Change in Field Turbidity and Trace Element Concentrations During Well Purging   总被引：1，自引：0，他引：1  

Jacob Gibs  Zoltan Szabo  Tamara Ivahnenko  Franceska D. Wilde 《Ground water》2000,38(4):577-588

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Linking meteorites to their asteroid parent bodies: The capabilities of dust analyzer instruments during asteroid flybys     

Lisa Maria Eckart  Jon K. Hillier  Frank Postberg  Simone Marchi  Zoltan Sternovsky 《Meteoritics & planetary science》2023,58(10):1449-1468

Linking meteorites to their asteroid parent bodies remains an outstanding issue. Space-based dust characterization using impact ionization mass spectrometry is a proven technique for the compositional analysis of individual cosmic dust grains. Here we investigate the feasibility of determining asteroid compositions via cation mass spectrometric analyses of their dust ejecta clouds during low (7–9 km s⁻¹) velocity spacecraft flybys. At these speeds, the dust grain mass spectra are dominated by easily ionized elements and molecular species. Using known bulk mineral volume abundances, we show that it is feasible to discriminate the common meteorite classes of carbonaceous chondrites, ordinary chondrites, and howardite–eucrite–diogenite achondrites, as well as their subtypes, relying solely on the detection of elements with ionization efficiencies of ≤700 or ≤800 kJ mol⁻¹, applicable to low (~7 km s⁻¹) and intermediate (~9 km s⁻¹) flyby speed scenarios, respectively. Including the detection of water ion groups enables greater discrimination between certain meteorite types, and flyby speeds ≥10 km s⁻¹ enhance the diagnostic capabilities of this technique still further. Although additional terrestrial calibration is required, this technique may allow more unequivocal asteroid-meteorite connections to be determined by spacecraft flybys, emphasizing the utility of dust instruments on future asteroid missions.  相似文献   

Speleothems and pine trees as sensitive indicators of environmental pollution – A case study of the effect of uranium-ore mining in Hungary     

Zoltan Siklosy  Zoltan Kern  Attila Demeny  Sebastian Pilet  Szabolcs Leel-Ossy  Ke Lin  Chuan-Chou Shen  Eva Szeles  Daniel Breitner 《Applied Geochemistry》2011,26(5):666-678

Four decades of U ore production in Hungary provides an opportunity to study the possible environmental effects of mining. The study reveals significant changes in chemical composition of a stalagmite (cave deposit). The good fit between U content changes in the studied deposit and the U ore production rate support the assumption of the relationship with mining activity. An independent chemoenviromental archive, living pine (Pinus sylvestis) trees were also investigated. Data on pine tree cores collected from the same region show different levels of pollution (Cu, Zn, Mn, U) after the 1950s and 1960s, linked to the opening of mines and subsequent dust fallout around the site. Elevated concentrations of detritally derived elements (Si, Al, Th) coupled with a rise in U concentration and change in δ²³⁴U values of the stalagmite suggest increasing amounts of mine-derived dust from 1 to 3 km distance that settled and washed into the karst system. The combined usage of different proxies not only provides historic records for the anthropogenic impact in the environment, but also allows the timing of U concentration increases within the stalagmite and the identification of elemental behavior from the pollution. This study shows that complementary geochemical archives such as stalagmites and tree rings used together can enhance understanding of past environmental contamination.  相似文献   

Attenuation of multiple ScS in various parts of the world   总被引：1，自引：0，他引：1  

W. Winston Chan  Zoltan A. Der 《Geophysical Journal International》1988,92(2):303-314

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Cosmological physics with black holes (and possibly white dwarfs)     

Kristen Menou  Zoltan Haiman  Bence Kocsis 《New Astronomy Reviews》2008,51(10-12):884

The notion that microparsec-scale black holes can be used to probe gigaparsec-scale physics may seem counterintuitive, at first. Yet, the gravitational observatory LISA will detect cosmologically-distant coalescing pairs of massive black holes, accurately measure their luminosity distance and help identify an electromagnetic counterpart or a host galaxy. A wide variety of new black hole studies and a gravitational version of Hubble’s diagram become possible, if host galaxies are successfully identified. Furthermore, if dark energy is a manifestation of large-scale modified gravity, deviations from general relativistic expectations could become apparent in a gravitational signal propagated over cosmological scales, especially when compared to the electromagnetic signal from a same source. Finally, since inspirals of white dwarfs into massive black holes at cosmological distances may permit pre-merger localizations, we suggest that careful monitoring of these events and any associated electromagnetic counterpart could lead to high-precision cosmological measurements with LISA.  相似文献   

Magnetic properties of high-Ti basaltic rocks from the Krušné hory/Erzgebirge MTS. (Bohemia/Saxony), and their relation to mineral chemistry     

Petr Schnabl  Jiří K. Novák  Vladimír Cajz  Miloš Lang  Kadosa Balogh  Zoltan Pécskay  Martin Chadima  Stanislav Šlechta  Tomáš Kohout  Petr Pruner  Jaromír Ulrych 《Studia Geophysica et Geodaetica》2010,54(1):77-94

This study provides new thermomagnetic and petrographic data on specific basaltic rock association from the broader vicinity of the Lou?ná-Oberwiesenthal volcanic centre, western Bohemia/Saxony. Two types of volcanic rocks were recognized there: (i) high-Ti types (3.5–5.2 wt% TiO₂) represented by (mela)nephelinite s.s., and sporadically present (ii) medium-Ti types (2.5–3.5 wt% TiO₂) of olivine nephelinite, nepheline basanite and phonotephrite compositions. In order to examine the rock-magnetic behaviour, they were studied for their variations in the Curie temperature (T_C) and field-dependent susceptibility, spinel group minerals, chemistry and petrology. Magnetic susceptibility of ulvöspinel-rich titanomagnetite, as a dominant magnetic carrier, depends on the amplitude of measured magnetic field, whereas pure magnetite is field-independent. Field dependence parameter ^kHD of the studied basaltic rocks ranges from 0.8 to 18.7%, TiO₂ contents in titanomagnetite range from 12.7 to 20.1 wt.%. TiO₂ content in titanomagnetite does not correlate with whole-rock TiO₂ content (2.8 to 5.6 wt.%). The content of substituted titanium in the sublattice of magnetite is also sensitively reflected in the Curie temperature, ranging from 200 to 580°C. The spinel group minerals are designated as titanomagnetite with the dominance of ulvöspinel, magnetite and magnesioferrite components, or titanomagnetite with the magnetite, ulvöspinel and magnesioferrite components. Only two samples are characterized by a significant presence of Cr-spinel and magnesiochromite components forming cores of titanomagnetites. The titanomagnetite-bearing rocks in the studied area, likewise the low- to medium-Ti basaltic rocks from the ?eské st?edoho?í Mts., provide similar thermomagnetic curves.  相似文献   

Impact of AMD on water quality in critical watershed in the Hudson River drainage basin: Phillips Mine,Hudson Highlands,New York   总被引：1，自引：0，他引：1  

Sivajini Gilchrist  Alexander Gates  Zoltan Szabo  Paul J. Lamothe 《Environmental Geology》2009,57(2):397-409

A sulfur and trace element enriched U–Th-laced tailings pile at the abandoned Phillips Mine in Garrison, New York, releases acid mine drainage (AMD, generally pH < 3, minimum pH 1.78) into the first-order Copper Mine Brook (CMB) that drains into the Hudson River. The pyrrhotite-rich Phillips Mine is located in the Highlands region, a critical water source for the New York metro area. A conceptual model for derivation/dissolution, sequestration, transport and dilution of contaminants is proposed. The acidic water interacts with the tailings, leaching and dissolving the trace metals. AMD evaporation during dry periods concentrates solid phase trace metals and sulfate, forming melanterite (FeSO₄·7H₂O) on sulfide-rich tailings surfaces. Wet periods dissolve these concentrates/precipitates, releasing stored acidity and trace metals into the CMB. Sediments along CMB are enriched in iron hydroxides which act as sinks for metals, indicating progressive sequestration that correlates with dilution and sharp rise in pH when mine water mixes with tributaries. Seasonal variations in metal concentrations were partly attributable to dissolution of the efflorescent salts with their sorbed metals and additional metals from surging acidic seepage induced by precipitation.  相似文献   

Implications of particle acceleration in active galactic nuclei for cosmic rays and high energy neutrino astronomy     

A. P. Szabo  R. J. Protheroe 《Astroparticle Physics》1994,2(4):375-392

We consider the production of high energy neutrinos and cosmic rays in radio-quiet active galactic nuclei (AGN) or in the central regions of radio-loud AGN. We use a model in which acceleration of protons takes place at a shock in an accretion flow onto a supermassive black hole, and follow the cascade that results from interactions of the accelerated protons in the AGN environment. We use our results to estimate the diffuse high energy neutrino intensity and cosmic ray intensity due to AGN. We discuss our results in the context of high energy neutrino telescopes under construction, and measurements of the cosmic ray composition in the region of the “knee” in the energy spectrum at 10⁷ GeV.  相似文献   

Theory for Errors, Resolution, and Separation of Unknown Variables in Inverse Problems, with Application to the Mantle and the Crust in Southern Africa and Scandinavia     

Zoltan A. Der  M. Landisman 《Geophysical Journal International》1972,27(2):137-178

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Comments on 'P-wave amplitudes in the United States: east–west variations and variability', by Rhett Butler     

Zoltan A. Der 《Geophysical Journal International》1985,81(2):381-383

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