tree height
In forests, total belowground carbon (C) flux (TBCF) is a large component of the C budget and represents a critical pathway for delivery of plant C to soil. Reducing uncertainty around regional estimates of forest C cycling may be aided by incorporating knowledge of controls over soil respiration and TBCF. Photosynthesis, and presumably TBCF, declines with advancing tree size and age...
Authors
Erin Michele Berryman, Michael G. Ryan, John B. Bradford, Todd Hawbaker, R. Birdsey