Publications
USGS research activities relevant to Alaska have yielded more than 9400 historical publications. This page features some of the most recent newsworthy research findings.
Filter Total Items: 3105
Long-term ecosystem repsonse to the Exxon Valdez oil spill Long-term ecosystem repsonse to the Exxon Valdez oil spill
The ecosystem response to the 1989 spill of oil from the Exxon Valdez into Prince William Sound, Alaska, shows that current practices for assessing ecological risks of oil in the oceans and, by extension, other toxic sources should be changed. Previously, it was assumed that impacts to populations derive almost exclusively from acute mortality. However, in the Alaskan coastal ecosystem...
Authors
C. H. Peterson, S.D. Rice, J.W. Short, Daniel Esler, James L. Bodkin, Brenda E. Ballachey, D.B. Irons
High precision earthquake locations reveal seismogenic structure beneath Mammoth Mountain, California High precision earthquake locations reveal seismogenic structure beneath Mammoth Mountain, California
In 1989, an unusual earthquake swarm occurred beneath Mammoth Mountain that was probably associated with magmatic intrusion. To improve our understanding of this swarm, we relocated Mammoth Mountain earthquakes using a double difference algorithm. Relocated hypocenters reveal that most earthquakes occurred on two structures, a near-vertical plane at 7–9 km depth that has been interpreted...
Authors
Stephanie G. Prejean, Anna Stork, William L. Ellsworth, David Hill, Bruce R. Julian
Controls on intrusion of near-trench magmas of the Sanak-Baranof Belt, Alaska, during Paleogene ridge subduction, and consequences for forearc evolution Controls on intrusion of near-trench magmas of the Sanak-Baranof Belt, Alaska, during Paleogene ridge subduction, and consequences for forearc evolution
A belt of Paleogene near-trench plutons known as the Sanak-Baranof belt intruded the southern Alaska convergent margin. A compilation of isotopic ages of these plutons shows that they range in age from 61 Ma in the west to ca. 50 Ma in the east. This migrating pulse of magmatism along the continental margin is consistent with North Pacific plate reconstructions that suggests the plutons...
Authors
Timothy M. Kusky, Dwight Bradley, D. Thomas Donely, David Rowley, Peter J. Haeussler
Seagrasses of the Pacific Coast of North America Seagrasses of the Pacific Coast of North America
No abstract available.
Authors
David H. Ward, S.E. Ibarra-Obando
Bear-human interactions at Glacier Bay National Park and Preserve: Conflict risk assessment Bear-human interactions at Glacier Bay National Park and Preserve: Conflict risk assessment
Many bear-human conflicts have occurred in Alaska parks and refuges, resulting in area closures, property damage, human injury, and loss of life. Human activity in bear country has also had negative and substantial consequences for bears: disruption of their natural activity patterns, displacement from important habitats, injury, and death. It is unfortunate for both people and bears...
Authors
Tom S. Smith, Terry D. DeBruyn, Tania Lewis, Rusty Yerxa, Steven T. Partridge
Polar bear aerial survey in the eastern Chukchi Sea: A pilot study Polar bear aerial survey in the eastern Chukchi Sea: A pilot study
Alaska has two polar bear populations: the Southern Beaufort Sea population, shared with Canada, and the Chukchi/Bering Seas population, shared with Russia. Currently a reliable population estimate for the Chukchi/Bering Seas population does not exist. Land-based aerial and mark-recapture population surveys may not be possible in the Chukchi Sea because variable ice conditions, the...
Authors
Thomas J. Evans, Anthony S. Fischbach, Scott L. Schliebe, Bryan Manly, Susanne B. Kalxdorff, Geoff S. York
Biogeochemical processes that produce dissolved organic matter from wheat straw Biogeochemical processes that produce dissolved organic matter from wheat straw
The chemical reactions that lead to the formation of dissolved organic matter (DOM) in natural waters are poorly understood. Studies on the formation of DOM generally are complicated because almost all DOM isolates have been derived from mixtures of plant species composed of a wide variety of different types of precursor compounds for DOM formation. This report describes a study of DOM...
Authors
Robert L. Wershaw, David W. Rutherford, Jerry A. Leenheer, Kay R. Kennedy, Larry G. Cox, Donald R. Koci
Variability of the seasonally integrated normalized difference vegetation index across the north slope of Alaska in the 1990s Variability of the seasonally integrated normalized difference vegetation index across the north slope of Alaska in the 1990s
The interannual variability and trend of above-ground photosynthetic activity of Arctic tundra vegetation in the 1990s is examined for the north slope region of Alaska, based on the seasonally integrated normalized difference vegetation index (SINDVI) derived from local area coverage (LAC) National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer...
Authors
D. Stow, Scott Daeschner, A. Hope, David C. Douglas, A. Petersen, Ranga B. Myneni, L. Zhou, W. Oechel
Effect of analytical conditions in wavelength dispersive electron microprobe analysis on the measurement of strontium-to-calcium (Sr/Ca) ratios in otoliths of anadromous salmonids Effect of analytical conditions in wavelength dispersive electron microprobe analysis on the measurement of strontium-to-calcium (Sr/Ca) ratios in otoliths of anadromous salmonids
The use of strontium-to-calcium (Sr/Ca) ratios in otoliths is becoming a standard method to describe life history type and the chronology of migrations between freshwater and seawater habitats in teleosts (e.g. Kalish, 1990; Radtke et al., 1990; Secor, 1992; Rieman et al., 1994; Radtke, 1995; Limburg, 1995; Tzeng et al. 1997; Volk et al., 2000; Zimmerman, 2000; Zimmerman and Reeves, 2000...
Authors
Christian E. Zimmerman, Roger L. Nielsen
Metamorphism within the Chugach accretionary complex on southern Baranof Island, southeastern Alaska Metamorphism within the Chugach accretionary complex on southern Baranof Island, southeastern Alaska
On Baranof Island, southeastern Alaska, we identify four metamorphic events that affect rocks associated with the Chugach accretionary complex. This study focuses on the M1 and M4 metamorphic events. Mesozoic schists, gneisses, and migmatitic gneisses exposed near the Kasnyku pluton on central Baranof Island represent the M1 metamorphic rocks. These rocks underwent amphibolite facies...
Authors
Cathy L. Zumsteg, Glen R. Himmelberg, Susan M. Karl, Peter J. Haeussler
Surgical implantation of transmitters into fish Surgical implantation of transmitters into fish
Although the Animal Welfare Act does not cover poikilotherms, individual institutions and policies and legal requirements other than the Animal Welfare Act (e.g., the US Public Health Service and the Interagency Research Animal Committee's Principles for the Utilization and Care of Vertebrate Animals Used in Testing, Research, and Training) require the review of projects involving fish...
Authors
Daniel M. Mulcahy
Incubation behaviour of Greater Scaup Aythya marila on the Yukon-Kuskokwim Delta, Alaska Incubation behaviour of Greater Scaup Aythya marila on the Yukon-Kuskokwim Delta, Alaska
This study examined the incubation behaviour of Greater Scaup Aythya marila on the Yukon-Kuskokwim Delta, Alaska. The goals of the study were to describe the incubation behaviour of Greater Scaup in terms of incubation constancy, recess frequency and recess length. The use of endogenous reserves by Greater Scaup was examined by determining weight loss over the incubation period. Further
Authors
Paul L. Flint