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S. J. Sutley

Publications and source records attributed to S. J. Sutley.

At least 19 recordsLinked to original sources
USGS2009

Mapping potentialy asbestos-bearing rocks using imaging spectroscopy

Rock and soil that may contain naturally occurring asbestos (NOA), a known human carcinogen, were mapped in the Sierra Nevada, California, using the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) to determine if these materials could be uniquely identified with spectroscopy. Such information can be used to prepare or refine maps of areas that may contain minerals that can be asbestiform, such as serpentine and tremolite-actinolite, which were the focus of this study. Although thick vegetation can conceal underlying rock and soil, use of linear-mixture spectra calculated from spectra of dry grass and serpentine allowed detection of serpentine in some parts of the study area with up to ~80% dry-grass cover. Chaparral vegetation, which was dominantly, but not exclusively, found in areas underlain by serpentinized ultramafic rocks, was also mapped. Overall, field checking at 201 sites indicated highly accurate identification by AVIRIS of mineral (94%) and vegetation (89%) categories. Practical applications of AVIRIS to mapping areas that may contain NOA include locating roads that are surfaced with serpentine aggregate, identifying sites that may require enhanced dust control or other safety measures, and filling gaps in geologic mapping where field access is limited.

Geology↗
USGS2008

Chromium, chromium isotopes and selected trace elements, western Mojave Desert, USA

Chromium(VI) concentrations in excess of the California Maximum Contaminant Level (MCL) of 50 μg/L occur naturally in alkaline, oxic ground-water in alluvial aquifers in the western Mojave Desert, southern California. The highest concentrations were measured in aquifers eroded from mafic rock, but Cr(VI) as high as 27 μg/L was measured in aquifers eroded from granitic rock. Chromium(VI) concentrations did not exceed 5 μg/L at pH < 7.5 regardless of geology. δ 53 Cr values in native ground-water ranged from 0.7 to 5.1‰ and values were fractionated relative to the average δ 53 Cr composition of 0‰ in the earth’s crust. Positive δ 53 Cr values of 1.2 and 2.3‰ were measured in ground-water recharge areas having low Cr concentrations, consistent with the addition of Cr(VI) that was fractionated on mineral surfaces prior to entering solution. δ 53 Cr values, although variable, did not consistently increase or decrease with increasing Cr concentrations as ground-water flowed down gradient through more oxic portions of the aquifer. However, increasing δ 53 Cr values were observed as dissolved O 2 concentrations decreased, and Cr(VI) was reduced to Cr(III), and subsequently removed from solution. As a result, the highest δ 53 Cr values were measured in water from deep wells, and wells in discharge areas near dry lakes at the downgradient end of long flow paths through alluvial aquifers. δ 53 Cr values at an industrial site overlying mafic alluvium having high natural background Cr(VI) concentrations ranged from −0.1 to 3.2‰. Near zero δ 53 Cr values at the site were the result of anthropogenic Cr. However, mixing with native ground-water and fractionation of Cr within the plume increased δ 53 Cr values at the site. Although δ 53 Cr was not necessarily diagnostic of anthropogenic Cr, it was possible to identify the extent of anthropogenic Cr at the site on the basis of the δ 53 Cr values in conjunction with major-ion data, and the δ 18 O and δD composition of water from wells.

Applied Geochemistry↗
USGS2006

Mineralogy and Morphology of Amphiboles Observed in Soils and Rocks in El Dorado Hills, California

From the Executive Summary: At the request of the U.S. Environmental Protection Agency (USEPA), the U.S. Geological Survey (USGS) has conducted an independent study of amphiboles in rocks and soils in the El Dorado Hills, California, area. The purpose of this study is to investigate specific issues regarding the presence of 'naturally occurring asbestos' raised by an USEPA activity-based sampling study and subsequent criticisms of that study outlined in a review prepared by The R.J. Lee Group (RJLG).

Open-File Report↗
USGS2004

Using the geologic setting of talc deposits as an indicator of amphibole asbestos content

This study examined commercial talc deposits in the U.S. and their amphibole-asbestos content. The study found that the talc-forming environment directly influenced the amphibole and amphibole-asbestos content of the talc deposit. Large talc districts in the U.S. have mined hydrothermal talcs that replaced dolostone. Hydrothermal talcs, created by siliceous fluids heated by magmas at depth, consistently lack amphiboles as accessory minerals. In contrast, mineable talc deposits that formed by contact or regional metamorphism consistently contain amphiboles, locally as asbestiform varieties. Examples of contact metamorphic deposits occur in Death Valley, California; these talc-tremolite deposits contain accessory amphibole-asbestos. Talc bodies formed by regional metamorphism always contain amphiboles, which display a variety of compositions and habits, including asbestiform. Some industrial mineral deposits are under scrutiny as potential sources of accessory asbestos minerals. Recognizing consistent relations between the talc-forming environment and amphibole-asbestos content may be used in prioritizing remediation or monitoring of abandoned and active talc mines.

Environmental Geology↗
USGS2003

Questa baseline and pre-mining ground water investigation: 11. Geochemistry of composited material from alteration scars and mine-waste piles

Composited, surficial material was collected from alteration scars, a less intensely altered site, and mine-waste piles. All samples were analyzed for forty elements by inductively coupled plasma-atomic emission spectrometry, total sulfur and quantitative X-ray diffraction. This work was performed in cooperation with the New Mexico Environment Department.

New Mexico↗
USGS2003

The composition and morphology of amphiboles from the Rainy Creek complex, near Libby, Montana

Thirty samples of amphibole-rich rock from the largest mined vermiculite deposit in the world in the Rainy Creek alkaline-ultramafic complex near Libby, Montana, were collected and analyzed. The amphibole-rich rock is the suspected cause of an abnormally high number of asbestos-related diseases reported in the residents of Libby, and in former mine and mill workers. The amphibole-rich samples were analyzed to determine composition and morphology of both fibrous and non-fibrous amphiboles. Sampling was carried out across the accessible portions of the deposit to obtain as complete a representation of the distribution of amphibole types as possible. The range of amphibole compositions, determined from electron probe microanalysis and X-ray diffraction analysis, indicates the presence of winchite, richterite, tremolite, and magnesioriebeckite. The amphiboles from Vermiculite Mountain show nearly complete solid solution between these end-member compositions. Magnesio-arfvedsonite and edenite may also be present in low abundance. An evaluation of the textural characteristics of the amphiboles shows the material to include a complete range of morphologies from prismatic crystals to asbestiform fibers. The morphology of the majority of the material is intermediate between these two varieties. All of the amphiboles, with the possible exception of magnesioriebeckite, can occur in fibrous or asbestiform habit. The Vermiculite Mountain amphiboles, even when originally present as massive material, can produce abundant, extremely fine fibers by gentle abrasion or crushing.

American Mineralogist↗
USGS2000

Analytical data for reconnaissance geochemical samples from mine dumps, stream sediments and waters at the Thompson Creek Tungsten Mine, Custer County, Idaho

The Thompson Creek mine is an inactive and abandoned tungsten mine located along Thompson Creek about 10.5 miles (17 km) northwest of Clayton, Idaho (see location map in file LOCATION.PDF). The mine consisted initially of open pit mining of outcrops and later of underground workings accessed by a single adit. The mine was worked through 1955 and waste piles presently reside in the flood plain above the east bank of Thompson Creek. A view of the collapsed adit is provided in the TIFF (Tagged-Image File Format) file ADIT.TIF (all photographs taken on 08/13/99). A south-facing view of the mine waste dumps is provided in the TIFF file SOUTH.TIF and a north-facing view is provided in NORTH.TIF.

Idaho↗
USGS1999

Using imaging spectroscopy to map acidic mine waste

The process of pyrite oxidation at the surface of mine waste may produce acidic water that is gradually neutralized as it drains away from the waste, depositing different Fe-bearing secondary minerals in roughly concentric zones that emanate from mine-waste piles. These Fe-bearing minerals are indicators of the geochemical conditions under which they form. Airborne and orbital imaging spectrometers can be used to map these mineral zones because each of these Fe-bearing secondary minerals is spectrally unique. In this way, imaging spectroscopy can be used to rapidly screen entire mining districts for potential sources of surface acid drainage and to detect acid producing minerals in mine waste or unmined rock outcrops. Spectral data from the AVIRIS instrument were used to evaluate mine waste at the California Gulch Superfund Site near Leadville, CO. Laboratory leach tests of surface samples show that leachate pH is most acidic and metals most mobile in samples from the inner jarosite zone and that leachate pH is near-neutral and metals least mobile in samples from the outer goethite zone.

Environmental Science & Technology↗
USGS1999

Simmonsite, Na2LiAlF6, a new mineral from the Zapot amazonite-topazzinnwaldite pegmatite, Hawthorne, Nevada, U.S.A

Simmonsite, Na2LiAlF6, a new mineral of pegmatitic-hydrothermal origin, occurs in a late-stage breccia pipe structure that cuts the Zapot amazonite-topaz-zinnvvaldite pegmatite located in the Gillis Range, Mineral Co., Nevada, U.S.A. The mineral is intimately intergrown with cryolite, cryolithionite and trace elpasolite. A secondary assemblage of other alumino-fluoride minerals and a second generation of cryolithionite has formed from the primary assemblage. The mineral is monoclinic, P21 or P21/m, a = 7.5006(6) A??, b = 7.474(1) A??, c = 7.503(1) A??, ??= 90.847(9) ??, V=420.6(1) A??3, Z = 4. The four strongest diffraction maxima [d(A??), likl, I/I100] are (4.33, 111 and 111, 100); (1.877, 400 and 004, 90); (2.25, 13T, 113, 131 and 311, 70); and (2.65, 220, 202, 022, 60). Simmonsite is pale buff cream with white streak, somewhat greasy, translucent to transparent, Mohs hardness of 2.5-3, no distinct cleavage, subconchoidal fracture, no parting, not extremely brittle, Dm is 3.05(2) g/cm3, and Dc is 3.06(1) g/cm3. The mineral is biaxial, very nearly Isotropie, N is 1.359(1) for ?? = 589 nm, and birefringence is 0.0009. Electron microprobe analyses gave (wt%) Na = 23.4, Al = 13.9, F = 58.6, Li = 3.56 (calculated), with a total of 99.46. The empirical formula (based on 6 F atoms) is Na1.98Li1.00 ooAl|ooF6. The crystal structure was not solved, presumably because of unit-cell scale twinning, but similarities to the perovskite-type structure exist. The mineral is named for William B. Simmons, Professor of Mineralogy and Petrology, University of New Orleans, New Orleans.

American Mineralogist↗
USGS1995

Hydrologic data for the Fristoe Unit of the Mark Twain National Forest, southern Missouri, 1988-93

Background hydrologic data were collected from 1988 to 1993 in the Fristoe Unit of the Mark Twain National Forest. Water-quality data collected from area streams, springs, and wells were analyzed using trilinear diagrams, stiff diagrams, boxplots, and summary statistics. The water is a calcium- magnesium-bicarbonate type. Streams generally have slightly larger potassium, barium, and total organic carbon concentrations than spring or well water. Well water has larger bicarbonate and zinc concen- trations and larger variability in sodium, chloride, and nitrate concentrations than stream and spring water samples. The bulk mineralogy for streambed material is primarily coarse grain quartz. Quantitative elemental (chemistry) analysis on the less than 63 micrometer fraction of bulk material was performed. The heavy mineral concentrate in the streambed material was analyzed using semi- quantitative optical mineralogy and 37-element semi- quantitative emission spectrography. Water levels were measured in 57 area wells in the spring and fall from 1990 to 1993 to determine ground-water level fluctuations. Ground-water fluctuations ranged from less than 1.0 to 205.1 feet in these wells. Continuous water-level recorders were installed on three area wells. Depth to water ranged from 289.68 to 333.39 feet in the lower Eleven Point well, which is completed in the Ozark aquifer. Depth to water ranged from 78.73 to 90.20 feet in Ozark Lead Well 1 which is completed in the Ozark aquifer and St. Francois confining unit. Depth to water ranged from 127.53 to 135.67 feet in Ozark Lead Well 2, which is completed in the St. Francois confining unit and the St. Francois aquifer.

Open-File Report↗