Filters: Tags: mineralization (X)
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Ar/Ar data are reported from minerals and rocks that were collected as part of a mineral resource investigation of the Tonopah, Divide, and Goldfield districts in Nevada. Data are reported from 92 samples and associated standards from eight separate neutron irradiations in the Denver USGS TRIGA reactor, including separated mineral grains and whole rocks. Data were collected by infrared laser heating of irradiated samples, either incremental heating or fusion, and analysis by multi-collector mass spectrometry. The reported data have been corrected for blanks, radioactive decay, and interfering nucleogenic reactions associated with sample irradiation.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 40Ar/39Ar,
Ar,
Divide district,
Geochemistry,
Goldfield,
This data release includes GIS datasets supporting the Colorado Legacy Mine Lands Watershed Delineation and Scoring tool (WaDeS), a web mapping application available at https://geonarrative.usgs.gov/colmlwades/. Water chemistry data were compiled from the U.S. Geological Survey (USGS) National Water Information System (NWIS), U.S. Environmental Protection Agency (EPA) STORET database, and the USGS Central Colorado Assessment Project (CCAP) (Church and others, 2009). The CCAP study area was used for this application. Samples were summarized at each monitoring station and hardness-dependent chronic and acute toxicity thresholds for aquatic life protections under Colorado Regulation No. 31 (CDPHE, 5 CCR 1002-31) for...
Categories: Data;
Tags: "Mineral Resources"],
"Water Quality",
Arapaho National Forest,
Carson National Forest,
Colorado,
Anthropogenic activity is causing dramatic changes in the nitrogen (N) cycle in many ecosystems. Most research has focused on the increase in N input caused by atmospheric deposition and invasion of N-fixing species, and on their effects on resource availability and species composition. However, in contrast to many ecosystems experiencing large increases in N input, many arid ecosystems are experiencing loss of nutrients due to land-use change. An important component of many arid ecosystems on a worldwide basis is the microbiotic crust, a biological soil crust composed of lichens, cyanobacteria, mosses, and algae. Nitrogen fixation by lichens and cyanobacteria comprising the crust is the primary source of N input...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Canyonlands National Park,
Ecology,
Utah,
cryptogamic crusts,
land-use change,
This USGS Data Release represents tabular data for chemical and physical attributes, rates of deposition, erosion, and mineralization of bank and floodplain sediments and soils from five study sites in the Smith Creek watershed between 2012 and 2015. The data release was produced in compliance with the new 'open data' requirements as a way to make the scientific products associated with USGS research efforts and publications available to the public. The dataset consists of 2 separate items: 1. Smith Creek floodplain soils dataset (tabular data) 2. Smith Creek bank soils dataset (tabular data) These data support the following publication: Gillespie, J.L., Noe, G.B., Hupp, C.R., Gellis, A.C., and Schenk, E.R.,...
Categories: Data;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Chesapeake Bay,
Massanutten Mountain Ridge,
Rockingham County, VA,
Shenandoah County, VA,
Shenandoah Valley,
This dataset contains environmental tracer data from surface water and groundwater samples collected by the U.S. Geological Survey in Redwell Basin, an alpine watershed in the Elk Mountains near the town of Crested Butte, Colorado. The basin is underlain by interbedded shale and sandstone that have been variably hydrothermally altered and silicified by local magmatic intrusions. Samples were collected from 2017 to 2019 from bedrock monitoring wells completed at multiple depths, shallow hand-installed piezometers and mini boreholes, springs, mine adits, and streams. The tracer data include stable isotopes of water (oxygen-18 and deuterium), tritium, dissolved noble gases (He, Ne, Ar, Kr, Xe, and helium-3/helium-4...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Colorado,
Crested Butte,
Elk Mountains,
Environmental Health,
GGGSC,
This data release is a geochemical data set from the reanalysis of 23 rock and 85 sediment samples collected between 1966 and 1970 by the U.S. Geological Survey (USGS) for a series of studies investigating the mineral resources of the Idaho Primitive Area (Cater et al., 1973). The samples are from the upper Middle Fork Salmon River and the South Fork Salmon River, including the tributaries of East Fork of the South Fork and Porphyry Creek. The overall objective of this study is to characterize the regional impact of legacy mining for the Frank Church - River of No Return Wilderness Area. In 1980 the U. S. Congress passed the Central Idaho Wilderness Act which combined the Idaho Primitive Area, the Salmon Rivers...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Automatic Creek,
Beansnapper Creek,
Bear Creek,
Big Chief Creek,
Big Cottonwood Creek,
In the past century, eruptions of Steamboat Geyser in Yellowstone’s Norris Geyser Basin were mainly clustered in three episodes: between 1961 and 1969, between 1982 and 1984, and in a sequence of eruptions that began in 2018 (Reed et al., 2021) and resulted in extensive damage to, and mortality of the surrounding trees. To characterize tree response to geyser activity over time, and the response of geyser activity to climate variability, aerial and ground imagery were analyzed to document changes in tree coverage around the geyser since 1954. Twenty samples of silicified tree remnants were collected from near the geyser vent for radiocarbon (14C) dating to determine if trees grew during periods when the geyser was...
Plant roots and soil microorganisms contain significant quantities of low molecular weight (MW) phosphorylated nucleosides and sugars. Consequently, upon death these can represent a significant input of organic-P to the soil. Some of these organic-P substrates must first be dephosphorylated by phosphatases before being assimilated by the soil microbial community while others can be taken up directly from soil solution. To determine whether sorption or phosphatase activity was limiting the bioavailability of low MW organic-P in soil we compared the microbial uptake and C mineralization of a range of 14C-labeled organic-P substrates [glucose-6-phosphate, adenosine monophosphate (AMP), adenosine diphosphate (ADP) and...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Soil Biology and Biochemistry,
dissolved organic nitrogen,
extracellular enzyme activity,
mineralization,
nutrient cycling,
In the northern semiarid and arid part of Mexico, mesquite (Prosopis juliflora (SW.) DC.), huisache (Acacia farnesiana (L.) Willd.) and catclaw (Mimosa biuncifera Benth.), N2-fixing trees or shrubs, dominate the landscape. It is unknown, however, how much the leaves of those shrubs contribute to dynamics of carbon (C) and nitrogen (N) in soil. We investigated this by adding leaves of each species to soil sampled under the canopy of mesquite, huisache, and catclaw and outside their canopy while monitoring production of carbon dioxide (CO2), and dynamics of inorganic N (ammonium (NH4+) and nitrate (NO3?)) in an aerobic incubation. The (hemi)cellulose and N content of the catclaw leaves was lower and the lignin and...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Journal of Arid Environments,
decomposition of leaves,
emissions of co2,
mineralization,
soil characteristics
The nonnative annual grass Bromus tectorum has successfully replaced native vegetation in many arid and semiarid ecosystems. Initial introductions accompanied grazing and agriculture, making it difficult to separate the effects of invasion from physical disturbance. This study examined N dynamics in two recently invaded, undisturbed vegetation associations (C₃ and C₄). The response of these communities was compared to an invaded/disturbed grassland. The invaded/disturbed communities had higher surface NH₄� input in spring, whereas there were no differences for surface input of NO₃�. Soil inorganic N was dominated by NH₄�, but invaded sites had greater subsurface soil NO₃�. Invaded sites had greater...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Bromus Tectorum,
Ecology,
biological soil crusts,
cheatgrass,
ecosystem nitrogen,
The exploration for porphyry deposits in some parts of Alaska may require unconventional exploration geochemical methods, depending on type of cover. The Taurus deposit and others in the region are mostly concealed by residual soils that in part include ash and loess, and therefore traditional stream sediment samples typically contain subdued geochemical signatures. Indicator mineral studies include collection of stream sediment samples and analysis using automated SEM mineralogical techniques. The presence of select minerals in the stream sediments may indicate mineralization. In addition, the chemistry of specific minerals may be used to distinguish a hydrothermal origin as opposed to others, and include apatite,...
Elaeagnus angustifolia L., a nonnative N2-fixer, has established within riparian corridors of the interior western United States and is now the fourth most frequently occurring woody riparian plant in this region. We examined whether E. angustifolia alters pools and fluxes of soil inorganic N at eight sites dominated by Populus deltoides ssp. wislizeni along the Rio Grande in New Mexico over 2 years. E. angustifolia contributed a small fraction of total leaf fall (<5% across sites) but accounted for a disproportionately high amount of N (19%) that entered the system from P. deltoides and E. angustifolia leaf fall, due to the high N content (>2%) of E. angustifolia senesced leaves. Soil inorganic N concentrations...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Ecosystems,
Elaeagnus angustifolia,
Populus deltoides,
Russian olive,
Springer New York,
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