Skip to main content
Advanced Search

Filters: Tags: Monitoring 5-Physical Science (X)

595 results (14ms)   

View Results as: JSON ATOM CSV
We report on soil development as a function of bedrock type and the presence of loess in two high latitude ecosystems (boreal forest and tundra) and from two regions in Alaska--the Yukon-Tanana Upland (YTU, east-central Alaska) and the Seward Peninsula (SP, far-west coastal Alaska). This approach to the study of "cold soils" is fundamental to the quantification of regional geochemical landscape patterns. Of the five state factors in this study, bedrock and biota (ecosystem; vegetation zone) vary whereas climate (within each area) and topography are controlled. The influence of time is assumed to be controlled, as these soils are thousands of years old (late Quaternary to Holocene). The primary minerals in soils...
This study investigates the runoff process and groundwater behavior in a subarctic watershed called Wolf Creek Research Basin, in Whitehorse, Yukon Territory, Canada. This basin is underlain by discontinuous permafrost that is typical of high latitude watersheds. Goundwater supports the stream flow year round and dominated the hydrology in most of the study period as baseflow. The baseflow was concentrated in dissolved ions. However, the baseflow was diluted during the melt season in May and June of 2012. Multiple chemical and isotopic tracers were used to develop a robust three-component (groundwater, soilwater and precipitation) mixing model for runoff generation. The concentrations of weathering ions decreased...
thumbnail
This study investigates the runoff process and groundwater behavior in a subarctic watershed called Wolf Creek Research Basin, in Whitehorse, Yukon Territory, Canada. This basin is underlain by discontinuous permafrost that is typical of high latitude watersheds. Goundwater supports the stream flow year round and dominated the hydrology in most of the study period as baseflow. The baseflow was concentrated in dissolved ions. However, the baseflow was diluted during the melt season in May and June of 2012. Multiple chemical and isotopic tracers were used to develop a robust three-component (groundwater, soilwater and precipitation) mixing model for runoff generation. The concentrations of weathering ions decreased...
thumbnail
East Forelands and Fire Island have been identified as key sites in Cook Inlet for tidal power extraction and research of potential impacts of MHK devices on the physical environment is an essential element as part of the development and implementation of this technology. Impacts of TidGens and TGUs were simulated using a three dimensional (3D) hydrodynamic model with sediment transport capabilities built using the SNL-EFDC code. Simulated impacts on water age, tidal range and sediment transport appears to be greater at Fire Island than at East Forelands. Simulation of impacts to the bed surface thickness seems to show deposition of fine sediments upstream and downstream of devices at both locations, which corresponds...
thumbnail
Descriptions of the [40] mineral occurrences shown on the accompanying figure follow. See U.S. Geological Survey (1996) [?] for a description of the information content of each field in the records. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska.This and related reports are accessible through the USGS World Wide Web site http://ardf.wr.usgs.gov. Comments or information regarding corrections or missing data, or requests for digital retrievals should be directed to: Frederic Wilson, USGS, 4200 University Dr., Anchorage, AK 99508-4667, e-mail fwilson@usgs.gov, telephone (907) 786-7448.
Decomposition is a critical process in global carbon cycling. During decomposition, leaf and fine root litter may undergo a later, relatively slow phase; past long-term experiments indicate this phase occurs, but whether it is a general phenomenon has not been examined. Data from Long-term Intersite Decomposition Experiment Team, representing 27 sites and nine litter types (for a total of 234 cases) was used to test the frequency of this later, slow phase of decomposition. Litter mass remaining after up to 10 years of decomposition was fit to models that included (dual exponential and asymptotic) or excluded (single exponential) a slow phase. The resultant regression equations were evaluated for goodness of fit...
thumbnail
The complex geology of the Anchorage region contributes to the difficulty in understanding how the North American crust is deforming in response to the oblique collision of North America with the Pacific plate. Previous earthquake studies in the Anchorage Region have shown little to no correlation between earthquakes and known large-scale faults, such as the Castle Mountain Fault system. In this study, I used the Double Difference earthquake relocation technique to identify seismogenic structures in more detail, thus contributing information needed for future seismic hazard assessment of this area. To investigate these potential shallow seismogenic structures, I use a set of events reported by the Alaska Earthquake...
thumbnail
Descriptions of the [8] mineral occurrences shown on the accompanying figure follow. See U.S. Geological Survey (1996) [?] for a description of the information content of each field in the records. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska... This and related reports are accessible through the USGS World Wide Web site http://ardf.wr.usgs.gov. Comments or information regarding corrections or missing data, or requests for digital retrievals should be directed to: Frederic Wilson, USGS, 4200 University Dr., Anchorage, AK 99508-4667, e-mail fwilson@usgs.gov, telephone (907) 786-7448.
map background search result map search result map Alaska Resource Data File; Charley River quadrangle A study of the shallow seismicity in the Anchorage region, south-central, Alaska Late Quaternary megafloods from glacial lake Atna, southcentral Alaska, U.S.A Continuous late Quaternary proxy climate records from loess in Beringia Impacts of marine hydrokinetic devices on hydrodynamics and sediment transport at Fire Island and east Forelands in Cook inlet, Alaska Carbon Stores and Biogeochemical Properties of Soils under Black Spruce Forest, Alaska Studies on ice core records of dicarboxylic acids, ω-oxocarboxylic acids, pyruvic acid, α-dicarbonyls and fatty acids from southern Alaska since 1665 AD: A link to climate change in the Northern Hemisphere Large-Scale Climate Controls of Interior Alaska River Ice Breakup The thickness and internal structure of Fireweed rock glacier, Alaska, U.S.A., as determined by geophysical methods The Geochemistry and Runoff Process in Wolf Creek Research Basin, Whitehorse, Yukon Territory Holocene loess deposition and soil formation as competing processes, Matanuska Valley, southern Alaska Alaska Resource Data File; Kantishna River quadrangle Dissolved Organic Carbon Mobilization and Degradation Patterns in Retrogressive Thaw Slumps of the Peel Plateau, Northwest Territories, Canada Decadal and long-term boreal soil carbon and nitrogen sequestration rates across a variety of ecosystems The Importance of Structural Mapping in Ore Deposits—A New Perspective on the Howard’s Pass Zn-Pb District, Northwest Territories, Canada Studies on ice core records of dicarboxylic acids, ω-oxocarboxylic acids, pyruvic acid, α-dicarbonyls and fatty acids from southern Alaska since 1665 AD: A link to climate change in the Northern Hemisphere Decadal and long-term boreal soil carbon and nitrogen sequestration rates across a variety of ecosystems The Geochemistry and Runoff Process in Wolf Creek Research Basin, Whitehorse, Yukon Territory Impacts of marine hydrokinetic devices on hydrodynamics and sediment transport at Fire Island and east Forelands in Cook inlet, Alaska Holocene loess deposition and soil formation as competing processes, Matanuska Valley, southern Alaska Late Quaternary megafloods from glacial lake Atna, southcentral Alaska, U.S.A Alaska Resource Data File; Charley River quadrangle Alaska Resource Data File; Kantishna River quadrangle Large-Scale Climate Controls of Interior Alaska River Ice Breakup The thickness and internal structure of Fireweed rock glacier, Alaska, U.S.A., as determined by geophysical methods A study of the shallow seismicity in the Anchorage region, south-central, Alaska Dissolved Organic Carbon Mobilization and Degradation Patterns in Retrogressive Thaw Slumps of the Peel Plateau, Northwest Territories, Canada The Importance of Structural Mapping in Ore Deposits—A New Perspective on the Howard’s Pass Zn-Pb District, Northwest Territories, Canada Carbon Stores and Biogeochemical Properties of Soils under Black Spruce Forest, Alaska Continuous late Quaternary proxy climate records from loess in Beringia