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These data can be used to replicate the application of MWBMglacier as described in two journal articles: 1) Enhancement of a parsimonious water balance model to simulate surface hydrology in a glacierized watershed (in review), and 2) Hydrologic regime changes in a high-latitude glacierized watershed under future climate conditions (doi:10.3390/w10020128). These simulations provide results from historical and 12 future general circulation model scenarios for the period 1949-2099 to determine the potential effects of climate change on the hydrology and water quality of a snow-dominated mountainous environment. In addition to the inputs and outputs, this Data Release includes summaries of the input and output data...
The lateral blast, debris avalanche, and lahars of the May 18th, 1980, eruption of Mount St. Helens, Washington, dramatically altered the surrounding landscape. Lava domes were extruded during the subsequent eruptive periods of 1980-1986 and 2004-2008. During 2017, U.S. Forest Service contracted the acquisitions of airborne lidar surveys of Mount St. Helens and upper North Fork Toutle River basin, part of a larger 2017-2018 survey of the Gifford Pinchot National Forest. The U.S. Geological Survey combined and reprojected 81 raster datasets, provided by the U.S. Forest Service in October 2018, into a single digital elevation model (DEM) of the ground surface, including beneath forest cover (that is, 'bare earth')....
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This report summarizes the geochronologic results from boulders deposited on glacial moraines in the southern Sawatch and Sangre de Cristo Mountains of south-central Colorado. Within this report are detailed the methodology used to collect samples of whole rock, determine the concentrations of cosmogenic beryllium 10 in purified quartz isolated from those samples, and use those nuclide concentrations to calculate surface exposure ages. This report should be used as supplementary material for any publication(s) that uses the nuclide concentrations and/or ages reported herein. This version supersedes all previous age estimates and reports.
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This digital map shows the geographic extent of rock stratigraphic units (formations) as compiled by Colton in 1976 under the Front Range Urban Corridor Geology Program. Colton used his own geologic mapping and previously published geologic maps to compile one map having a single classification of geologic units. The resulting published color paper map (USGS Map I-855-G, Colton, 1978) was intended for land-use planning and to depict the regional geology. In 1997-1999, another USGS project designed to address urban growth issues was undertaken. This project, the USGS Front Range Infrastructure Resources Project, undertook to digitize Colton's map at 1:100,000 scale, making it useable in Geographical Information Systems...
Tags: Boulder, Boulder County, Boulder Creek granodiorite, Colorado, Colorado Front Range, All tags...
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The Glacial Environments and Surficial Sediments geodatabase (GESS) data includes a polygon file with multiple attributes which describe the lithology, geomorphology, and related depositional environment of Quaternary-age surfical sediments in the glaciated conterminous United States. These attributes include: the map unit (GESS_MU), a geomorphic modifier (GESS_Modifier), a sediment stratification indicator (SedStrat), and a a sediment texture classification (Texture6). Possible GESS_MU values include: alluvial sediment, colluvial sediment, eolian sediment, lacustrine sediment, marine sediment, organic sediment, outwash, ice-contact deposits, island, residual soils, soliflucted sediment, till, bedrock, fill, and...
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At times during the past two million years, glaciers formed in the mountainous part of the Platte River drainage basin. These glaceriers were predominantly valley glaciers, also commonly referred to a s mountain or alpine glaciers. by definition, valley glaciers flow through pre-existing valleys and are bounded by exposed bedrock. the deep valleys and canyons of the map area already existed at the beginning of the Ice Age as a result of regional uplift and subsequent erosion that occured from late Oligocene through Pliocene time. the largest valley glacier in the map area was 45 km long and as much as 600 m thick. During times when Pleistocene glaciers reached their maximum extent, about 10 percent of the mountainous...
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Since the late 1950s, the USGS has maintained a long-term glacier mass-balance program at three North American glaciers. Measurements began on South Cascade Glacier, WA in 1958, expanding to Gulkana and Wolverine glaciers, AK in 1966, and later Sperry Glacier, MT in 2005. The Juneau Icefield Research Program has measured surface mass balance on Lemon Creek and Taku Glacier since the mid-1940s, with USGS providing complimentary seasonal measurements of Lemon Creek beginning in 2014 (JIRP; Pelto and others, 2013). Direct field measurements of point glaciological data are combined with weather and geodetic data to estimate the seasonal and annual mass balance at each glacier in both a conventional and reference surface...
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The lateral blast, debris avalanche, and lahars of the May 18th, 1980, eruption of Mount St. Helens, Washington, dramatically altered the surrounding landscape. Lava domes were extruded during the subsequent eruptive periods of 1980-1986 and 2004-2008. During 2022, U.S. Army Corps of Engineers contracted the acquisitions of airborne lidar surveys of Mount St. Helens crater and two primary drainages–upper North Fork Toutle River and South Fork Toutle River with GeoTerra, Inc. The U.S. Geological Survey generated a terrain dataset from the classified point cloud with supplied breaklines and modified lake hydro-flattening, then exported a single digital elevation model (DEM) of the ground surface (that is, 'bare earth'),...
We have developed a physically based, distributed surface energy balance model to simulate glacier mass balance under meteorological and climatological forcing. Here we apply the model to estimate summer ablation on South Cascade Glacier, Washington, for the 2004 and 2005 mass balance seasons. To arrive at optimal mass balance simulations, we investigate and quantify model uncertainty associated with selecting from a range of physical parameter values that are not commonly measured in glaciological mass balance field studies. We optimize the performance of the model by varying values for atmospheric transmissivity, the albedo of surrounding topography, precipitation-elevation lapse rate, surface roughness for turbulent...
Categories: Publication; Types: Citation; Tags: Climate, glaciology, modeling
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From 2013 to 2018, the U.S. Geological Survey, in cooperation with the Town of Enfield and the Tompkins County Planning Department, studied the unconsolidated aquifers in the Enfield Creek Valley in the town of Enfield, Tompkins County, New York. The objective of this study was to characterize the geohydrology and water quality of the unconsolidated aquifers in the Enfield Creek valley and produce a summary report of the findings. The spatial extent and geohydrologic framework of these unconsolidated aquifers were delineated using existing data, including soils maps, well records, geologic logs, topographic data, and published reports. An interactive ArcGIS Online web map of the geospatial datasets is available...
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In coastal subarctic environments such as the fjords of Southeast Alaska, tidewater glaciers can control local hydrology, climatic patterns, ecology, and geologic hazards like landslides and consequent tsunami waves. Documenting and studying glacial retreat in fjords can help scientists understand the dynamic systems that are intrinsically tied to glacial ice processes and forecast changes in these systems. Detailed inventories of glacial retreat have been produced using satellite images and other remote data spanning back to the mid-1900s. However, compiling data on ice positions from before the availability of remotely sensed data requires the existence of historical observations and surveys; oral or written accounts;...
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Glacial retreat and mountain-permafrost degradation resulting from rising global temperatures have the potential to impact the frequency and magnitude of landslides in glaciated environments. In the Saint Elias Mountains of southeast Alaska, the presence of weak sedimentary and metamorphic rocks and active uplift resulting from the collision of the Yakutat and North American tectonic plates create landslide-prone conditions (Winkler et al., 2000). We used Landsat imagery to create an inventory of large (>0.1 square km) rock avalanches that occurred along the south flank of the Saint Elias Mountains between 1984 and 2019 as a baseline for present and future changes in landslide magnitude and frequency. This data...
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The Hydrogeologic Terranes dataset includes separate polygon and line feature classes. The polygon feature class divides the glaciated United States into seventeen distinct terranes using a geologically based approach. Each terrane contains Quaternary sediment that is derived from a common depositional history and can be characterized by texture and thickness. Delineation of hydrogeologic terranes was based on an interpretation of existing geologic mapping of surficial and Quaternary deposits, and thickness of unconsolidated material. Overall thickness of Quaternary sediment was used to qualitatively rank the generalized complexity of geologic framework in each terrane: "lower" complexity (assigned a terrane code...
Ground-based transient electromagnetic (TEM) data were acquired by the U.S. Geological Survey (USGS) in selected locations near Manistee National Forest, Michigan, to define the resistivity structure of the subsurface. Data were acquired using the ABEM WalkTEM system (Guideline Geo Ab, Sundbyberg, Sweden). TEM data were processed and numerically inverted to derive one-dimensional resistivity structure using SPIA (Aarhus Geosoftware, Aarhus, Denmark). This release includes raw and processed TEM data and resistivity models for each data location using the following structure: MIT_TEM_2020.zip ├── Data │ ├── MIT_USF │ │ ├── USF_format_description.pdf - manual describing the USF file format │ │ ├── MIT_SoundingID-USF_lookup.csv...
map background search result map search result map Hydrogeologic Terranes for Glaciated Conterminous United States Glacial Environments and Surficial Sediments (GESS) Geodatabase for the Glaciated, Conterminous United States Supporting data for two MWBMglacier applications to the Copper River basin in Alaska High-resolution digital elevation model of Mount St. Helens and upper North Fork Toutle River basin, based on airborne lidar surveys of July-September, 2017 Geospatial Datasets for the Geohydrology and Water Quality of the Unconsolidated Aquifers in the Enfield Creek Valley, Town of Enfield, Tompkins County, New York Inventory data of rock avalanches in the Saint Elias Mountains of southeast Alaska, derived from Landsat imagery (1984-2019) Hydrogeologic section lines in valleys of the Oneonta area, New York Inferred valley ice tongue positions in the Oneonta area, Otsego and Delaware Counties, New York Valley-fill aquifer extent in the Oneonta area, Otsego and Delaware Counties, New York Unconfined and semi-confined aquifer areas in the Oneonta area, Otsego and Delaware Counties, New York Eskerform features in the Oneonta area, Otsego and Delaware Counties, New York Well data from the Oneonta area, Otsego and Delaware Counties, New York Ground-based time-domain electromagnetic data and resistivity models near Manistee National Forest, Michigan, 2020 Data release for cosmogenic beryllium-10 exposure ages of boulders deposited on moraines in the southern Sawatch and Sangre de Cristo Mountains, southern Colorado Data Release - Pleistocene Glaciation in the Upper Platte River Drainage Basin, Colorado Digital database of the previously published geologic map of the Boulder-Fort Collins-Greeley area, Colorado Glacier-Wide Mass Balance and Compiled Data Inputs Digital compilation of historical ice terminus positions of tidewater glaciers in Glacier Bay National Park and Preserve, Alaska Geospatial Datasets for the Geohydrology and Water Quality of the Unconsolidated Aquifers in the Enfield Creek Valley, Town of Enfield, Tompkins County, New York High-resolution digital elevation model of Mount St. Helens and upper North Fork Toutle River basin, based on airborne lidar surveys of July-September, 2017 Eskerform features in the Oneonta area, Otsego and Delaware Counties, New York Well data from the Oneonta area, Otsego and Delaware Counties, New York Ground-based time-domain electromagnetic data and resistivity models near Manistee National Forest, Michigan, 2020 Digital database of the previously published geologic map of the Boulder-Fort Collins-Greeley area, Colorado Data release for cosmogenic beryllium-10 exposure ages of boulders deposited on moraines in the southern Sawatch and Sangre de Cristo Mountains, southern Colorado Inventory data of rock avalanches in the Saint Elias Mountains of southeast Alaska, derived from Landsat imagery (1984-2019) Data Release - Pleistocene Glaciation in the Upper Platte River Drainage Basin, Colorado Digital compilation of historical ice terminus positions of tidewater glaciers in Glacier Bay National Park and Preserve, Alaska Supporting data for two MWBMglacier applications to the Copper River basin in Alaska Glacier-Wide Mass Balance and Compiled Data Inputs Hydrogeologic Terranes for Glaciated Conterminous United States Glacial Environments and Surficial Sediments (GESS) Geodatabase for the Glaciated, Conterminous United States