Filters: Tags: Deposition (X)
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Temporal and spatial sources of silica for chert remain poorly constrained. Modern sources to the worlds oceans include silica in rivers > aeolian (dust) deposition > sea floor vents and submarine weathering. However, changes in aridity and dust flux during the Phanerozoic may explain variations in the ocean silica cycle and times and places of chert formation. The chemistry of fine quartz dust (FQD) provides a chemical mechanism for the transformation of FQD to polymorphs of silica in chert; FQD is readily dissolved, then reprecipitated as Opal-A by either biotic or abiotic processes. An unequivocal relation between increases in dust flux and biogenic opal-A in the western Pacific Ocean during the past 200 kyr...
Cultivated lands in the U.S. Midwest have been affected by soil erosion, causing soil organic carbon (SOC) redistribution in the landscape and other environmental and agricultural problems. The importance of SOC redistribution on soil productivity and crop yield, however, is still uncertain. In this study, we used a model framework, which includes the Unit Stream Power-based Erosion Deposition (USPED) and the Tillage Erosion Prediction (TEP) models, to understand the soil and SOC redistribution caused by water and tillage erosion in two agricultural fields in the U.S. Midwest. This model framework was evaluated for different digital elevation model (DEM) spatial resolutions (10-m, 24-m, 30-m, and 56-m) and topographic...
Categories: Publication;
Types: Journal Citation;
Tags: Cs-137,
Deposition,
Erosion,
Midwest United States,
Soil carbon,
This data release consist of the annual sediment depositional volume at five floodplain and five point bar sites on Powder River in southeastern Montana from 1979 through 2017. These 10 sites are a subgroup of a larger group of cross-sections established in 1975 and 1977 to monitor the channel changes along a 90-kilometer reach of Powder River. In addition to the sediment deposition data, characteristic of the annual peak flood are listed. The data are in 1 Excel files containing worksheets (10) corresponding to each channel cross-section .
Categories: Data;
Tags: Geomorphology,
High Plains,
Powder River,
Powder River Basin,
Powder River County,
These topographic/bathymetric digital elevation models (DEMs) were collected and compiled to characterize erosion and deposition in the Colorado River and in an adjacent zone of laterally recirculating flow (eddy) during both average flow conditions and during a controlled flood that occurred in March 2008. The objectives of the study were to measure changes sandbar morphology that occurred during changes in discharge associated with the controlled flood. These data were collected between February 6 and March 31, 2008 in a 1-mile study reach on the Colorado River within Grand Canyon National Park beginning 44.5 miles downstream from Lees Ferry, Arizona. These data were collected by the USGS Grand Canyon Monitoring...
The rates and styles of channel adjustments following an abrupt and voluminous sediment pulse are investigated in the context of site and valley characteristics and time-varying sediment transport regimes. Approximately 10.5 x 106m3 of stored gravel and sand was exposed when Barlin Dam failed during Typhoon WeiPa in 2007. The dam was located on the Dahan River, Taiwan, a system characterized by steep river gradients, typhoon- and monsoon-driven hydrology, high, episodic sediment supply, and highly variable hydraulic conditions. Topography, bulk sediment samples, aerial photos, and simulated hydraulic conditions are analyzed to investigate temporal and spatial patterns in morphology and likely sediment transport...
Categories: Publication;
Types: Citation;
Tags: Barlin Dam,
CALIFORNIA,
CHANNEL RESPONSE,
CREEK,
DEPOSITION,
This project resulted in an extensive mapping of coastal change along the entire coastline of the Western Alaska Landscape Conservation Cooperative (LCC). The work provides important baseline information on the distribution and magnitude of landscape changes over the past 41 years. The extent of change to the coastline and to coastal features, such as spits, barrier islands, estuaries, tidal guts and lagoons, was known to be substantial in some areas along the coast (e.g., portions of the Yukon–Kuskokwim Delta), although the extent of change along the full Bering Sea coast was not well documented. With this analysis, changes can be summarized for different land ownerships or other units to assess the extent of recent...
Categories: Data;
Tags: BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
COASTAL AREAS,
This project resulted in an extensive mapping of coastal change along the entire coastline of the Western Alaska Landscape Conservation Cooperative (LCC). The work provides important baseline information on the distribution and magnitude of landscape changes over the past 41 years. The extent of change to the coastline and to coastal features, such as spits, barrier islands, estuaries, tidal guts and lagoons, was known to be substantial in some areas along the coast (e.g., portions of the Yukon–Kuskokwim Delta), although the extent of change along the full Bering Sea coast was not well documented. With this analysis, changes can be summarized for different land ownerships or other units to assess the extent of recent...
Categories: Data;
Tags: BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
COASTAL AREAS,
This data release comprises nearly three decades of measurements of sandbar topography for monitoring sites along the Colorado River in Grand Canyon National Park and Glen Canyon National Recreation Area. The data were collected to monitor the effects of the operations of Glen Canyon Dam on sandbars, which are also recreational campsites. The data were collected by the US Geological Survey Grand Canyon Monitoring and Research Center in cooperation with Northern Arizona University. Funding for data collection, processing, and reporting has been provided by the Glen Canyon Dam Adaptive Management Program administered by the US Department of the Interior Bureau of Reclamation.
Deposition of suspended dust near eroding source fields can have detrimental effects on vegetation, as well as on soil and water quality. This study was undertaken to quantify dust deposition within 200 m of a source field during wind erosion events. Erosion was measured with BSNE samplers on a small field of Amarillo fine sandy loam at field at Big Spring, TX. Suspension-sized dust discharge averaged 33 � 5 per cent of the total sediment discharge and ranged from 18�0 to 147�4 kg m?1 during eight selected storm events. Within 200 m of the source field boundary, dust collected in deposition samplers placed above a vegetated surface averaged 34 per cent of initial dust discharge. Predicted deposition, according to...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Earth Surface Processes and Landforms,
deposition,
dust,
wind erosion
Changes to the coastline and to coastal features, such as spits, barrier islands, estuaries, tidal guts and lagoons were mapped for over 22,000 km of coastline along the Bering Sea and Gulf of Alaska coasts in western Alaska. Changes to rivers and lakes near the coast were also captured. The analysis was based on time-series analysis of Landsat imagery, 1972–2013. An annual imeseries of suitable Landsat imagery was compiled and analyzed for changes in near-infrared reflectance to identify areas that transitioned from land to water, or vice-versa, over the study period. The timing of changes was also identified. Thousands of coastal changes over the 42-year study period exceeded the 60-m pixel resolution of the Multispectral...
Categories: Data;
Tags: BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
COASTAL AREAS,
Interactions between geomorphic processes at multiple scales shape the distributions of habitats, species, and life stages that a river can support. Understanding these hierarchical processes may be helpful for proactive monitoring and restoration of native Western Brook Lamprey (Lampetra richardsoni) and Pacific Lamprey (Entosphenus tridentatus) in Pacific Northwest rivers. The processes creating thick, fine-grained sediment deposits that lamprey larvae rely on as rearing habitat were assessed in part through field sampling in the Umpqua River basin, southwestern Oregon, USA. Local factors, such as substrate, boulders, wood, and water, that control sediment erosion and deposition, affecting larval lamprey habitat,...
Interactions between geomorphic processes at multiple scales shape the distributions of habitats, species, and life stages that a river can support. Understanding these hierarchical processes may be helpful for proactive monitoring and restoration of native Western Brook Lamprey (Lampetra richardsoni) and Pacific Lamprey (Entosphenus tridentatus) in Pacific Northwest rivers. The processes creating thick, fine-grained sediment deposits that lamprey larvae rely on as rearing habitat were assessed in part through field sampling in the Umpqua River basin, southwestern Oregon, USA. Local factors, such as substrate, boulders, wood, and water, that control sediment erosion and deposition, affecting larval lamprey habitat,...
Categories: Data;
Tags: Cascades Range,
Douglas County,
Klamath Mountains,
Little Wolf Creek,
Oregon Coast Range,
Land use land cover (LULC) plays an important role in influencing the spatial intensity of water erosion which is the primary governor of horizontal translocation of soil organic carbon (SOC). The fate of redistributed SOC through erosion remains debatable and the mineralization rate of exposed SOC protected in soil aggregates is the major focus of this argument. Cohesive spatially explicit modeling of SOC and erosion can potentially reduce some of the controversy. To this end we simulated erosion/deposition, and photosynthetic (in situ) flux of SOC in a small watershed of ~ 28.42 ha, located in the Big Creek basin of southern Illinois. The main objectives of this research were: (a) to study erosion and deposition...
Categories: Publication;
Types: Citation;
Tags: CENTURY,
Data Visualization & Tools,
Deposition,
Erosion,
GeoWEPP,
This is a multi-disciplinary community of scientists who study the effects of wildfire disturbance on the built and natural environment. The mission is to understand natural processes such as infiltration, rainfall-runoff, erosion, sediment and chemical transport, and water quality effects. The focus is on obtaining field-based measurements that can be used to improve or develop models for use by emergency, land and water supply managers as tools for decision making.
The project will complete an extensive mapping of coastal change along the entire coastline of the Western Alaska Landscape Conservation Cooperative (LCC). The work will provide important baseline information on the distribution and magnitude of landscape changes over the past 41 years. The extent of change to the coastline and to coastal features, such as spits, barrier islands, estuaries, tidal guts and lagoons, is known to be substantial in some areas along the coast (e.g., portions of the Yukon–Kuskokwim Delta), although the extent of change along the full Bering Sea coast is not well documented. With this analysis, changes can be summarized for different land ownerships or other units to assess the extent of...
Categories: Data,
Project;
Tags: BARRIER ISLANDS,
BARRIER ISLANDS,
COASTAL LANDFORMS/PROCESSES,
COASTAL LANDFORMS/PROCESSES,
DEGRADATION,
This project resulted in an extensive mapping of coastal change along the entire coastline of the Western Alaska Landscape Conservation Cooperative (LCC). The work provides important baseline information on the distribution and magnitude of landscape changes over the past 41 years. The extent of change to the coastline and to coastal features, such as spits, barrier islands, estuaries, tidal guts and lagoons, was known to be substantial in some areas along the coast (e.g., portions of the Yukon–Kuskokwim Delta), although the extent of change along the full Bering Sea coast was not well documented. With this analysis, changes can be summarized for different land ownerships or other units to assess the extent of recent...
Categories: Data;
Tags: BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
COASTAL AREAS,
This project resulted in an extensive mapping of coastal change along the entire coastline of the Western Alaska Landscape Conservation Cooperative (LCC). The work provides important baseline information on the distribution and magnitude of landscape changes over the past 41 years. The extent of change to the coastline and to coastal features, such as spits, barrier islands, estuaries, tidal guts and lagoons, was known to be substantial in some areas along the coast (e.g., portions of the Yukon–Kuskokwim Delta), although the extent of change along the full Bering Sea coast was not well documented. With this analysis, changes can be summarized for different land ownerships or other units to assess the extent of recent...
Categories: Data;
Tags: BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
COASTAL AREAS,
The consequence of the 1996 Buffalo Creek wildfire disturbance and a subsequent high-intensity summer convective rain storm (~100 mm h-1) was the deposition of a sediment superslug in the Spring Creek basin (26.8 km2) of the Front Range Mountains in Colorado. Changes in the superslug near the confluence of Spring Creek with the South Platte River were monitored by cross-section surveys at 18 nearly equally-spaced cross sections along a 1500 m study reach for 18 years (1996-2014) to understand the evolution and internal stratigraphy of this type of disturbance in response to different geomorphic processes. These data consist of 18 Excel files (one for each cross section) containing worksheets corresponding to each...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Colorado,
Front Range,
Geomorphology,
Jefferson County,
Spring Creek,
This project resulted in an extensive mapping of coastal change along the entire coastline of the Western Alaska Landscape Conservation Cooperative (LCC). The work provides important baseline information on the distribution and magnitude of landscape changes over the past 41 years. The extent of change to the coastline and to coastal features, such as spits, barrier islands, estuaries, tidal guts and lagoons, was known to be substantial in some areas along the coast (e.g., portions of the Yukon–Kuskokwim Delta), although the extent of change along the full Bering Sea coast was not well documented. With this analysis, changes can be summarized for different land ownerships or other units to assess the extent of recent...
Categories: Data;
Tags: BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
COASTAL AREAS,
This project resulted in an extensive mapping of coastal change along the entire coastline of the Western Alaska Landscape Conservation Cooperative (LCC). The work provides important baseline information on the distribution and magnitude of landscape changes over the past 41 years. The extent of change to the coastline and to coastal features, such as spits, barrier islands, estuaries, tidal guts and lagoons, was known to be substantial in some areas along the coast (e.g., portions of the Yukon–Kuskokwim Delta), although the extent of change along the full Bering Sea coast was not well documented. With this analysis, changes can be summarized for different land ownerships or other units to assess the extent of recent...
Categories: Data;
Tags: BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
BARRIER ISLANDS,
COASTAL AREAS,
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