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FrogwatchUSA

full text: Frogs and toads are perhaps the most approachable and available of all our wildlife. In many, if not most places, they are abundant. In wetter parts of the East, almost anyone outside on a warm rainy night in spring will hear their dream-like calls, bellows, trills and snores. Even in the deserts of the Southwest, a nocturnal trip after a summer monsoon will yield toads moving across the roads toward a cacophonous orgy of mating and calling in the roadside ditches and desert pools. Birds share with frogs and toads this same sense of presence in our daily lives. But the difference is that birds are like the attractive neighbor who just never gives you the time of day, while frogs are more like the troglodyte who appears regularly to chat, philosophize, and have a beer. Uninvited, frogs appear in our water gardens, toads are on our stoops in the morning, we catch them when we are kids, raise their babies in the aquarium, and feel sorry when we find we have run them over with the lawnmower. When concerns about declining populations of amphibians reached the mass media, the Secretaries' office became involved. In addition to using traditional research mechanisms to investigate the problem, the Secretary also wanted to involve the public directly. The combination of high public appeal and the relative ease with which frog calls can be learned made a large-scale monitoring program for frogs and toads possible. What emerged was a program called Frogwatch USA, modeled after a successful Canadian program with a similar name. A web site was created (www.frogwatch.org) that presented potential frogwatchers with directions and a way to register their site online as well as enter their data. Observers chose where to count frogs depending on what they felt was important. For some it was their backyard, others chose vulnerable wetlands in their neighborhoods, or spots on local refuges and parks. Initially funded at $8,000 a year and then after two years increased to $25,000, most of the first part of this program's life was spent developing the tools and web site to document counts of frogs online. Despite the lack of time available to promote the program, send out press releases and recruit observers, news of the program quickly spread by word of mouth and the electronic media. Many newspaper articles later, we found a large number of people had become involved with counting frogs in their neighborhoods and backyards. Current figures show 1,456 observers who have registered at 1,683 sites logging almost 5,000 visits. These visits yield information on when and what species are calling from wetlands throughout the United States. These records are usually the only records of information about frogs and toads for those sites and become a permanent record that can be revisited in future years. Additionally, when observers make a lot of visits or there are many sites in a region, a phenology of calls can be created that documents when it is most likely in that year for each species to be recorded. Finally, even for those observers whose data we may mistrust and therefore are likely to eliminate from analyses, these people have taken the time to leave their televisions, go outside, and directly experience frogs, toads, and all that occur in Nature. In 1999 it was decided that FrogwatchUSA needed to work with another group that specifically focused on environmental education and outreach. After talking to a number of organizations we found that the National Wildlife Federation, with their Backyard Wildlife Habitat, Endangered Species, and other programs along with their four million members who are interested in nature, would be an excellent match. Thus a partnership was born. After over a year of work between Interior and National Wildlife Federation biologists and lawyers, an agreement has been created that places the Federation as the lead of Frogwatch USA. It will now take care of res

People, Land, and Water↗

Anaerobic oxidation of arsenite by autotrophic bacteria: The view from Mono Lake, California

Introduction The phenomenon of arsenite [As(III)] oxidation by aerobic bacteria was first reported by Green (1918), and the many subsequent discoveries made in this realm, most occurring over the past three decades, are the primary focus of this book. In contrast, the fact that select anaerobes can also achieve this feat was an entirely serendipitous discovery. As often occurs in science, the intended path leading towards a stated goal can take an unexpected turn, ultimately leading to greater rewards than those originally anticipated. The intellectual freedom to meander such a path of curiosity-driven research is a great gift especially when one arrives at an unexpected revelation. It is perhaps the most rewarding aspect of a scientist's career. Such was the case when we first uncovered the phenomenon of anaerobic As(III) oxidation. Our arsenic-related field work focused on Mono Lake, California because of its exceptionally high levels of dissolved inorganic arsenic (~200 μM), and the fact that we had previously isolated two novel species of arsenate [As(V)]-respiring bacteria, Bacillus arseniciselenatis and B. selenitireducens from its bottom sediments(Switzer Blum et al. , 1998). Radiotracer investigations employing 73 As(V) measured high As(V) reductase activity in the anoxic water column of the lake, yielding an estimate that this electron sink could mineralize approximately 8-14% of annual phytoplankton productivity (Oremland et al. , 2000), a value confirmed independently on the basis of mass balance considerations (Hollibaugh et al. , 2005). In both studies both groups also used cultivation-based methods (Most-Probable-Numbers) to estimate the densities of As(V)-respiring bacteria in the anoxic water column, and arrived at similar low but detectable values (e.g. 10 2 -10 3 ml -1 ). The next goal was to determine what taxa of As(V)-respiring prokaryotes were involved in these water-column transformations, using culture-independent analyses (Denaturing Gradient Gel Electrophoresis) of As(V)-amended anoxic bottom water. We had expected to find 16S rRNA gene amplicon sequences similar to those from the bacilli we isolated from the sediments, but instead found a few rather unremarkable amplicons in the Epsilon, Gamma and Delta proteobacteria; yet these incubations showed a complete reduction of the added As(V), caused by sulfide-linked oxidation by resident chemoautotrophs of the Delta-proteobacteria (Hoeft et al. , 2004; Hollibaugh et al. , 2006). This As(V) reductase activity was inhibited by nitrate, while addition of As(III) to nitrate-amended waters resulted in the formation of As(V). This observation led us to conclude that there was anaerobic biological oxidation of As(III) to As(V), linked to the provided nitrate ions (Hoeft et al. , 2002).

California↗

SUBMICROSCOPIC ( less than 1 mu m) MINERAL CONTENTS OF VITRINITES IN SELECTED BITUMINOUS COAL BEDS.

An important aspect of the petrographic description of coal is the characterization of coal quality, including chemical attributes. For geologic investigations, data on the concentrations, distribution, and modes of occurrence of minor and trace elements provide a basis for reconstructing the probable geochemical environment of the swamp material that was converted into peat, and the geochemical conditions that prevailed during and subsequent to coalification. We have been using electron (EPMA) and proton (PIXE) microprobe analytical methods to obtain data on the chemical characteristics of specific coal constituents in their original associations within coal samples. The present study is aimed at evaluation of the nature of mineral occurrences and heterogeneous elemental concentrations within vitrinites. Vitrinites are usually the most abundant, and therefore most important, maceral group in bituminous coal. 8 refs.

Conference Paper↗

AQUATIC PHOTOLYSIS OF OXY-ORGANIC COMPOUNDS ADSORBED ON GOETHITE.

Organic materials that will not absorb light at wavelengths longer than 295 nanometers (the solar wavelength cutoff) may nevertheless, undergo electron transfer reactions initiated by light. These reactions occur when the organic materials are adsorbed as ligand complexes to the surface of iron oxy-hydroxide (goethite). The adsorbed materials can be either inner or outer coordination sphere complexes. Goethite was chosen as the iron oxyhydroxide surface because it has the highest thermodynamic stability of any of the oxyhydroxides in water and it can be synthesized easily, with high purity.

Conference Paper↗

Ostwald ripening and interparticle-diffraction effects for illite crystals

The Warren-Averbach method, an X-ray diffraction (XRD) method used to measure mean particle thickness and particle-thickness distribution, is used to restudy sericite from the Silverton caldera. Apparent particle-thickness distributions indicate that the clays may have undergone Ostwald ripening and that this process has modified the K-Ar ages of the samples. The mechanism of Ostwald ripening can account for many of the features found for the hydrothermal alteration of illite. Expandabilities measured by the XRD peak-position method for illite/smectites (I/S) from various locations are smaller than expandabilities measured by transmission electron microscopy (TEM) and by the Warren-Averbach (W-A) method. This disparity is interpreted as being related to the presence of nonswelling basal surfaces that form the ends of stacks of illite particles (short-stack effect), stacks that, according to the theory of interparticle diffraction, diffract as coherent X-ray scattering domains. -from Authors

American Mineralogist↗

Akermanite: phase transitions in heat capacity and thermal expansion, and revised thermodynamic data.

A small but sharp anomaly in the heat capacity of akermanite at 357.9 K, and a discontinuity in its thermal expansion at 693 K, as determined by XRD, have been found. The enthalpy and entropy assigned to the heat-capacity anomaly, for the purpose of tabulation, are 679 J/mol and 1.9 J/(mol.K), respectively. They were determined from the difference between the measured values of the heat capacity in the T interval 320-365 K and that obtained from an equation which fits the heat-capacity and heat-content data for akermanite from 290 to 1731 K. Heat-capacity measurements are reported for the T range from 9 to 995 K. The entropy and enthalpy of formation of akermanite at 298.15 K and 1 bar are 212.5 + or - 0.4 J/(mol.K) and -3864.5 + or - 4.0 kJ/mol, respectively. Weak satellite reflections have been observed in hk0 single-crystal X-ray precession photographs and electron-diffraction patterns of this material at room T. With in situ heating by TEM, the satellite reflections decreased significantly in intensity above 358 K and disappeared at about 580 K and, on cooling, reappeared. These observations suggest that the anomalies in the thermal behaviour of akermanite are associated with local displacements of Ca ions from the mirror plane (space group P421m) and accompanying distortion of the MgSi2O7 framework.-L.C.C.

Canadian Mineralogist↗

DEBRIS FLOWS AND HYPERCONCENTRATED STREAMFLOWS.

Examination of recent debris-flow and hyperconcentrated-streamflow events in the western United States reveals (1) the topographic, geologic, hydrologic, and vegetative conditions that affect initiation of debris flows and (2) the wide ranging climatic conditions that can trigger debris flows. Recognition of these physiographic and climatic conditions has aided development of preliminary methods for hazard evaluation. Recent developments in the application of electronic data gathering, transmitting, and processing systems shows potential for real-time hazard warning.

Conference Paper↗

Aluminum in hornblende: an empirical igneous geobarometer.

Electron-microprobe analyses of hornblendes from five calc-alkaline plutonic complexes representing low- and high-pressure regimes define a tightly clustered linear trend in terms of total Al (AlT) and tetrahedral Al (Aliv) contents. Data collated from the literature on calcic amphiboles from other plutonic complexes and from phase equilibrium experiments using natural rocks or synthetic analogue compositions show a similar AlT-Aliv trend and systematic pressure effects.-J.A.Z.

American Mineralogist↗

Pb-Bi-Ag-Cu-(Hg) chemistry of galena and some associated sulfosalts. A review and some new data from Colorado California and Pennsylvania

Galena, associated with Pb-Bi-Ag sulfosalts and simple sulfides, contains varied amounts of Ag and Bi in the Dandy vein system, Idarado mine, Ouray, Colorado; the Jackass mine, Darwin District, California; and the Leadville district, Colorado. Silver- and bismuth-bearing galena associated with minor amounts of pyrite, chalcopyrite and sphalerite occur at the Pequea mine, Lancaster County, Pennsylvania. Ag and Bi contents in the Dandy suite of galena range from about 1.4 to 3.4 and 2.5 to 6.5 wt.% respectively, and are comparable or lower in galena from the other localities. Exsolved matildite is present in galena from the Dandy, Jackass and Leadville localities. The presence in significant amounts of both Ag and Bi in a Pb-rich sulfide system is necessary for formation of PbSss (galena solid-solution). If Ag (especially) and Bi (to a lesser extent) are absent, the galena formed will be essentially pure PbS. Some minor Sb may substitute for Bi. Compositional data for all of the galena samples are in agreement with a previously proposed linear relationship between a and Ag-Bi(Sb) content. Matildite and seven additional Pb-Bi-Ag-Cu sulfosalts have been identified from the Dandy vein system, based on electron-microprobe analyses and some X-ray powder-diffraction data.

Canadian Mineralogist↗

Molecular orbital (SCF-X-α-SW) theory of Fe 2+- Mn 3+ , Fe 3+- Mn 2+ , and Fe 3+- Mn 3+ charge transfer and magnetic exchange in oxides and silicates

Metal-metal charge-transfer and magnetic exchange interactions have important effects on the optical spectra, crystal chemistry, and physics of minerals. Previous molecular orbital calculations have provided insight on the nature of Fe2+-Fe3+ and Fe2+-Ti4+ charge-transfer transitions in oxides and silicates. In this work, spin-unrestricted molecular orbital calculations on (FeMnO10) clusters are used to study the nature of magnetic exchange and electron delocalization (charge transfer) associated with Fe3+-Mn2+, Fe3+-Mn3+, and Fe2+-Mn3+ interactions in oxides and silicates.

American Mineralogist↗

New hydrologic instrumentation in the U.S. Geological Survey

New water-level sensing and recording instrumentation is being used by the U.S. Geological Survey for monitoring water levels, stream velocities, and water-quality characteristics. Several of these instruments are briefly described. The Basic Data Recorder (BDR) is an electronic data logger, that interfaces to sensor systems through a serial-digital interface standard (SDI-12), which was proposed by the data-logger industry; the Incremental Shaft Encoder is an intelligent water-level sensor, which interfaces to the BDR through the SDI-12; the Pressure Sensor is an intelligent, nonsubmersible pressure sensor, which interfaces to the BDR through the SDI-12 and monitors water levels from 0 to 50 feet; the Ultrasonic Velocity Meter is an intelligent, water-velocity sensor, which interfaces to the BDR through the SDI-12 and measures the velocity across a stream up to 500 feet in width; the Collapsible Hand Sampler can be collapsed for insertion through holes in the ice and opened under the ice to collect a water sample; the Lighweight Ice Auger, weighing only 32 pounds, can auger 6- and 8-inch holes through approximately 3.5 feet of ice; and the Ice Chisel has a specially hardened steel blade and 6-foot long, hickory D-handle.

Conference Paper↗

Crystalline solution series and order-disorder within the natrolite mineral group

Electron microprobe and X-ray analyses were made of natrolite, tetranatrolite, gonnardite, and thomsonite from the Magnet Cove alkaline igneous complex, Arkansas, and of selected specimens from the U.S. National Museum. This information and data from the literature indicate that natrolite, mesolite, scolecite, edingtonite, and tetraedingtonite show only small deviations from the ideal stoichiometry. In contrast, gonnardite, tetranatrolite, and thomsonite show large deviations from the ideal end-member compositions and compose three crystalline series. The structures of the natrolite minerals are defined by combining each of the three types of framework structures with various combinations of channel-occupying polyhedra. Various polysomatic series can be constructed by combining slices of two basic structures to form new hybrid structures. -from Authors

American Mineralogist↗

Hydrothermal and metamorphic berthierine from the Kidd Creek volcanogenic massive sulfide deposit, Timmins, Ontario

Berthierine, a 7 A?? Fe-Al member of the serpentine group, occurs in the footwall stringer zone of the Archean Kidd Creek massive sulfide deposit, associated with quartz, muscovite, chlorite, pyrite, sphalerite, chalcopyrite, and local tourmaline, cassiterite, and halloysite. Petrographic and scanning electron microscopic (SEM) studies reveal different types of berthierine occurrences, including interlayers within the rims on deformed chlorite, intergrowths with muscovite and halloysite, and discrete coarse grains. This is the first reported occurrence of berthierine from volcanogenic massive sulfide deposits. Textural relations suggest that most of the berthierine formed as a primary hydrothermal mineral at relatively high temperatures (~350??C) in the footwall stringer zone, probably by the replacement of a pre-existing aluminous phase such as muscovite or chlorite. However, the intergrowth textures observed by SEM and TEM suggest that some of the berthierine originated by syn- or post-metamorphic replacement of chlorite. -from Authors

Canadian Mineralogist↗

Water, CO2, Cl, and F in melt inclusions in phenocrysts from three Holocene explosive eruptions, Crater Lake, Oregon

Rare melt inclusions ~ 100 μ m in diameter trapped near the boundaries of corroded patchy zones in plagioclase phenocrysts from Plinian pumice of three Holocene eruptions were analyzed by IR spectroscopy for molecular H 2 O, OH groups, and CO 2 and by electron microprobe for Cl and F. The three rhyodacitic eruptions, each of which began with a Plinian phase, occurred over ~200 yr. The Llao Rock and Cleetwood eruptions ended with degassed lava flows and the subsequent climactic eruption with voluminous ignimbrite. Groundmass glass and melt inclusion compositions (anhydrous) are similar. Inclusions with total H 2 O concentrations of 1.2–3.4 wt% are adjacent to fractures or are hourglass inclusions, suggesting partial degassing caused by depressurization. Melt inclusions in phenocrysts in climactic ignimbrite may have vesiculated for the same reason. Intact inclusions in Plinian pumices have total H 2 O concentrations believed to represent magmatic H 2 O contents (wt%): Llao Rock, 5.3, 5.3; Cleetwood,3.8,4.7; climactic 3.9 ± 0.2 (1 σ, n = 6). Ratios of OH/molecular H 2 O indicate closure temperatures of 200–500 °C that reflect syn- or posteruptive cooling. CO 2 concentrations are ≤25 ppm. H 2 O and CO 2 concentrations indicate saturation pressures of 1.0–1.8 kbar or depths ≥5 km. Six inclusions from climactic pumice average 400 ± 40 (1 σ ) ppm F, 1880 ± 70 ppm Cl. F and Cl concentrations of the other samples are similar and not well correlated with each other or with total H 2 O. Location of melt inclusions near boundaries of patchy zones, which are mantled by oscillatory-zoned overgrowths, suggests that their H 2 O concentrations represent magmatic values significantly before eruption. Although mean H 2 O concentrations of analyzed melt inclusions decrease for the three successive eruptions, it is not certain that this indicates a corresponding change in magmatic H 2 O content during the interval between eruptions.

Oregon↗

Managing the data explosion

The 'data explosion' brought on by electronic sensors and automatic samplers can strain the capabilities of existing water-quality data-management systems just when they're needed most to process the information. The U.S. Geological Survey has responded to the problem by setting up an innovative system that allows rapid data analysis.

Civil Engineering↗

Roof-rock contamination of Taylor Creek Rhyolite, New Mexico, as recorded in hornblende phenocrysts and biotite xenocrysts

The Taylor Creek Rhyolite, a group of coeval, mid-Tertiary, silica-rich rhyolite lava domes in southwestern New Mexico, is notable for recording bulk-rock evidence of minor, yet easily measurable, contamination of its source magma reservoir resulting from assimilation of Proterozoic roof rock. Most of the evidence is recorded in trace element concentrations and 87Sr/86Sri ratios, which are far different in unconlaminated magma and roof rocks. Hornblende phenocrysts and biotite xenocrysts also record the effects of contamination. Electron microprobe analyses show that all hornblende grains are zoned to Mg-rich and Fe- and Mn-poor rims. Rim MgO content is typically about 10 wt% greater than core MgO content. Other hornblende constituents are not measurably variable. Biotite xenocrysts, trace mineral constituents, are present only in the domes that are most contaminated, as judged by bulk-rock variations in trace element concentrations and 87Sr/ 86Sri. Biotite grains are invariably partly to almost completely altered. Microprobe analyses of the cores of the least-altered grains show that large variations in Fe and Mg and that biotite contains 2-20 times as much Mg as fresh biotite phenocrysts in other silica-rich rhyolite lavas. Fe and Mg are negatively correlated in hornblende and biotite, consistent with mixing two end-member compositions. The mass ratio of contaminant to magma was probably less than 1:100, and major constituents, including Al, were not measurably affected in hornblende. Al-in-hornblende barometry yields essentially a constant calculated pressure of about 1.5 kbar, which is consistent with the interpretation that all contamination occurred in a boundary zone about 300 m thick at the top of the magma reservoir.

American Mineralogist↗

Mn-rich ilmenite from the Sullivan Pb-Zn-Ag deposit, British Columbia

Electron-microprobe analyses of 76 ilmenite grains from 13 locations in the footwall, hanging wall, and ore zone of the Sullivan Pb-Zn-Ag deposit, Kimberley, British Columbia, and from regionally developed tourmalinite of the Middle Proterozoic Aldridge Formation show two different modes that reflect two stages of formation. The first stage of ilmenite formation occurred as a result of greenschist-facies regional metamorphism, which also produced the associated Mn-rich garnet. Ilmenite from this stage forms inclusions within garnet and has a relatively low Mn content (<5.5 wt% MnO), owing to the preferential partitioning of Mn into the garnet. A second metamorphic or hydrothermal event resulted in the formation of ilmenite-bearing veinlets (+ chlorite + quartz + sulfides) that cut garnet and associated biotite. This latter type of ilmenite has a higher Mn content (up to 16.7 wt% MnO) that reflects remobilization of Mn within the local environment. Both types of Mn-rich ilmenite are considered to be derived from Mn originally concentrated in pools of dense brine that formed during synsedimentary, submarine-exhalative mineralization.

Canadian Mineralogist↗

Fluor-ferro-leakeite, NaNa2(FC2+2Fe3+2Li)Si8O22F2, a new alkali amphibole from the Canada Pinabete pluton, Questa, New Mexico, U.S.A.

Fluor-ferro-leakeite is a new amphibole species from the Canada Pinabete pluton, Questa, New Mexico, U.S.A.; it occurs in association with quartz, alkali feldspar, acmite, ilmenite, and zircon. It forms as anhedral bluish black crystals elongated along c and up to 1 mm long. It is brittle, H = 6, Dmeas = 3.37 g/cm3, Dcalc = 3.34 g/cm3. In plane-polarized light, it is strongly pleochroic, X = very dark indigo blue, Y = gray blue, Z = yellow green; X ??? c = 10?? (in ??obtuse), Y = b, Z ??? a = 4?? (in ?? obtuse), with absorption X > Y > Z. Fluor-ferro-leakeite is biaxial positive, ?? = 1.675(2), ??= 1.683(2), ?? = 1.694(1); 2V = 87(2)??; dispersion is not visible because of the strong absorption. Fluor-ferro-leakeite is monoclinic, space group C2/m, a = 9.792(1), b = 17.938(1), c = 5.3133(4) A??, ??= 103.87(7)??, V = 906.0(1) A??3, Z = 2. The ten strongest X-ray diffraction lines in the powder pattern are [d(I,hkl)]: 2.710(100,151), 2.536(92,202), 3.404(57,131), 4.481(54,040), 8.426(45,110), 2.985(38,241), 2.585(38,061), 3.122(29,310), 2.165(26,261), and 1.586(25,403). Analysis by a combination of electron microprobe, ion microprobe, and crystal-structure refinement (Hawthorne et al. 1993) gives SiO2 51.12, Al2O3 1.13, TiO2 0.68, Fe2O3 16.73, FeO 8.87, MgO 2.02, MnO 4.51, ZnO 0.57, CaO 0.15, Na2O 9.22, K2O 1.19, Li2O 0.99, F 2.87, H2Ocalc 0.60, sum 99.44 wt%. The formula unit, calculated on the basis of 23 O atoms, is (K0.23Na0.76)(Na1.97Ca0.03)(Mg 0.46Fe2+1.4Mn2+0.59Zn0.07Fe3+1.93-Ti 0.08Al0.02Li0.61])(Si7.81Al 0.19)O22(F1.39OH0.61). A previous crystal-structure refinement (Hawthorne et al. 1993) shows Li to be completely ordered at the M3 site. Fluor-ferro-leakeite, ideally NaNa2(Fe2+2Fe3+2Li)Si8O22F2, is related to leakeite, NaNa2(Mg2Fe3+3Li)Si 8O22(OH)2, by the substitutions Fe2+ ??? Mg and F ??? OH.

American Mineralogist↗