Stable isotopes of water as a tool to study groundwater–seawater interactions in coastal south-eastern Sicily     

M.A. Schiavo  S. Hauser  P.P. Povinec 《Journal of Hydrology》2009,364(1-2):40-49

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VARNET-96: influence of the Variscan and Caledonian orogenies on crustal structure in SW Ireland   总被引：1，自引：0，他引：1  

Michael Landes  C. Prodehl  F. Hauser  A. W. B. Jacob  & N. J. Vermeulen 《Geophysical Journal International》2000,140(3):660-676

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Water Table Uncertainties due to Uncertainties in Structure and Properties of an Unconfined Aquifer          下载免费PDF全文

Juerg Hauser  Florian Wellmann  Mike Trefry 《Ground water》2018,56(2):251-265

We consider two sources of geology‐related uncertainty in making predictions of the steady‐state water table elevation for an unconfined aquifer. That is the uncertainty in the depth to base of the aquifer and in the hydraulic conductivity distribution within the aquifer. Stochastic approaches to hydrological modeling commonly use geostatistical techniques to account for hydraulic conductivity uncertainty within the aquifer. In the absence of well data allowing derivation of a relationship between geophysical and hydrological parameters, the use of geophysical data is often limited to constraining the structural boundaries. If we recover the base of an unconfined aquifer from an analysis of geophysical data, then the associated uncertainties are a consequence of the geophysical inversion process. In this study, we illustrate this by quantifying water table uncertainties for the unconfined aquifer formed by the paleochannel network around the Kintyre Uranium deposit in Western Australia. The focus of the Bayesian parametric bootstrap approach employed for the inversion of the available airborne electromagnetic data is the recovery of the base of the paleochannel network and the associated uncertainties. This allows us to then quantify the associated influences on the water table in a conceptualized groundwater usage scenario and compare the resulting uncertainties with uncertainties due to an uncertain hydraulic conductivity distribution within the aquifer. Our modeling shows that neither uncertainties in the depth to the base of the aquifer nor hydraulic conductivity uncertainties alone can capture the patterns of uncertainty in the water table that emerge when the two are combined.  相似文献   

The Etesians: from observations to reanalysis     

Stella Dafka  Elena Xoplaki  Andrea Toreti  Prodromos Zanis  Evangelos Tyrlis  Christos Zerefos  Juerg Luterbacher 《Climate Dynamics》2016,47(5-6):1569-1585

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Semiconductors exposed to oils in pressure-tolerant electronic systems     

Daniel E. Gilbert  John R. Hauser  James W. Harrison  Jimmie J. Wortman 《Ocean Engineering》1974,2(6):265-273

The present study indicates that most semiconductor components are fabricated such that they are not affected by operation in a dielectric oil environment. A quantitative estimate of the conditions under which oil-soluble ions will invert semiconductor surfaces and interfere with proper device operation is developed. The results are discussed in terms of pressure-tolerant electronic systems—solid-state components operated immersed in chemically inert dielectric oils when these components are subject to, and experience, ambient hydrostatic pressures of the ocean depths. The feasibility of pressure-tolerant electronic systems is demonstrated.  相似文献   

Linking shock textures revealed by BSE,CL, and EBSD with U‐Pb data (LA‐ICP‐MS and SIMS) from zircon from the Araguainha impact structure,Brazil     

Natalia Hauser  Wolf Uwe Reimold  Aaron J. Cavosie  Alvaro P. Crsta  Winfried H. Schwarz  Mario Trieloff  Carolinna Da Silva Maia de Souza  Luciana A. Pereira  Eduardo N. Rodrigues  Matthews Brown 《Meteoritics & planetary science》2019,54(10):2286-2311

A silicious impact melt rock from polymict impact breccia of the northern part of the alkali granite core of the Araguainha impact structure, central Brazil, has been investigated. The melt rock is thought to represent a large mass of impact‐generated melt in suevite. In particular, a diverse population of zircon grains, with different impact‐induced microstructures, has been analyzed for U‐Pb isotopic systematics. Backscattered electron and cathodoluminescence images reveal heterogeneous intragrain domains with vesicular, granular, vesicular plus granular, and vesicular plus (presumably) baddeleyite textures, among others. The small likely baddeleyite inclusions are not only preferentially located along grain margins but also occur locally within grain interiors. LA‐ICP‐MS U‐Pb data from different domains yield lower intercept ages of 220, 240, and 260 Ma, a result difficult to reconcile with the previous “best age” estimate for the impact event at 254.7 ± 2.7 Ma. SIMS U‐Pb data, too, show a relatively large range of ages from 245 to 262 Ma. A subset of granular grains that yielded concordant SIMS ages were analyzed for crystallographic orientation by EBSD. Orientation mapping shows that this population consists of approximately micrometer‐sized neoblasts that preserve systematic orientation evidence for the former presence of the high‐pressure polymorph reidite. In one partially granular grain (#36), the neoblasts occur in linear arrays that likely represent former reidite lamellae. Such grains are referred to as FRIGN zircon. The best estimate for the age of the Araguainha impact event from our data set from a previously not analyzed type of impact melt rock is based on concordant SIMS data from FRIGN zircon grains. This age is 251.5 ± 2.9 Ma (2σ, MSWD = 0.45, p = 0.50, n = 4 analyses on three grains), indistinguishable from previous estimates based on zircon and monazite from other impact melt lithologies at Araguainha. Our work provides a new example of how FRIGN zircon can be combined with in situ U‐Pb geochronology to extract an accurate age for an impact event.  相似文献   

Origin of components in Chilean thermal waters     

François Risacher  Bertrand Fritz  Arturo Hauser 《Journal of South American Earth Sciences》2011,31(1):153-170

Thermal waters of northern (18°–27°S) and southern (37°–45°S) Chile occur in two very different climatic, geologic and hydrologic environments: arid closed basins with abundant evaporites in the north; humid climate and well drained valleys in the south. The origin and behavior of the main components of the two groups of waters are examined and compared to each other. The modeling of the alteration of volcanic rocks leads to water compositions very different from those observed both in the north and south. In addition to hydrothermal alteration and deep emanations, the Cl/Br ratio reveals a major contribution of saline waters to the two groups: infiltrating brines from salt lakes in the north; seawater in the south.In the north, concentrations of Cl, Br, Na, K, Ca, SO₄, Li, B, Si result from the mixing of alteration waters with recycled brines. Hydrothermal alteration is obscured by this massive saline input, except for Mg. δ³⁴S values are consistent with an origin of sulfate from salar brines, which are themselves derived from deep Tertiary gypsum. In the south, two processes account for the composition of thermal waters: mixing of alteration waters with seawater and deep magmatic contribution. The mixing process controls the concentration of Cl, Br, Na, Alk, Si, K, Ca, Mg. Magmatic inputs are detectable for SO₄, Li and B. δ³⁴S suggests that sulfate stems from the mixing of alteration waters with either marine SO₄ in coastal waters or with deep SO₂ in inland waters. In both the north and south, the Mg concentration is drastically lowered (<1 μmol/L) by the probable formation of a chlorite-type mineral. In the south, very small amounts of seawater (<1% in volume) are sufficient to imprint a clear signature on thermal waters. Not only coastal springs are affected by seawater mixing, but also remote inland springs, as far as 150 km from the sea. Subduction of marine sediments in the accretive margin could be the source of the marine imprint in thermal waters of southern Chile. Seawater may be expelled from the subducted lithosphere and incorporated into the mantle source.  相似文献   

Morphological and spectral studies of the shell-type supernova remnants RX J1713.7–3946 and RX J0852.0–4622 with H.E.S.S.     

M. Lemoine-Goumard  F. Aharonian  D. Berge  B. Degrange  D. Hauser  N. Komin  O. Reimer  U. Schwanke 《Astrophysics and Space Science》2007,309(1-4):379-384

In 2004 and 2005, the shell-type supernova remnants RX J1713.7–3946 and RX J0852.0–4622 were observed and detected with the complete H.E.S.S. array, a system of four Imaging Cherenkov Telescopes located in Namibia and dedicated to the observations of γ-rays above 100 GeV. The energy spectra of these two sources have been measured over a wide energy range and revealed an integral flux above 1 TeV similar to that of the Crab Nebula. Their morphologies were resolved with high accuracy with H.E.S.S. and exhibit a striking correlation with the X-ray images, thereby pioneering a technique of unambiguously identifying spatially extended γ-ray sources. The results of the observations will be presented. Similarities and differences between these two sources will be pointed out as well as possible implications. M. Lemoine-Goumard, F. Aharonian, D. Berge, B. Degrange, D. Hauser, N. Komin, O. Reimer, U. Schwanke for the H.E.S.S. Collaboration  相似文献   

One-millimeter brightness temperatures of the planets     

M.W. Werner  G. Neugebauer  J.R. Houck  M.G. Hauser 《Icarus》1978,35(3):289-296

New values for the 1-mm brightness temperatures of Mercury, Venus, Jupiter, Saturn, Uranus, and Neptune have been determined using Mars as the absolute photometric standard.  相似文献   

Der steirische Vulkanbogen als magmatische Provinz     

A. Hauser 《Mineralogy and Petrology》1954,4(1-4):301-311

Zusammenfassung Das in jüngster Zeit anläßlich von Bohrungen festgestellte Vulkangebiet Mureck-Retznei schließt eine Lücke im Kranz der vulkanischen Ergüsse, die den Bogen begleiten, an dem die Alpen im Südosten und Osten in die Tiefe sinken. Sicherlich ist das Auftreten des Vulkanismus im steirischen Vulkanbogen nicht beziehungslos zum Niedertauchen der Alpen, sondern vielmehr die Herausstellung eines tektonischen Bereiches, in dem letzten Endes die Wegsamkeit für das Empordringen des Magmas gesucht werden muß. Vom Raume der Drau-Save-Zone und des Bachers erstreckt sich der steirische Vulkanbogen nach Nordosten über Mjreck, Gleichenberg und das Burgenland bis in das Plattenseegebiet. Im südwestlichen Abschnitt konzentriert sich der saure Vulkanismus, der im Raume Gleichenberg in engste räumliche Nachbarschaft zur basaltischen Entfaltung tritt, die die Fortsetzung nach Osten übernimmt. Der steirische Vulkanbogen ist als magmatische Provinz (gemischte Gesteinsprovinz) mit temporaler Dispersion anzusehen.Im steirischen Vulkanbogen hat die Asche den Ursprung, die, über das steirische Tertiär bis in das Grundgebirge verweht, den Stoff für den Aufbau der nicht wenigen Tufflager (u. a. auch verschiedener steirischer Bentonitvorkommen) lieferte. Das Fehlen bauwürdiger Erzlagerstätten im engeren vulkanischen Bereich fällt auf.Mit 1 Übersichtskarte.  相似文献