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31.
Prof. Dr. Matthias Matschinski 《Pure and Applied Geophysics》1955,32(1):19-30
Zusammenfassung der mathematischen Ergebnisse Die von uns erhaltenen annäherndD' Alembert'schen Lösungsformen der Wellengleichung (1) sind mit den Formeln (11), (14) und (25) dargestellt; die Bedingungen für ihre Existenz sind im Hauptsatz gegeben.
Summary Case of two reflected waves in Seismology and in general Mechanics. Four types of waves near to a surface. The general properties of the concept «wave». Thermic and geometric extinction of a wave. Conditions a) that an aggregate of waves has the properties of a wave, and b) that the so formed aggregate has no more these properties. A new case of solution near to the type ofD' Alembert; some applications. Interference of two waves and impossibility of such interference of two ensembles of waves, in the general case.
Resumé Deux ondes réflechies en Séismologie et en Mécanique générale. Quatro types des ondes près d'une surface. Les propriétés générales de la notion d' «onde». Amortissement thermique et géométrique d'une onde. Les conditions où un agrégat des ondes fornie une onde et où cet agrégat n'est pas une onde. Un nouvel cas de la solution de l'équation d'ondes proche à la solution deD' Alembert. Quelques applications. L'interférence de deux ondes et l'impossibilité de l'interference dans le cas général de deux ensembles des ondes.相似文献
32.
33.
Frank Peeters Urs Beyerle Matthias S. Brennwald 《Geochimica et cosmochimica acta》2004,68(6):1437-1438
34.
Pleistocene/Holocene climate change, re-establishment of fluvial drainage network and increase in relief in the Swiss Alps 总被引:1,自引:0,他引:1
ABSTRACT Data are presented about modern sediment discharge of the Swiss rivers and related to the size of catchments. The information reveals that the Central Alps have experienced denudation rates of ≈0.15 mm yr−1 in the foreland, and ≈0.5 mm yr−1 in the Alpine core. Mapping, however, indicates that modern erosion only affects 30–50% of the Alpine surface, and that fluvial and associated hillslope processes have focused erosion in 50–200-m-deep valleys. These valleys are incised into the glacial surface. If this limited spatial extent of erosion is considered, then effective erosion rates are significantly higher than average denudation rates. These effective rates equal or locally exceed modern rates of rock uplift. This implies that the modification of erosional processes related to the Pleistocene/Holocene climate change has resulted in an increase in the relief at a local scale. At a drainage basin scale, however, the relief appears not to change at present. 相似文献
35.
Jean-Pierre Berger Bettina Reichenbacher Damien Becker Matthias Grimm Kirsten Grimm Laurent Picot Andrea Storni Claudius Pirkenseer Andreas Schaefer 《International Journal of Earth Sciences》2005,94(4):711-731
We present a general stratigraphic synthesis for the Upper Rhine Graben (URG) and the Swiss Molasse Basin (SMB) from Eocene to Pliocene times. The stratigraphic data were compiled both from literature and from research carried out by the authors during the past 6 years ; an index of the stratigraphically most important localitites is provided. We distinguish 14 geographical areas from the Helvetic domain in the South to the Hanau Basin in the North. For each geographical area, we give a synthesis of the biostratigraphy, lithofacies, and chronostratigraphic ranges. The relationships between this stratigraphic record and the global sea-level changes are generally disturbed by the geodynamic (e.g., subsidence) evolution of the basins. However, global sea-level changes probably affected the dynamic of transgression–regression in the URG (e.g., Middle Pechelbronn Beds and Serie Grise corresponding with sea-level rise between Ru1/Ru2 and Ru2/Ru3 sequences, respectively) as well as in the Molasse basin (regression of the UMM corresponding with the sea-level drop at the Ch1 sequence). The URGENT-project (Upper Rhine Graben evolution and neotectonics) provided an unique opportunity to carry out and present this synthesis. Discussions with scientists addressing sedimentology, tectonics, geophysics and geochemistry permitted the comparison of the sedimentary history and stratigraphy of the basin with processes controlling its geodynamic evolution. Data presented here back up the palaeogeographic reconstructions presented in a companion paper by the same authors (see Berger et al. in Int J Earth Sci 2005). 相似文献
36.
Manfred Frechen Dietrich Ellwanger Matthias Hinderer Jörg Lämmermann-Barthel Inge Neeb Astrid Techmer 《International Journal of Earth Sciences》2010,99(8):1955-1974
During the Pleistocene, the Rhine glacier system acted as a major south–north erosion and transport medium from the Swiss
Alps into the Upper Rhine Graben, which has been the main sediment sink forming low angle debris fans. Only some aggradation
resulted in the formation of terraces. Optically stimulated luminescence (OSL) and radiocarbon dating have been applied to
set up a more reliable chronological frame of Late Pleistocene and Holocene fluvial activity in the western Hochrhein Valley
and in the southern part of the Upper Rhine Graben. The stratigraphically oldest deposits exposed, a braided-river facies,
yielded OSL age estimates ranging from 59.6 ± 6.2 to 33.1 ± 3.0 ka. The data set does not enable to distinguish between a
linear age increase triggered by a continuous autocyclical aggradation or two (or more) age clusters, for example around 35 ka
and around 55 ka, triggered by climate change, including stadial and interstadial periods (sensu Dansgaard–Oeschger cycles).
The braided river facies is discontinuously (hiatus) covered by coarse-grained gravel-rich sediments deposited most likely
during a single event or short-time period of major melt water discharge postdating the Last Glacial Maximum. OSL age estimates
of fluvial and aeolian sediments from the above coarse-grained sediment layer are between 16.4 ± 0.8 and 10.6 ± 0.5 ka, and
make a correlation with the Late Glacial period very likely. The youngest fluvial aggradation period correlates to the beginning
of the Little Ice Age, as confirmed by OSL and radiocarbon ages. 相似文献
37.
Nico-Alexander Urbanski Malte Vöge Ralf Seyfried Lars Rüpke Tanja Petersen Till Hanebuth Matthias Hort 《International Journal of Earth Sciences》2002,91(4):712-722
The intention of our study was to gain new insight into the complex interplay between different types of eruption of the Stromboli volcano by combining detailed field observation with different geophysical methods. We recorded more than 600 eruptions by use of continuous Doppler radar measurements. We detected the onset of the seismic precursor and the beginning of the visible eruption by use of seismic and infrared data. Two soil samples per day were used to monitor the effect of humidity on the eruptive style. We mapped the crater region as a reference base for the long-term morphological changes of the active region and for the exact positions of our measurement systems. Two distinct types of eruption were distinguished from each other on the basis of seismic and radar data - short, wide-angle Strombolian explosions and pulsating, sharp angle fountain-like eruptions. Data and visual observations imply that weather conditions significantly effect volcanic activity. We also interpret the intensification of eruptive activity during our field study as replenishment of the reservoir with a new batch of magma in late September 2000. 相似文献
38.
Prof. Dr. Matthias Kuhle 《GeoJournal》1989,18(4):441-450
A reductionistic concept is being pursued in the 125 000 geomorphological mapping of the Federal Republic of Germany. Complex landscape elements with a base length greater than 100 m are broken down into partial elements and re-interpreted in terms of quantificational or abstractly defined, theoretically neutral map symbols. The genetic aspect is expressed by areal colouring. In this way it aims to achieve an interdisciplinary utilization of such information. This reduction has proved to be too drastic insofar as it gives rise to irretrievable loss of information. The claim that use-oriented, ecologically relevant information would be derivable from the GMM-25 has not been substantiated. As ecologically justifiable evaluation must also consider as its most fundamental indicators the quality and distribution of biotopes. These are not even rudimentarily included in the GMM-25. The uncontextualized blending of information units which only make sense in heterogeneous contexts to produce a single map is antithetical to the principle of subject related selection of relevant characteristics and prevents comprehension of the systematic relationships.The underlying concept of the GMM-25, derived from an uncritical incorporation of physico-mathematical total predictability principles, leads to an irreversible renunciation of the necessarily complex constituents of a high geomorphological level of integration. 相似文献
39.
István Gábor Hatvani Norbert Magyar Matthias Zessner József Kovács Alfred Paul Blaschke 《Hydrogeology Journal》2014,22(4):779-794
Water protection is one of the most important goals in environmental protection. The Clean Water Act in the USA and the Water Framework Directive (WFD) in Europe are the legal frameworks to facilitate the achievement of this goal. The question is raised of whether more information can be extracted from WFD-related groundwater data. To answer it, a methodology has been developed that is easy to use and could be implemented into official practice. A case study is presented in which the groundwater data of a sodic area in Austria (Seewinkel) is assessed. Eighteen parameters in groundwater sampled from 23 wells (1991–2011) were analyzed. With basic statistics, trend-, cluster-, Wilks’ λ and spatial sampling density analysis, local phosphorus and boron phenomena were described, along with the determining role of sulphate, groundwater flow, and the oxygen gradient in the area. As a final step, the spatial sampling density was determined. Regarding the current set of parameters, all the sampling sites are necessary and only in the case of certain parameters (Ca2+, Mg2+, K+, NO3 ?, pH) could one sampling site be abandoned. The methodology applied brings a new perspective to exploring groundwater data collected according to the requirements of the WFD. 相似文献
40.
Matthias Lendholt 《Earth Science Informatics》2011,4(1):7-16
This paper presents a novel approach for early warning systems to transform the spatial reference of dispersion models into
addressable administrative units enabling an intelligible warning message reception and spatial awareness. The spatial reference
along the entire information chain from sensor measurements via dispersion model to warning dissemination is discussed. Core
concept behind this approach is the application of the Egenhofer-Model for analysis of binary topologic relations. It is used
to identify topologic relations between dispersion model forecasts and administrative units. The result set of intersection
matrices defines the relations that are counted for area classification with hazard specific parameters. Following the design
for a generic and hazard-independent web service based on Open Geospatial Consortium (OGC) standards is presented in combination
with results of the reference implementation. 相似文献