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Filters: Types: Citation (X) > Tags: {"type":"USGS Scientific Topic Keyword","name":"environmental health"} (X) > partyWithName: U.S. Geological Survey (X) > partyWithName: GS ScienceBase (X)

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The table contains oxide and cation compositions of olivine grains from drill core of the Duluth Complex, Minnesota. The oxides were determined by electron probe microanalysis (EPMA) and are reported in weight percent (wt%). The cations were calculated based on the oxide compositions and are reported in mole percent (mol%). Olivine is a magnesium iron orthosilicate mineral with the formula (Mg2+, Fe2+)2SiO4. Olivine forms a solid solution series with magnesium (Mg) at one end and iron (Fe) at the other. Forsterite (Mg2SiO4) is the magnesium endmember and fayalite (Fe2SiO4) is the iron endmember. Minor elements can substitute into the crystal structure, such as manganese (Mn) and nickel (Ni). To better understand...
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A breach in the White Dam has been proposed to facilitate fish passage. As a Technical Assistance project, the U.S. Geological Survey provided toxicity assessments of sediment samples collected by USEPA personnel. These data describe water-quality conditions in exposure chambers during 42-d sediment exposures using the freshwater amphipod, Hyalella azteca.
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The exposure of white-footed mice (Peromyscus leucopus) to lead and cadmium and the potential associated toxic effects were examined at three sites contaminated with lead in the Southeast Missouri Lead Mining District and at a reference site. Mice from the contaminated sites showed evidence of oxidative stress and red-blood cell δ-aminolevulinic acid dehydratase (ALAD) activity was depressed by an average of 68% at the most contaminated site. However, histological examinations of the liver and kidney, cytologic examination of blood smears and biomarkers of lipid peroxidation and DNA damage failed to show evidence of toxic effects from lead. The biomagnification ratio of cadmium (hepatic concentration/ soil concentration)...
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The table contains oxide and cation compositions of pyroxene grains from drill core in the Duluth Complex. The oxides were determined by electron probe microanalysis (EPMA) and are reported in weight percent (we%). The cations were calculated from the oxide concentrations and are reported in mole percent (mol%). Pyroxene minerals are a group of rock-forming inosilicate minerals with calcium (Ca), iron (Fe), and magnesium (Mg) endmembers. Wollastonite (Wo) is the Ca-endmember with the formula Ca2Si2O6. Ferrosilite (Fs) is the Fe-endmember with the formula Fe2Si2O6, and enstatite (En) is the Mg-endmember with the formula Mg2Si2O6. In order to better understand the chemical compositions of the pyroxenes, the percent...
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The table contains oxide and cation compositions of feldspar grains from drill core of the Duluth Complex. The oxides were determined by electron probe microanalysis (EPMA) and are are reported in weight percent (wt%). The cations were then calculated and are reported in mole percent (mol%). Feldspar grains are a group of rock-forming tectosilicate minerals with potassium (K), sodium (Na), and calcium (Ca) endmembers. Anorthite has a chemical formula CaAlSi3O8; albite has the formula NaAlSi3O8; and orthoclase has the chemical formula KAlSi3O8. To better understand the composition of the measured feldspars, we calculated the anorthite content (An%) as (Ca/(Ca+Na+K)) x 100 and report the values in mol%. Albite (Ab%)...
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Data Release for Report describes surface-water nutrient concentrations from multiple sites on the Conasauga River in northern Georgia in comparison with rivers in adjacent watersheds.
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This table reports major, minor, and trace element compositions of bulk drill core samples from the Duluth Complex, Minnesota. Major elements were measured using wavelength dispersive X-ray fluorescence (XRF) and inductively coupled plasma atomic emission spectrometry (ICP-AES); minor and trace elements were determined using ICP-AES, inductively coupled plasma mass spectrometry (ICP-MS), and hydride generation atomic absorption spectrometry (HGAAS). Total carbon, carbonate carbon, and total sulfur were also analyzed. Total carbon was measured by combustion followed by infrared detection on LECO instrumentation. Carbonate carbon in the bulk rock samples was determined as carbon dioxide by coulometric titration. Total...
    map background search result map search result map Nutrient levels in surface waters of the Conasauga River and other tributaries within the Coosa River Watershed Exposure of Peromyscus leucopus to lead and cadmium in the Southeast Missouri Lead Mining District Toxicity Assessment of Sediments Collected Upstream and Downstream of the White Dam in Clarke County, Georgia Oxide and Cation Compositions of Pyroxene Grains from Drill Core of the Duluth Complex, Minnesota Oxide and Cation Compositions of Olivine Grains from Drill Core in the Duluth Complex, Minnesota Major, Minor, and Trace Element Compositions of Bulk Drill Core Samples from the Duluth Complex, Minnesota Oxide and Cation Compositions of Feldspar Grains from Drill Core of the Duluth Complex, Minnesota Toxicity Assessment of Sediments Collected Upstream and Downstream of the White Dam in Clarke County, Georgia Exposure of Peromyscus leucopus to lead and cadmium in the Southeast Missouri Lead Mining District Nutrient levels in surface waters of the Conasauga River and other tributaries within the Coosa River Watershed Oxide and Cation Compositions of Pyroxene Grains from Drill Core of the Duluth Complex, Minnesota Oxide and Cation Compositions of Olivine Grains from Drill Core in the Duluth Complex, Minnesota Major, Minor, and Trace Element Compositions of Bulk Drill Core Samples from the Duluth Complex, Minnesota Oxide and Cation Compositions of Feldspar Grains from Drill Core of the Duluth Complex, Minnesota