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Samples of the crater lake water were filtered in the field with a 0.45 micron filter. Subsequently, additional precipitates formed in the solute-rich samples (secondary precipitates) which were subsequently filtered in the lab with a 0.45 micron filter. Resulting residues were analyzed both in situ on the filter and after scraping. Samples were sputter coated with 10 nm Au, then imaged in a Tescan VEGA3 scanning electron microscope (SEM) equipped with an Oxford 150 mm2 X-MaxN large area energy dispersive spectrometer at the U.S. Geological Survey, Menlo Park, CA. Elemental backscatter (BSE) images were collected with an accelerating voltage (HV) of 30 kV and a working distance (WD) of ~15 mm. Magnification is indicated...
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Samples of the crater lake water were filtered in the field with a 0.45 micron filter. Subsequently, additional precipitates formed in the solute-rich samples (secondary precipitates) which were subsequently filtered in the lab with a 0.45 micron filter. The mineralogy of secondary precipitates for samples HM19-01 and HM20-01A,B,C that were collected on 10/26/2019 and on 1/17/2020, respectively was determined by X-ray diffraction (XRD). Analysis was carried out at the British Natural History Museum with a Enraf-Nonius PDS120 diffractometer equipped with a primary Germanium (111) monochromator and an INEL 120° curved position sensitive detector (PSD). Data were collected from 7-120° 2θ using Co Kalpha1 radiation...
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Samples for water chemistry analysis were filtered to 0.45 µm upon collection. Since the solute-rich samples continued to form precipitates, samples were filtered again immediately prior to analysis if needed. All samples were very rich in solutes and were analyzed at multiple dilutions (1:100 to 1:1000) to match instrument measurement ranges for various analytes. Water chemistry analyses were performed at the U.S. Geological Survey laboratories in Menlo Park, California. The concentrations of fluoride (F-), chloride (Cl-), sulfate (SO42-), and bromide (Br-) in samples were determined by ion chromatography with a Dionex ICS-2000, using a 250 mm Dionex IonPac AS18 column. The concentrations of major cations...
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Following the 2018 eruption of Kīlauea Volcano (Neal et al, 2019) and the subsequent collapse of the Halema’uma’u crater, groundwater gradually seeped into the newly-deepened crater (Nadeau and others, 2020). Water was first observed in the crater on 7/26/2019, and the water level increased over time until 12/20/2020, when the crater again filled with lava, vaporizing the lake. In the intervening time, three sets of water samples were collected by unoccupied aircraft systems (UAS) and analyzed for water chemistry, water isotopes, and sulfur isotopes. The solids filtered from the collected water samples were analyzed by XRD and SEM, as well as digested and analyzed for their chemical composition. Additionally, two...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Kilauea, Halema'uma'u, Hawaii,
USGS Science Data Catalog (SDC),
biota,
volcanic lake, geochemistry, water chemistry, water isotopes, sulfur isotopes
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Aliquots of collected water samples were prepared for isotopic analysis at the USGS laboratories in Menlo Park, CA by precipitating dissolved sulfate as barium sulfate, using the methods of Carmody and others (1997). Sulfur isotopes were analyzed at the USGS laboratories in Reston, Virginia. For sulfur isotope ratio measurements, dissolved sulfate is converted to BaSO4, which is analyzed by conversion to sulfur dioxide with an elemental analyzer and subsequent analysis with a continuous flow isotope ratio mass spectrometer (Brenna, 1997). Samples are analyzed simultaneously with BaSO4 isotopic reference materials. No correction for oxygen isotopic composition is made to the reported sulfur isotope data. For...
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