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11.
Falk Händel Gaisheng Liu Johann Fank Franz Friedl Rudolf Liedl Peter Dietrich 《Hydrogeology Journal》2016,24(8):2079-2091
An approach to establish the recharge component of managed aquifer recharge (MAR) has recently been proposed that uses small-diameter shallow wells installed using relatively inexpensive drilling methods such as direct push. As part of further development of that approach, a generalized procedure is presented for a technical and economic assessment of the approach’s potential in comparison to other systems. Following this procedure, the use of small-diameter wells was evaluated both experimentally and numerically for a site located in southern Styria, Austria. MAR is currently done at the site using a horizontal pipe infiltration system, and system expansion has been proposed with a target rate of 12 l/s using small-diameter wells as one possible option. A short-duration single-well field recharge experiment (recharge rate 1.3–3.5 l/s) was performed (recharge by gravity only). Numerical modeling of the injection test was used to estimate hydraulic conductivity (K). Quasi-steady-state, single-well recharge simulations for different locations, as well as a long-term transient simulation, were performed using the K value calibrated from the field injection test. Results indicate that a recharge capacity of 4.1 l/s was achievable with a maximum head rise of 0.2 m at the injection well. Finally, simulations were performed for three different well fields (4, 6 and 8 wells, respectively) designed to infiltrate a target rate of 12 l/s. The experimental and numerical assessments, supported by a cost analysis of the small-diameter wells, indicate that the small-diameter wells are a viable, cost-effective recharge approach at this and other similar sites. 相似文献
12.
Nazli Yonca Aydin H. Sebnem Duzgun Friedemann Wenzel Hans Rudolf Heinimann 《Natural Hazards》2018,91(1):37-68
Transportation networks daily provide accessibility and crucial services to societies. However, they must also maintain an acceptable level of service to critical infrastructures in the case of disruptions, especially during natural disasters. We have developed a method for assessing the resilience of transportation network topology when exposed to environmental hazards. This approach integrates graph theory with stress testing methodology and involves five basic steps: (1) establishment of a scenario set that covers a range of seismic damage potential in the network, (2) assessment of resilience using various graph-based metrics, (3) topology-based simulations, (4) evaluation of changes in graph-based metrics, and (5) examination of resilience in terms of spatial distribution of critical nodes and the entire network topology. Our case study was from the city of Kathmandu in Nepal, where the earthquake on April 25, 2015, followed by a major aftershock on May 12, 2015, led to numerous casualties and caused significant damage. Therefore, it is a good example for demonstrating and validating the developed methodology. The results presented here indicate that the proposed approach is quite efficient and accurate in assisting stakeholders when evaluating the resilience of transportation networks based on their topology. 相似文献
13.
Martin Gast Wolfgang Schaaf Joerg Scherzer Rudolf Wilden Bernd U. Schneider Reinhard F. Hüttl 《Journal of Geochemical Exploration》2001,73(2):196
To analyze the development of pine ecosystems on lignite and pyrite containing mine soils, four pine stands with ages of 3–35 years were investigated in a chronosequence approach. Bulk precipitation, throughfall and soil solution in depths of 20, 40, 70 and 100 cm were studied over a three-year period to determine element fluxes in these forest ecosystems on extreme acidic and saline soils.Element budgets are controlled by the processes induced by pyrite oxidation such as intensive weathering of primary minerals, precipitation and leaching of secondary phases.Despite low water fluxes, element outputs can reach extraordinary high values due to very high concentrations in the soil solution. Although element outputs decrease drastically with stand age, respectively, site age, they exceed those of comparable pine stands on non-mine sites. Nitrogen release from the lignite fraction represents a special characteristic of the examined substrates. Nitrogen losses beneath the rooted zone can be 34 kg N ha−1 yr−1 in 100 cm depth. Element input and output in the examined ecosystems are far from balance. Closed cycling of nutrients seems to be recognizable in the case of potassium. 相似文献
14.
15.
Rudolf Penndorf 《Meteorology and Atmospheric Physics》1963,13(3-4):481-484
16.
Zusammenfassung In der geosynklinalen Vorgeschichte mancher Kettengebirge gibt es zwei Phasen mit verschiedener paläogeographischer Konfiguration: 1. mit Dehnungstektonik, 2. mit Kompressionstektonik. Der Höhepunkt der vororogenen magmatischen Tätigkeit fällt in eine Zwischenphase mit geringerem submarinem Relief.Kurzfassung eines am 12. März 1960 vor der Geologischen Vereinigung gehaltenen Vortrages. Eine ausführliche Arbeit über die Geosynklinalentwicklung der Westalpen (mit umfangreichem Literaturverzeichnis) erschien im Bull. Geol. Soc. America, Juni 1960, unter dem Titel Paleotectonic Evolution of the Central and Western Alps. 相似文献
17.
Rudolf A. Gees 《International Journal of Earth Sciences》1972,61(1):322-331
Zusammenfassung Die Psephit-Diabas-Miktite wurden durch Infiltration von Diabas in die Porenräume der Psephite gebildet. Die Taveyannaz-Andesite wurden längs der Grenzzone zwischen der helvetischen Miogeosynklinale und der penninischen Eugeosynklinale gefördert.
Rudite-diabase mictites were formed by infiltration of diabase into the pore spaces of the rudites. The Taveyannaz andesites were emplaced along the boundary between the Helvetic miogeosyncline and the Pennine eugeosyncline.
Résumé Les mictites pséphite-diabasiques résultent de l'infiltration de diabase dans les pores des pséphites. Les andésites du type Taveyanne s'infiltrèrent le long de la limite entre le miogéosynclinal helvétique et l'eugéosynclinal pennique.
- . Taveyannaz .相似文献
18.
Prof. Dr. Rudolf Trümpy 《International Journal of Earth Sciences》1972,61(3):961-964
Zusammenfassung Die alpine Krustenverkürzung (300–400 km oder mehr im Profil der Westschweiz, 400–500 km oder mehr im Profil der Ostschweiz) erfolgte in diskreten orogenen Phasen, welche durch Zeiten langsamerer Bewegung oder eigentlicher Remission getrennt waren. Während der wichtigsten Phase, an der Eozän-Oligozän-Wende, betrug die Relativgeschwindigkeit der nördlichen Platte und der südlichen Kleinplatte einige cm/a.
Crustal shortening in the Central Alps (300–400 km or more in western Switzerland, 400–500 km or more in eastern Switzerland) occurrend in discrete orogenic phases, separated by times of slower movement or of complete stop. During the most important phase, at the turn from the Eocene to the Oligocene, the rate of relative movement of the northern plate and the southern microplate was of the order of several cm/y.
Résumé Le raccourissement de la croûte dans les Alpes Centrales (300–400 km ou davantage en Suisse occidentale, 400–500 km ou davantage en Suisse orientale) se fit par phases orogéniques défines, séparées par des intervalles à mouvement plus lent ou même à arrêt total. Pendant la phase principale, à la fin de l'Eocène ou au début de l'Oligocène, la vitesse relative de la plaque septentrionale et de la microplaque méridionale était de l'ordre de plusieurs cm/a.
(300–400 , , 400–500 , ) , , . , - , /.相似文献
19.
20.
The supersaturation of neon in southeastern Pacific deep sea water is unexpectedly high, 6.6% on the average, while surface waters have values about a factor of two lower. A comparison of neon and argon concentrations indicates the presence of injected air in the deep water. The results from surface samples cannot be reconciled with air injection. 相似文献