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Not all publications have extents, not all extents are completely accurate
The Alaska convergent margin backstop splay fault zone, a potential large tsunami generator between the frontal prism and continental framework
Roland von Huene, John J. Miller, Anne Krabbenhoeft
2021, Geochemistry, Geophysics, and Geosystems (22)
The giant tsunami that swept the Pacific from Alaska to Antarctica in 1946 was generated along one of three Alaska Trench instrumentally recorded aftershock areas following great and giant earthquakes. Aftershock areas were investigated during the past decade with multibeam bathymetry, ocean bottom seismograph wide‐angle seismic, reprocessed legacy, and new...
Permafrost promotes shallow groundwater flow and warmer headwater streams
Ylva Sjöberg, Adam K. Janke, S Painter, E. Coonradt, Michael P. Carey, Jonathan A. O'Donnell, Joshua C. Koch
2021, Water Resources Research (57)
The presence of permafrost influences the flow paths of water through Arctic landscapes and thereby has the potential to impact stream discharge and thermal regimes. Observations from eleven headwater streams in Alaska showed that July water temperatures were higher in catchments with more near‐surface permafrost. We apply a fully coupled...
Shifts in the wintering distribution and abundance of Emperor Geese in Alaska
Brian D. Uher-Koch, Raymond M. Buccheit, Charles R. Eldermire, Heather M. Wilson, Joel A. Schmutz
2021, Global Ecology and Conservation (25)
For wildlife species that winter at northern latitudes, harsh overwinter conditions can play an important role in population dynamics. Recent changes in global temperatures have resulted in distributional shifts of wildlife species, as well as amelioration of winter climates in northern...
Dating by cosmogenic nuclides
Paul R. Bierman, Adrian Bender, Andrew J. Christ, Lee B. Corbett, Christopher T. Halsted, Eric W. Portenga, Amanda H. Schmidt
2021, Book chapter, Encyclopedia of geology
Since the 1990s, cosmogenic nuclides have revolutionized the study of Earth surface processes, particularly the understanding of rates and dates. These nuclides, including 3He, 10Be, 14C, 21Ne, 26Al, and 36Cl, enable dating of landforms and the measurement of erosion rates both at the scale of drainage basins and at specific locations on Earth's surface. Cosmogenic nuclides are produced...
Basalt geochemistry and mantle flow during early backarc basin evolution: Havre Trough and Kermadec Arc, southwest Pacific
James B Gill, Kaj Hoernle, Erin Todd, Folkmar Hauff, Reinhard Werner, Christian Timm, Dieter Garbe-Schönberg, Marcus Gutjahr
2021, Geochemistry Geophysics Geosystems (22)
The Havre Trough (HT) backarc basin in the southwest Pacific is in the rifting stage of development. We distinguish five types of basalt there based on their amount and kind of slab component: backarc basalts (BAB) with little or no slab component, modified BAB with slight amounts,...
Record fledging count from a seven-egg clutch in the Cooper’s Hawk (Accipiter cooperii)
Robert N. Rosenfield, Sarah A. Sonsthagen, Ann Elizabeth Riddle-Berntsen, Evan Kuhel
2021, Wilson Journal of Ornithology (132) 460-463
Cooper's Hawks (Accipiter cooperii) typically lay 3–5 eggs per clutch, rarely 6 eggs, and there are 2 accounts of 7-egg clutches and 1 record of a maximum 8-egg clutch for the species. Brood sizes of 3–5 young are common and the previous maximum brood count is 6 young. However, in...
Generation of calc-alkaline magmas during crystallization at high oxygen fugacity: An experimental and petrologic study of tephras from Buldir Volcano, western Aleutian Arc, Alaska, USA
Laura Waters, Elizabeth Cottrell, Michelle L. Coombs, Katherine A. Kelley
2021, Journal of Petrology (62)
Despite agreement that calc-alkaline volcanism occurs at subduction zones and is responsible for the genesis of continental landmasses, there is no consensus on the source of the Fe-depleted signature hallmark to calc-alkaline volcanism. In this study, we utilize mafic tephras collected from Buldir Volcano to address the genesis of...
Multiple physical properties of gas hydrate-bearing sediments recovered from Alaska North Slope 2018 Hydrate-01 Stratigraphic Test Well
Jun Yoneda, Yusuke Jin, Michihiro Muraoka, Motoi Oshima, Kiyofumi Suzuki, Mike Walker, Donald Westacott, Satoshi Otsuki, Kenichi Kumagai, Timothy Collett, Ray Boswell, Norihiro Okinaka
2021, Journal of Marine and Petroleum Geology (123)
Knowledge of the petrophysical and geomechanical properties of gas hydrate-bearing sediments is essential for predicting reservoir responses to gas production from gas hydrate reservoirs. In December 2018, Stratigraphic Test Well Hydrate-01 was drilled in the western part of the Prudhoe Bay...
Seabird‐induced natural mortality of forage fish varies with fish abundance: Evidence from five ecosystems
Claire Saraux, William J. Sydeman, John F. Piatt, Tycho Anker-Nilssen, Jonas Hentati-Sundberg, Sophie Bertrand, Philippe M. Cury, Robert W. Furness, James A. Miller, Henrik Österblom, Giannina Passuni, Jean-Paul Roux, Lynne Shannon, Robert J.M. Crawford
2021, Fish and Fisheries (22) 262-279
Forage fish populations often undergo large and rapid fluctuations in abundance. However, most of their predators are buffered against such fluctuations owing to their slower pace of life, which allows them to maintain more stable populations, at least during short periods of food scarcity. In this...
Aufeis fields as novel groundwater-dependent ecosystems in the arctic cryosphere
Alexander D. Huryn, M. Gooseff, P. Hendrickson, Martin A. Briggs, K. Tape, Neil C. Terry
2021, Limnology and Oceanography (66) 607
River aufeis (ow′ fīse) are widespread features of the arctic cryosphere. They form when river channels become locally restricted by ice, resulting in cycles of water overflow and freezing and the accumulation of ice, with some aufeis attaining areas of ~ 25 + km2 and thicknesses of 6+ m. During winter, unfrozen sediments beneath the insulating ice layer provide perennial...
Environmental gradients of selection for an alpine-obligate bird, the white-tailed ptarmigan (Lagopus leucura)
Shawna J Zimmerman, Cameron L. Aldridge, Kathryn M. Langin, Gregory T Wann, Robert S. Cornman, Sara J. Oyler-McCance
2021, Heredity (126) 117-131
The warming climate will expose alpine species adapted to a highly seasonal, harsh environment to novel environmental conditions. A species can shift their distribution, acclimate, or adapt in response to a new climate. Alpine species have little suitable habitat to shift their distribution, and the limits of acclimation will likely...
Lake trout growth is sensitive to spring temperature in southwest Alaska lakes
Vanessa R. von Biela, Bryan A. Black, Daniel B. Young, Peter van der Sleen, Krista K. Bartz, Christian E. Zimmerman
2021, Ecology of Freshwater Fish (30) 88-99
In high‐latitude lakes, air temperature is an important driver of ice cover thickness and duration, which in turn influence water temperature and primary production supporting lake consumers and predators. In lieu of multidecadal observational records necessary to assess the response of lakes to long‐term warming, we used otolith‐based growth records...
Focus areas for data acquisition for potential domestic resources of 11 critical minerals in Alaska—Aluminum, cobalt, graphite, lithium, niobium, platinum group elements, rare earth elements, tantalum, tin, titanium, and tungsten, chap. C of U.S. Geological Survey, Focus areas for data acquisition for potential domestic sources of critical minerals
Douglas C. Kreiner, James V. Jones III
2020, Open-File Report 2019-1023-C
Phase 2 of the Earth Mapping Resources Initiative (Earth MRI) focuses on geologic belts that are favorable for hosting mineral systems that may contain select critical minerals. Phase 1 of the Earth MRI program focused on rare earth elements (REE), and phase 2 adds aluminum, cobalt, graphite, lithium, niobium, platinum-group...
Focus areas for data acquisition for potential domestic resources of 11 critical minerals in the conterminous United States, Hawaii, and Puerto Rico—Aluminum, cobalt, graphite, lithium, niobium, platinum-group elements, rare earth elements, tantalum, tin, titanium, and tungsten
Jane M. Hammarstrom, Connie L. Dicken, Warren C. Day, Albert H. Hofstra, Benjamin J. Drenth, Anjana K. Shah, Anne E. McCafferty, Laurel G. Woodruff, Nora K. Foley, David A. Ponce, Thomas P. Frost, Lisa L. Stillings
2020, Open-File Report 2019-1023-B
In response to a need for information on potential domestic sources of critical minerals, the Earth Mapping Resources Initiative (Earth MRI) was established to identify and prioritize areas for acquisition of new geologic mapping, geophysical data, and elevation data to improve our knowledge of the geologic framework of the United...
Seismic monitoring & response for the Trans-Alaska Pipeline System
S Strait, David J. Wald
2020, Conference Paper
The 800-mile Trans Alaska Pipeline System (TAPS) passes through extremely remote regions, where there is a high potential for seismic activity. Alyeska Pipeline Service Company, the TAPS operator, has been on the forefront of seismic engineering and situational awareness, and continues to enhance its capabilities. TAPS has used earthquake monitoring...
Juvenile Coho and Chinook salmon growth, size, and condition linked to watershed-scale salmon spawner abundance
Philip J. Joy, Craig A. Stricker, Renae Ivanoff, Shiao Y. Wang, Mark S. Wipfli, Andrew C. Seitz, Jiaqi Huang, Mathew B. Tyers
2020, Transactions of the American Fisheries Society (150) 307-326
Anadromous Pacific salmon Oncorhynchus spp. are semelparous, and resource subsidies from spawning adult salmon (marine-derived nutrients [MDN]) benefit juvenile salmonids while they rear in freshwater. However, it is unclear if juvenile salmon populations respond predictably to the abundance of spawning salmon at the watershed scale. To address whether hypothesized benefits to rearing...
Vapor-bubble growth in olivine-hosted melt inclusions
Daniel J. Rasmussen, Terry Plank, Paul J. Wallace, Megan Newcombe, Jacob B. Lowenstern
2020, American Mineralogist (105) 1898-1919
Melt inclusions record the depth of magmatic processes, magma degassing paths, and volatile budgets of magmas. Extracting this information is a major challenge. It requires determining melt volatile contents at the time of entrapment when working with melt inclusions that have suffered post-entrapment modifications. Several processes decrease internal melt inclusion...
Changing storm conditions in response to projected 21st century climate change and the potential impact on an arctic barrier island–lagoon system—A pilot study for Arey Island and Lagoon, eastern Arctic Alaska
Li H. Erikson, Ann E. Gibbs, Bruce M. Richmond, Curt D. Storlazzi, Benjamin M. Jones, Karin Ohman
2020, Open-File Report 2020-1142
Executive SummaryArey Lagoon, located in eastern Arctic Alaska, supports a highly productive ecosystem, where soft substrate and coastal wet sedge fringing the shores are feeding grounds and nurseries for a variety of marine fish and waterfowl. The lagoon is partially protected from the direct onslaught of Arctic Ocean waves by...
Effects of fish populations on Pacific Loon (Gavia pacifica) and Yellow-billed Loon (G. adamsii) lake occupancy and chick production in northern Alaska
Brian D. Uher-Koch, Kenneth G. Wright, Hannah R. Uher-Koch, Joel A. Schmutz
2020, Arctic (73) 405-550
Predator populations are vulnerable to changes in prey distribution or availability. With warming temperatures, lake ecosystems in the Arctic are predicted to change in terms of hydrologic flow, water levels, and connectivity with other lakes. We surveyed lakes in northern Alaska to understand how shifts in the...
Alaska and Landsat
U.S. Geological Survey
2020, Fact Sheet 2020-3068
Alaska’s landscapes are changing at a more rapid rate than those of the lower 48. Its large size makes the collection of aerial surveys—a biannual occurrence for the conterminous United States—cost-prohibitive. That means the Landsat series of land imaging satellites offer the only publicly available, up-to-date imagery of land conditions...
Permafrost mapping with electrical resistivity tomography in two wetland systems north of the Tanana River, Interior Alaska
Christopher H. Conaway, Cordell Johnson, Thomas Lorenson, Merritt R. Turetsky, Eugénie S. Euskirchen, Mark Waldrop, Peter W. Swarzenski
2020, Journal of Environmental & Engineering Geophysics (2) 199-209
Surface-based 2D electrical resistivity tomography (ERT) surveys were used to characterize permafrost distribution at wetland sites on the alluvial plain north of the Tanana River, 20 km southwest of Fairbanks, Alaska, in June and September 2014. The sites were part of an ecologically-sensitive research area characterizing biogeochemical response of this...
2017 Volcanic activity in Alaska—Summary of events and response of the Alaska Volcano Observatory
James P. Dixon, Cheryl E. Cameron, Alexandra M. Iezzi, John A. Power, Kristi L. Wallace, Christopher F. Waythomas
2020, Scientific Investigations Report 2020-5102
The Alaska Volcano Observatory responded to eruptions, significant and minor volcanic unrest, and seismic events at 16 volcanic centers in Alaska during 2017. The most notable volcanic activity consisted of a major eruption at Bogoslof Island, continuing intermittent dome growth and ash eruptions from Mount Cleveland, the end of the...
2016 Volcanic activity in Alaska—Summary of events and response of the Alaska Volcano Observatory
Cheryl E. Cameron, James P. Dixon, Christopher F. Waythomas, Alexandra M. Iezzi, Kristi L. Wallace, Robert G. McGimsey, Katharine F. Bull
2020, Scientific Investigations Report 2020-5125
The Alaska Volcano Observatory responded to eruptions, volcanic unrest or suspected unrest, and seismic events at 15 volcanic centers in Alaska during 2016. The most notable volcanic activity consisted of eruptions at Pavlof and Bogoslof volcanoes. Both eruptions produced significant ash clouds that affected regional air travel. Mount Cleveland continued...
Cretaceous to Oligocene magmatic and tectonic evolution of the western Alaska Range: Insights from U-Pb and 40Ar/39Ar geochronology
James V. Jones III, Erin Todd, Stephen E. Box, Peter J. Haeussler, Christopher S. Holm-Denoma, Susan M. Karl, Garth E. Graham, Dwight Bradley, Andrew R.C. Kylander-Clark, Richard M. Friedman, Paul W. Layer
2020, Geosphere (17) 118-153
New U-Pb and 40Ar/39Ar ages integrated with geologic mapping and observations across the western Alaska Range constrain the distribution and tectonic setting of Cretaceous to Oligocene magmatism along an evolving accretionary plate margin in south-central Alaska. These rocks were emplaced across basement domains that include Neoproterozoic...