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C. V.?ChrysikopoulosEmail author E. T.?Vogler 《Stochastic Environmental Research and Risk Assessment (SERRA)》2004,18(2):67-78
A methodology is developed for estimating temporally variable virus inactivation rate coefficients from experimental virus inactivation data. The methodology consists of a technique for slope estimation of normalized virus inactivation data in conjunction with a resampling parameter estimation procedure. The slope estimation technique is based on a relatively flexible geostatistical method known as universal kriging. Drift coefficients are obtained by nonlinear fitting of bootstrap samples and the corresponding confidence intervals are obtained by bootstrap percentiles. The proposed methodology yields more accurate time dependent virus inactivation rate coefficients than those estimated by fitting virus inactivation data to a first-order inactivation model. The methodology is successfully applied to a set of poliovirus batch inactivation data. Furthermore, the importance of accurate inactivation rate coefficient determination on virus transport in water saturated porous media is demonstrated with model simulations. 相似文献
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Soil denudation studies in urban environments are infrequent in the geomorphic literature. Here we describe the amount of soil erosion associated with pedestrian and bicycle pathways on an American university campus. The amount of soil denudation from thirty pedestrian/bicycle paths on the campus of the University of North Carolina was determined by morphometric measurements. Volumes denuded ranged from nearly 20 m3 to <0.2 m3 per site. Highest amounts were located at sites adjacent to a football stadium. Three types of paths were recognized, based on their utilization: paths running adjacent to existing sidewalks; paths cutting across lawns and through shrubbery from one sidewalk to another; and those formed by bicycles in order to avoid going up or down steps. 相似文献
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Vogler Daniel Walsh Stuart D. C. von Rohr Philipp Rudolf Saar Martin O. 《Acta Geotechnica》2020,15(8):2327-2340
Acta Geotechnica - Thermal spallation drilling is a contact-less means of borehole excavation that works by exposing a rock surface to a high-temperature jet flame. In this study, we investigate... 相似文献
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A new approach is presented to calculate the volume of oil in the underground at an oil spill site from fluid levels in monitoring wells. The approach includes the effects of hysteresis due to irregular pore geometry and to phase entrapment. It is possible to explain the drastic changes in the oil thickness in a monitoring well due to the decrease and increase in the groundwater table. A correct evaluation of the oil volume infiltrated underground from an oil spill and the effective control of remediation works can only be done by using the newly developed approach with a consideration of the dynamic changes in the groundwater table. 相似文献
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E. T. Vogler C. V. Chrysikopoulos 《Stochastic Environmental Research and Risk Assessment (SERRA)》2001,15(1):33-46
A two-dimensional numerical transport model is developed to determine the effect of aquifer anisotropy and heterogeneity
on mass transfer from a dense nonaqueous phase liquid (DNAPL) pool. The appropriate steady state groundwater flow equation
is solved implicitly whereas the equation describing the transport of a sorbing contaminant in a confined aquifer is solved
by the alternating direction implicit method. Statistical anisotropy in the aquifer is introduced by two-dimensional, random
log-normal hydraulic conductivity field realizations with different directional correlation lengths. Model simulations indicate
that DNAPL pool dissolution is enhanced by increasing the mean log-transformed hydraulic conductivity, groundwater flow velocity,
and/or anisotropy ratio. The variance of the log-transformed hydraulic conductivity distribution is shown to be inversely
proportional to the average mass transfer coefficient. 相似文献
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Michigan Basin oils from the Ordovician Trenton, Silurian Niagaran, and Devonian Dundee formations have been geochemically compared by GC, GC-MS, and carbon isotope mass spectrometry. One oil from each formation was selected for detailed analysis which included measurement of individual n-alkane δ13C values. The Ordovician and Devonian oils are strikingly similar to one another, yet clearly different from the Silurian oil. This pattern is unexpected because Ordovician and Devonian reservoirs are physically separated by the Silurian strata. From time-temperature considerations, the Devonian oil probably was formed in older strata and has migrated to its present location. Our analyses suggest a common source for the Devonian and Ordovician oils. 相似文献
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A three-dimensional numerical flow and contaminant transport model is developed to investigate the effect of variable hydraulic conductivity on average mass transfer coefficients associated with the dissolution of dense nonaqueous phase liquid (DNAPL) pools in heterogeneous, water-saturated subsurface formations. Randomly generated, three-dimensional hydraulic conductivity fields are used to represent a heterogeneous confined aquifer. Model simulations indicate that the average mass transfer coefficient is inversely proportional to the variance of the log-transformed hydraulic conductivity. A power law correlation relating the Sherwood number to the variance of the log-transformed hydraulic conductivity and appropriate Peclet numbers is developed. A reasonable fit between predicted and numerically determined mass transfer coefficients is observed. 相似文献
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Dr. Wolf Stefan Vogler 《International Journal of Earth Sciences》1984,73(1):175-206
A detailed petrofabric analysis leads to the following consequences at the Pillonet Klippe, a remnant of the Austroalpine Dent Blanche — Sesia Lanzo nappe system in the Western Alps. Two nappe forming events have to be distinguished: the first one marks the beginning, the second one the end of alpine tectonometamorphic evolution. While the first event is correlated to the early-alpine high-pressure low-temperature subduction zone metamorphism, the second event has no counterpart within the alpine metamorphic history. Post-Lepontine cold thrusts act at c. 250 °C cutting through early-alpine nappe boundaries and pile up a new sequence of nappes with different internal lithologies, structures and relics of late- and early-alpine metamorphism.Early-alpine deformation caused the penetrative first cleavage s1 and stretching lineation str1 and, subsequent two acts of folding D2 and D3 with axes parallel stretching. Nappe formation during this deformation started cold in a high crustal level and propagated into higher temperatures passing a boundary from clastic to plastic deformation. At the turning point of subduction c. 450 °C were reached, accompanied by static annealing. Until then glaucophane was stable.Late-alpine deformation caused different structures within different units of the latter klippe. They range from spectacular km-size 4th folds with NE-vergency in basement rocks to small 5th folds with NW-vergency in Mesozoic cover rocks. 5th folds postdate a static episode of Lepontine metamorphism with growth of albite porphyroblasts.Temperature had dropped markedly to less than 300 °C, when D6 thrust faults emerged cutting the klippen units out of their source regions. Thrust nappes develop giving rise to nappe movements over several km in the high structural level of Austroalpine nappes. Thus all fabrics — except D6 — are transported and are cut by these late and cold thrusts.
List of symbols D1-D3 1st to 3rd deformational act of early alpine age - D4-D5 4th and 5th deformational act of late alpine age - D6 post-Lepontine deformation - s1 str1 First cleavage and first stretching lineation of early alpine age - s2-3 B2-3 Cleavage planes and axes of 2nd–3rd early alpine folds - s4-5, B4-5 Cleavage planes and axes of 4th–5th late alpine folds - s6, L6 Thrust planes and lineations of post-Lepontine nappes - km, m, cm, mm kilometre, metre, centimetre, millimetre 相似文献
Zusammenfassung Die Pillonet-Klippe ist ein Überrest des Austroalpinen Dent Blanche — Sesia Lanzo Dekkensystems in den italienischen W-Alpen. Detaillierte gefügekundliche Untersuchungen haben dort zu folgenden Ergebnissen geführt:Man muß zwei deckenbildende Deformationsakte unterscheiden. Der erste steht am Anfang, der zweite am Ende der alpinen Deformations-Metamorphose-Geschichte. Decken bilden sich zum ersten Mal bei eoalpiner Subduktion unter Hochdruck-Niedrigtemperatur-Metamorphose. Ein zweites Mal nach Lepontiner Metamorphose, wenn kalte Thrusts bei ca. 250 °C den eoalpinen Deckenbau zerschneiden und zu neuen Decken mit unterschiedlichen Gesteinsbeständen, Strukturen und Relikten der früh- und spät-alpinen Metamorphosen stapeln. Zwischen diesen Deformationsakten läßt sich an der Pillonet-Klippe folgende Gefügeentwicklung beobachten:Während eoalpiner Deformation wird allen Gesteinen eine durchdringende erste alpine Schieferung s1 und Streckungsfaser str1 überprägt. Danach folgen zwei Akte der Faltung um Achsen parallel der Streckungsfaser: D2 und D3. Die Bildung von Decken während D1 beginnt kalt und klastisch in einem hohen Krustenstockwerk. Noch während D1 werden die Gesteine zunehmend geheizt und gelangen in Bereiche plastischer Deformation. Im Wendepunkt der Subduktion sind ca. 450 °C erreicht und eine statische Metamorphose schließt die eoalpine Geschichte ab. Glaukophan ist bis in die statische Temperung stabil.Während spätalpiner Deformation lassen sich in verschiedenen Einheiten der späteren Pillonet-Klippe unterschiedliche Gefügeentwicklungen beobachten. Die Variation reicht von km-großen, NE-vergenten 4. Falten in Altkristallin-Gesteinen bis zu m-großen, NWvergenten 5. Falten in der mesozoischen Bedeckung. Ein Akt statischer Lepontin-Metamorphose mit Albit-Blastese fällt zwischen D4 und D5.Nach deutlichem Temperaturabfall bis unter 300 °C werden die Klippen-Einheiten aus ihren Herkunftsgebieten gestanzt und gehen als Decken auf die Reise über mehrere km. Sie benutzen mylonitisierende Thrusts, entsprechend dem hohen Austroalpinen Stockwerk. Damit sind — bis auf die D6-Deckenbahnen — alle Gefüge der Pillonet-Klippe nicht dort erworben, sondern transportierte Gefüge, die von den späten, kalten Deckenbahnen geschnitten werden.
Résumé L'Ecaille du Pillonet est une résidu du système de nappes austro-alpines de la Dent blanche-Sesia Lanzo dans les Alpes occidentales italiennes. Des études structurales détaillées ont conduit aux résultats suivants:On doit distinguer dans la formation des nappes deux actes de déformation, le premier au commencement, le second à la fin de l'histoire de la déformation et du métamorphisme alpins. Des nappes se forment pour la première fois au cours de la subduction éoalpine dans des conditions de métamorphisme de haute pression-basse température; une deuxième fois après le métamorphisme lépontien, lorsque des charriages froids, à quelque 250 °C recoupent l'édifice de nappes éoalpines et échafaudent de nouvelles nappes avec des lithologies et structures différentes et des restes du métamorphisme alpin ancien et récent. Entre ces deux actes de la déformation, se sont développées les structures suivantes dans l'Ecaille du Pillonet;Pendant la déformation éoalpine, toutes les roches ont été marquées par une première schistosité pénétrative alpine s1 et une linéation str1. Viennent ensuite deux actes de plissement, D2 et D3 avec axes parallèles à la linéation. La formation des nappes pendant la déformation D1 commence dans des conditions froides et clastiques dans un étage crustal superficiel. Encore au cours de D1 les roches s'échauffant peu à peu et pénètrent dans le domaine de la déformation plastique. Au moment de la subduction, la température de 450 °C est atteinte et un métamorphisme statique cloture l'histoire éoalpine. Le glaucophane reste stable jusqu'alors.Pendant la dernière déformation, différent développements texturaux peuvent être observés dans chacune des entités de la future Ecaille du Pillonet. Ils varient depuis des plis de type 4, de dimension kilométrique, déversés vers le NE dans le cristallin ancien, jusqu'à des plis de type 5, de dimension métrique, déversés vers le NW dans le revêtement mésozoïque. Un métamorphisme lépontin statique avec blastèse albitique survient entre D4 et D5.Après une chute notable de la température jusque en dessous de 300 °C, les entités de l'Ecaillé se sont détachées de leur lieu d'origine et ont migré comme nappes sur plusieurs km. à la faveur de charriages mylonitisants correspondant au niveau austroalpin élevé. De sorte que toutes les textures, sauf celles qui sont liées au charriage D6, n'ont pas été acquises sur place, mais ont été transportées à froid par le dernier charriage.
. : . , . . , ( 250 °) . : S1 str1. D2 D3. D1 , . 450 ° . . . 4- 5- . D4 D5. 300 ° . , . . . , D6, , .
List of symbols D1-D3 1st to 3rd deformational act of early alpine age - D4-D5 4th and 5th deformational act of late alpine age - D6 post-Lepontine deformation - s1 str1 First cleavage and first stretching lineation of early alpine age - s2-3 B2-3 Cleavage planes and axes of 2nd–3rd early alpine folds - s4-5, B4-5 Cleavage planes and axes of 4th–5th late alpine folds - s6, L6 Thrust planes and lineations of post-Lepontine nappes - km, m, cm, mm kilometre, metre, centimetre, millimetre 相似文献