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71.
Malinda L. Kent‐Corson Andreas Mulch Stephan A. Graham Alan R. Carroll Bradley D. Ritts C. Page Chamberlain 《Basin Research》2010,22(6):829-845
Early Cenozoic terrestrial deposits in the western United States represent well‐preserved archives of climatic and tectonic processes that together shaped the Earth's surface during the demise of a large continental plateau. This study examines a Cenozoic terrestrial sedimentary sequence in the central part of the Cordilleran orogen (Montana) using sedimentologic and geochemical techniques. At ~49 Ma, we observe rapid major shifts in oxygen, carbon and strontium isotope records that are too large to directly reflect changes in meteoric water composition due to simple orographic rainout. The transition to low‐δ18O values in pedogenic carbonate in concert with changes in the composition of clastic material at ~49 Ma points to the input of evolved meteoric water to the hydrological cycle due to a change in the source of waters reaching Cordilleran intermontane regions in southwestern Montana. This drainage reorganization coincides with the initiation of magmatism and extension to the west in what is now Montana and Idaho. The sedimentological record shows evidence that depositional gradients increased in the study area ~46 Ma, ~3 Myr after the drainage reorganization occurred. This interval is most likely the time it took for extensional deformation to propagate to the study area itself. Evidence of freshening events in Laramide Basins to the southeast suggests that this drainage reorganization diverted waters to progressively fill these basins and highlights the impact of post‐plateau extension‐related landscape reorganization on river networks and lake dynamics. This study also emphasizes the importance of using multiple tools in deciphering topographic history through the study of terrestrial basin deposits, in that interpretation based on any single method employed would have compromised our ability to successfully identify the regional evolution of topography and drainage networks. 相似文献
72.
Hartmut H. Hellmer Monika Rhein Günther Heinemann Janna Abalichin Wafa Abouchami Oliver Baars Ulrich Cubasch Klaus Dethloff Lars Ebner Eberhard Fahrbach Martin Frank Gereon Gollan Richard J. Greatbatch Jens Grieger Vladimir M. Gryanik Micha Gryschka Judith Hauck Mario Hoppema Oliver Huhn Torsten Kanzow Boris P. Koch Gert König-Langlo Ulrike Langematz Gregor C. Leckebusch Christof Lüpkes Stephan Paul Annette Rinke Bjoern Rost Michiel Rutgers van der Loeff Michael Schröder Gunther Seckmeyer Torben Stichel Volker Strass Ralph Timmermann Scarlett Trimborn Uwe Ulbrich Celia Venchiarutti Ulrike Wacker Sascha Willmes Dieter Wolf-Gladrow 《Ocean Dynamics》2016,66(11):1379-1413
73.
74.
The Open-source Project for a Network Data Access Protocol (OPeNDAP) software framework has evolved over the last 10 years to become a robust, high performance, service oriented architecture for the access and transport of scientific data from a broad variety of disciplines, over the Internet. Starting with version 4.0 of the server release, Hyrax, has at its core, the Back-End Server (BES). The BES offers ease of programming, extensibility and reliability allowing added functionality especially related to high-performance data Grids, that goes beyond its original goal of distributed data access. We present the fundamentals of the BES server as a component based architecture, as well as our experiences using the BES to distribute data processing in Grid-oriented intensive parallel computational tasks. 相似文献
75.
Stephan Winter Zhang-Cai Yin 《International journal of geographical information science》2013,27(9):1349-1365
This article studies probabilistic time geography for space–time prisms, that is, for situations where observers know the location of an agent at one time and then again at another time. In the intervening period, the agent would have moved freely, according to its time budget. The article demonstrates that the probability of finding the agent somewhere in the space–time prism is not equally distributed, so any attempt of a quantitative time geographic analysis must consider the actual probability distribution. This article develops, implements, and demonstrates this distribution. A preceding article introduced probabilistic time geography for space–time cones. With cones and prisms, the elementary space–time volumes of time geography are provided. 相似文献
76.
A series of 112 earthquakes was recorded between October 2005 and August 2007 during the excavation of the MFS Faido, the southernmost access point of the new Gotthard Base Tunnel. Earthquakes were recorded at a dense network of 11 stations, including 2 stations in the tunnel. Local magnitudes computed from Wood?CAnderson-filtered horizontal component seismograms ranged from ?1.0 to 2.4; the largest earthquake was strongly felt at the surface and caused considerable damage in the tunnel. Hypocenter locations obtained routinely using a regional 3-D P-wave velocity model and a constant Vp/Vs ratio 1.71 were about 2?km below the tunnel. The use of seismic velocities calibrated from a shot in the tunnel revealed that routinely obtained hypocenter locations were systematically biased to greater depth and are now relocated to be on the tunnel level. Relocation of the shot using these calibrated velocities yields a location accuracy of 25?m in longitude, 70?m in latitude, and 250?m in focal depth. Double-difference relative relocations of two clusters with highly similar waveforms showed a NW?CSE striking trend that is consistent with the strike of mapped faults in the MFS Faido. Source dimensions computed using the quasidynamic model of Madariaga (Bull Seismo Soc Am 66(3):639?C666, 1976) range from 50 to 170?m. Overlapping source dimensions for earthquakes within the two main clusters suggests that the same fault patch was ruptured repeatedly. The observed seismicity was likely caused by stress redistribution due to the excavation work in the MFS Faido. 相似文献
77.
Klaus-G. Hinzen Stephan Schreiber Claus Fleischer Sharon K. Reamer Isabel Wiosna 《Journal of Seismology》2013,17(2):399-424
The causes of damage observed in archeological records or preserved monuments are often difficult to be determined unequivocally, particularly when the possibility of secondary earthquake damage exists. Such secondary damage has been previously proposed for the Roman Praetorium, the governor’s palace in the center of Cologne. Ongoing excavations since 2007 revealed additional damage. The existing ground that has been uncovered and documented extends the affected area to 175?×?180 m. We present a comprehensive virtual model of the excavation area based on 200 3D laserscans together with a systematic analysis of the damage patterns and an improved model of the terrain during Roman/Medieval times including geotechnical parameters of the subsurface. Five locations with different damage patterns, including a Roman sewer, the octagonal central part of the Praetorium, a section with strongly inclined massive walls, a 13 m deep deformed well, a collapsed hypocaust, and damages in the Medieval mikveh are analyzed in detail. We use site-specific synthetic strong ground motion seismograms to test the possibility of earthquake-induced ground failures as a cause for the observed damage. This subsurface model is also used to test the possibility of hydraulically-induced damages by seepage and erosion of fine-grained material from stray sand. Heavy rainstorms can induce a direct stream of surface water through the fine sand layers to the ground water table. Simulated ground motion for assumed worst-case earthquake scenarios do not provoke slope instability at the level necessary to explain the structural damages. 相似文献
78.
Greene Brian R. Kral Stephan T. Chilson Phillip B. Reuder Joachim 《Boundary-Layer Meteorology》2022,183(3):321-353
Boundary-Layer Meteorology - We explore the potential of a new method for the estimation of profiles of turbulence statistics in the stable boundary layer (SBL). By applying gradient-based scaling... 相似文献
79.
Adrian Costea Quoc T. Le Gia Ernst P. Stephan Thanh Tran 《Studia Geophysica et Geodaetica》2011,55(3):465-477
We consider the exterior Neumann problem of the Laplacian with boundary condition on spheroids. We propose to use spherical
radial basis functions in the solution of the boundary integral equation arising from the Dirichlet-to-Neumann map. Our meshless
approach with radial basis functions is particularly suitable for handling scattered satellite data. We also propose a preconditioning
technique based on an overlapping domain decomposition method to deal with ill-conditioned matrices arising from the approximation
problem. 相似文献
80.
Sabine Geiß Nicole Lettmann Aurélien Rey Herbert Lepper Birgit Körner Silvio Mais Theodor Prey Bettina Hilger Moana Engelke Stephan Lebertz Claudine Chatellier George Sawal Dirk Löffler Tom Schillings 《洁净——土壤、空气、水》2011,39(6):537-542
A first preliminary interlaboratory trial was planned to prepare ISO/DIS 12010: Water quality – determination of short chain polychlorinated alkanes (SCCP) in water – method using GC/MS and electron capture negative ionisation (ECNI). The task was to determine the sum of short chain polychlorinated n‐alkanes with carbon chain lengths of C10–C13 and a chlorine content between 49 and 67% in water by GC‐ECNI‐MS and quantification by multiple linear regression described in ISO/DIS 12010 as the compulsory method. Distributed samples were obtained from a real water extract spiked with a target concentration of 0.4 µg/mL sum of SCCP, i.e. the environmental quality target level according to the Water Framework Directive. The interlaboratory trial included the calibration, a column chromatographic clean up, a concentration step and an integration of chromatographic unresolved humps as well as the quantification with multiple linear regression. Reproducibility standard deviations between 21.5 and 22.9% were achieved by 17 participating laboratories from four countries. The method outlined no significant difference of the results between the standard solution and a real water matrix extract. On the basis of this succeeded preliminary interlaboratory trial the final interlaboratory trial for validation of ISO 12010 was prepared in autumn 2010. 相似文献