Natural versus anthropogenic dispersion of metals to the environment in the Wulik River area, western Brooks Range, northern Alaska
K.D. Kelley, T. Hudson
2007, Geochemistry: Exploration, Environment, Analysis (7) 87-96
Zinc-lead-silver mineral deposits in the Wulik River region, Alaska, contain an enormous accumulation of Zn. In addition to the giant deposits at Red Dog, at least nine other deposits are known. Natural weathering of these deposits has dispersed metals over a wide region over a long period of time (c....
Shorebird abundance and distribution on the coastal plain of the Arctic National Wildlife Refuge
S. Brown, J. Bart, Richard B. Lanctot, J. A. Johnson, S. Kendall, D. Payer, J. Johnson
2007, Condor (109) 1-14
The coastal plain of the Arctic National Wildlife Refuge hosts seven species of migratory shorebirds listed as highly imperiled or high priority by the U.S. Shorebird Conservation Plan and five species listed as Birds of Conservation Concern by the U.S. Fish and Wildlife Service. During the first comprehensive shorebird survey...
Nesting ecology of boreal forest birds following a massive outbreak of spruce beetles
Steven M. Matsuoka, Colleen M. Handel
2007, Journal of Wildlife Management (71) 51-63
We studied breeding dark-eyed juncos (Junco hyemalis), yellow-rumped warblers (Dendroica coronata), and spruce-nesting birds from 1997 to 1998 among forests with different levels of spruce (Picea spp.) mortality following an outbreak of spruce beetles (Dendroctonus rufipennis) in Alaska, USA. We identified species using live and beetle-killed spruce for nest sites and...
Holocene slip rate and revised characteristic earthquake parameters for the western segment of the Castle Mountain fault, Alaska
Julie B. Willis, Peter J. Haeussler, Ronald L. Bruhn, Grant C. Willis
2007, Bulletin of the Seismological Society of America (97) 1019-1024
The western segment of the Castle Mountain fault poses a significant seismic hazard to the most populated region of south-central Alaska. We identify a previously unrecognized margin of a postglacial outwash channel that is offset right laterally 36 ± 4 m across the western segment of the Castle Mountain fault....
North to Alaska: Evidence for conveyor belt transport of Dungeness crab larvae along the west coast of the United States and Canada
W. Park, David C. Douglas, Thomas C. Shirley
2007, Limnology and Oceanography (52) 248-256
We propose and evaluate the hypothesis that Dungeness crab (Cancer magister) larvae from the northwestern coast of the United States and Canada can be transported northward to southeastern Alaska. Larvae collected in southeastern Alaska during May and June 1997–2004 had abundances and stages that varied seasonally, interannually, and spatially. An...
Net emissions of CH4 and CO2 in Alaska: Implications for the region's greenhouse gas budget
Q. Zhuang, J. M. Melillo, A. D. McGuire, D. W. Kicklighter, R.G. Prinn, P.A. Steudler, B.S. Felzer, S. Hu
2007, Ecological Applications (17) 203-212
We used a biogeochemistry model, the Terrestrial Ecosystem Model (TEM), to study the net methane (CH4) fluxes between Alaskan ecosystems and the atmosphere. We estimated that the current net emissions of CH4 (emissions minus consumption) from Alaskan soils are ???3 Tg CH 4/yr. Wet tundra ecosystems are responsible for 75%...
Spawning distribution of sockeye salmon in a glacially influenced watershed: The importance of glacial habitats
Daniel B. Young, C.A. Woody
2007, Transactions of the American Fisheries Society (136) 452-459
The spawning distribution of sockeye salmon Oncorhynchus nerka was compared between clear and glacially turbid habitats in Lake Clark, Alaska, with the use of radiotelemetry. Tracking of 241 adult sockeye salmon to 27 spawning locations revealed both essential habitats and the relationship between spawn timing and seasonal turbidity cycles. Sixty-six...
Late nineteenth to early twenty-first century behavior of Alaskan glaciers as indicators of changing regional climate
B. F. Molnia
2007, Global and Planetary Change (56) 23-56
Alaska's climate is changing and one of the most significant indications of this change has been the late 19th to early 21st century behavior of Alaskan glaciers. Weather station temperature data document that air temperatures throughout Alaska have been increasing for many decades. Since the mid-20th century, the average change...
Neogene transpressional foreland basin development on the north side of the central alaska range, usibelli group and nenana gravel, tanana basin
K.D. Ridgway, E.E. Thoms, P.W. Layer, M.E. Lesh, J. M. White, S. V. Smith
2007, Special Paper of the Geological Society of America 507-547
Neogene strata of the Tanana basin provide a long-term record of a northwardpropagating, transpressional foreland-basin system related to regional shortening of the central Alaska Range and strike-slip displacement on the Denali fault system. These strata are ???2 km thick and have been deformed and exhumed in thrust faults that form...
Glacier changes in southeast Alaska and northwest British Columbia and contribution to sea level rise
C.F. Larsen, R.J. Motyka, A.A. Arendt, K.A. Echelmeyer, P.E. Geissler
2007, Journal of Geophysical Research F: Earth Surface (112)
The digital elevation model (DEM) from the 2000 Shuttle Radar Topography Mission (SRTM) was differenced from a composite DEM based on air photos dating from 1948 to 1987 to detennine glacier volume changes in southeast Alaska and adjoining Canada. SRTM accuracy was assessed at ??5 in through comparison with airborne...
Pre-, syn-, and postcollisional stratigraphic framework and provenance of upper triassic-upper cretaceous strata in the northwestern talkeetna mountains, alaska
B. A. Hampton, K.D. Ridgway, J.M. O’Neill, G. E. Gehrels, J. Schmidt, R. B. Blodgett
2007, Special Paper of the Geological Society of America 401-438
Mesozoic strata of the northwestern Talkeetna Mountains are located in a regional suture zone between the allochthonous Wrangellia composite terrane and the former Mesozoic continental margin of North America (i.e., the Yukon-Tanana terrane). New geologic mapping, measured stratigraphic sections, and provenance data define a distinct three-part stratigraphy for these strata....
WSR-88D observations of volcanic ash
J. Wood, C. Scott, D. Schneider
2007, Conference Paper, 87th AMS Annual Meeting
Conclusions that may impact operations are summarized below: ??? Current VCPs may not be optimal for the scharacterization of volcanic events. Therefore, the development of a new VCP that combines the enhanced low level elevation density and increased temporal resolution of VCP 12 with the enhanced sensitivity of VCP 31....
Mass dynamics of wintering Pacific Black Brant: Body, adipose tissue, organ, and muscle masses vary with location
D.D. Mason, P.S. Barboza, David H. Ward
2007, Canadian Journal of Zoology (85) 728-736
We compared body size and mass of the whole body, organs, adipose tissue, and muscles of adult Pacific Black Brant (Branta bernicla nigricans (Lawrence, 1846)) collected concurrently in Alaska and Baja California during the fall, winter, and spring of 2002–2003. Head and tarsal lengths of males were similar between sites...
The geophysical character of southern Alaska - Implications for crustal evolution
R. W. Saltus, T. L. Hudson, Frederic H. Wilson
2007, Special Paper of the Geological Society of America (431) 1-20
The southern Alaska continental margin has undergone a long and complicated history of plate convergence, subduction, accretion, and margin-parallel displacements. The crustal character of this continental margin is discernible through combined analysis of aeromagnetic and gravity data with key constraints from previous seismic interpretation. Regional magnetic data are particularly useful...
Detrital zircon geochronology of some neoproterozoic to triassic rocks in interior Alaska
D. C. Bradley, W.C. McClelland, J. L. Wooden, A.B. Till, S. M. Roeske, Marti L. Miller, Susan M. Karl, J.G. Abbott
2007, Special Paper of the Geological Society of America 155-189
No abstract available. ...
Origin of narrow terranes and adjacent major terranes occurring along the Denali fault in the Eastern and Central Alaska Range, Alaska
W. J. Nokleberg, D.H. Richter
2007, Special Paper of the Geological Society of America 129-154
Several narrow terranes occur along the Denali fault in the Eastern and Central Alaska Range in Southern Alaska. These terranes are the Aurora Peak, Cottonwood Creek, Maclaren, Pingston, and Windy terranes, and a terrane of ultramafic and associated rocks. Exterior to the narrow terranes to the...
Metallogeny of the nikolai large igneous province (LIP) in southern alaska and its influence on the mineral potential of the talkeetna mountains
J.M. Schmidt, R.K. Rogers
2007, Special Paper of the Geological Society of America 623-648
Recent geologic mapping has identified areas of extrusive basalts of the Middle to Late Triassic Nikolai Greenstone within the Wrangellia terrane that extend at least 80 km southwest of their previously known extent. Abundant dolerite sills of similar composition intrude Paleozoic and Mesozoic stratigraphy below the Nikolai throughout the central...
Crustal structure of Wrangellia and adjacent terranes inferred from geophysical studies along a transect through the northern Talkeetna Mountains
J.M.G. Glen, J. Schmidt, L. Pellerin, D.K. McPhee, J.M. O’Neill
2007, Special Paper of the Geological Society of America 21-41
Recent investigations of the Talkeetna Mountains in south-central Alaska were undertaken to study the region's framework geophysics and to reinterpret structures and crustal composition. Potential field (gravity and magnetic) and magnetotelluric (MT) data were collected along northwest-trending profiles as part of the U.S. Geological Survey's Talkeetna Mountains transect project. The...
The restricted gemuk group: A triassic to lower cretaceous succession in southwestern Alaska
Marti L. Miller, D. C. Bradley, T. K. Bundtzen, R. B. Blodgett, E.A. Pessagno Jr., R. D. Tucker, A. G. Harris
2007, Special Paper of the Geological Society of America 273-305
New data from an Upper Triassic to Lower Cretaceous deep marine succession-the herein reinstated and restricted Gemuk Group-provide a vital piece of the puzzle for unraveling southwestern Alaska's tectonic history. First defined by Cady et al. in 1955, the Gemuk Group soon became a regional catchall unit that ended up...
Exhumation and continental strike-slip fault systems: Introduction
S. M. Roeske, A.B. Till, D.A. Foster, J.C. Sample
2007, Geological Society of America Special Papers vii-x
Metamorphic rocks adjacent to and within strike-slip faultsystems occur in a wide range of tectonic settings. Detailed studies show that for a number of these locales a significant part of the exhumation occurred during strike-slip fault motion, but the specific processes involved are often cryptic. Although some sites share characteristic...
Upper triassic continental margin strata of the central alaska range: Implications for paleogeographic reconstruction
A.B. Till, A. G. Harris, B. R. Wardlaw, M. Mullen
2007, Special Paper of the Geological Society of America (431) 191-205
Remnants of a Late Triassic continental margin and ocean basin are scattered across central and southern Alaska. Little is known about the fundamental nature of the margin because most remnants have not been studied in detail and a protracted period of terrane accretion and margin-parallel translation has disrupted original...
Crustal structure of the Alaska Range orogen and Denali fault along the Richardson Highway
M. A. Fisher, L. Pellerin, W. J. Nokleberg, N. A. Ratchkovski, J.M.G. Glen
2007, Special Paper of the Geological Society of America 43-53
A suite of geophysical data obtained along the Richardson Highway crosses the eastern Alaska Range and Denali fault and reveals the crustal structure of the orogen. Strong seismic reflections from within the orogen north of the Denali fault dip as steeply as 25° north and extend...
Escape tectonics and the extrusion of Alaska: Past, present, and future
T.F. Redfield, D.W. Scholl, P.G. Fitzgerald, M. E. Beck Jr.
2007, Geology (35) 1039-1042
The North Pacific Rim is a tectonically active plate boundary zone parts of which may be characterized as a laterally moving orogenic stream. Crustal blocks are transported along large-magnitude strike-slip faults in western Canada and central Alaska toward the Aleutian-Bering Sea subduction zones. Throughout much of the Cenozoic, at and...
Geologic map of the Siksikpuk River area, Chandler Lake quadrangle, Alaska
P.R. Peapples, W. K. Wallace, Marwan A. Wartes, R.F. Swenson, C. G. Mull, Julie A. Dumoulin, E. E. Harris, E.S. Finzel, R.R. Reifenstuhl, A.M. Loveland
2007, Report
USGS national surveys and analysis projects: Preliminary compilation of integrated geological datasets for the United States
Suzanne W. Nicholson, Douglas B. Stoeser, Frederic H. Wilson, Connie L. Dicken, Steve Ludington
2007, Conference Paper
The growth in the use of Geographic nformation Systems (GS) has highlighted the need for regional and national digital geologic maps attributed with age and rock type information. Such spatial data can be conveniently used to generate derivative maps for purposes that include mineral-resource assessment, metallogenic studies, tectonic studies, human...
