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91.
Manfred Baer Nicolas Deichmann Jochen Braunmiller John Clinton Stephan Husen Donat Fäh Domenico Giardini Philipp Kästli Urs Kradolfer Stefan Wiemer 《Swiss Journal of Geoscience》2007,100(3):517-528
This report of the Swiss Seismological Service summarizes the seismic activity in Switzerland and surrounding regions during
2006. During this period, 572 earthquakes and 91 quarry blasts were detected and located in the region under consideration.
Of these earthquakes, two occurred in conjunction with the construction of the new Gotthard railway tunnel and 165 were induced
artificially by the stimulation of a proposed geothermal reservoir beneath the city of Basel. With 20 events with M
L
≥ 2.5, five of which were artificially induced, the seismic activity in the year 2006 was far below the average over the
previous 31 years. Nevertheless, six events were felt by the public, most prominently the strongest of the induced Basel events
(M
L
3.4), which caused some non-structural building damage. Noteworthy are also the two earthquakes near Cortaillod (M
L
3.2), on the shore of Lake Neuchatel, and in Val Mora (M
L
3.5), between the Engadin and Val Müstair, as well as the 42 aftershocks of the M
L
4.9 Vallorcine earthquake, between Martigny and Chamonix, of September 2005.
Editorial handling: Stefan Bucher 相似文献
92.
93.
Two colour laser ranging to artificial satellites is an attractivetechnique, which is capable to provide refraction corrected ranges without the need of an atmospheric model by measuring the dispersive delay of laser pulses of different wavelength. Although the required accuracy of the detection scheme is stringent, the technique has matured so far, that routine two colour observationsbecame feasible.The present paper describes a normal point procedure reducing two colour laser range observations with respect to the dispersive delay,exploiting the knowledge of satellite response signatures in conjunction with detector characteristics and the appropriate center of mass correction models.Moreover the dispersion model of the atmosphere is briefly reviewed, paying attention to the wavelength domains provided by modern twocolour ranging lasers, e.g., the Ti:SAP laser.Preliminary data is presented and compared to both, normal point data reduced with a standard procedure and zenith path equivalent meteorological parameters. 相似文献
94.
Mark L. Kram Stephen H. Lieberman Jerry Fee Arturo A. Keller 《Ground Water Monitoring & Remediation》2001,21(1):67-76
The site characterization and analysis cone penetrometer system (SCAPS), equipped with realtime fluorophore detection capabilities, was used to delineate subsurface contaminant releases in an area where plating shop waste was temporarily stored. Records indicated that various nonaqueous phase liquids (NAPLs) were released at the site. The investigators advanced the SCAPS laser-induced fluorescence (LIF) sensor to depths beneath the water table of the principal water-bearing zone. The water table was located approximately 6 feet (1.8 m) below ground surface (bgs) across the site. Fluorescence, attributed to fuel compounds commingled with chlorinated solvents, was observed at depths ranging from 4.0 to 11.5 feet (1.2 to 3.5 m) bgs. Fluorescence, attributed to naturally occurring organic materials (by process of elimination and spectral characteristics) commingled with chlorinated solvent constituents, was observed at depths ranging from approximately 13 to 40 feet (4.0 to 12.2 m) bgs. Fluorescence responses from compounds confirmed to be commingled with chlorinated solvents indicates that the SCAPS fluorophore detection system is capable of indirectly delineating vadose zone and subaqueous chlorinated solvents and other dense nonaqueous phase liquids (DNAPLs) at contaminant release sites. This confirmation effort represents the first documented account of the successful application of LIF to identify a mixed DNAPL/LNAPL source zone. 相似文献
95.
A new method to estimate strain and competence contrast from natural fold shapes is developed and verified by analogue and numerical experiments. Strain is estimated relative to the nucleation amplitude, AN, which is the fold amplitude when the amplification velocities caused by kinematic layer thickening and dynamic folding are identical. AN is defined as the initial amplitude corresponding to zero strain because folding at amplitudes smaller than AN is dominantly by kinematic layer thickening. For amplitudes larger than AN, estimates of strain and competence contrast are contoured in thickness-to-wavelength (H/λ) and amplitude-to-wavelength (A/λ) space. These quantities can be measured for any observed fold shape. Contour maps are constructed using existing linear theories of folding, a new nonlinear theory of folding and numerical simulations, all for single-layer folding. The method represents a significant improvement to the arc length method. The strain estimation method is applied to folds in viscous (Newtonian), power-law (non-Newtonian) and viscoelastic layers. Also, strain partitioning in fold trains is investigated. Strain partitioning refers to the difference in strain accommodated by individual folds in the fold train and by the whole fold train. Fold trains within layers exhibiting viscous and viscoelastic rheology show different characteristic strain partitioning patterns. Strain partitioning patterns of natural fold trains can be used to assess the rheological behaviour during fold initiation. 相似文献
96.
97.
Stefan Bauer-Wolf 《GeoJournal》1992,27(1):84-84
Alpen: Verkehr und fremdenverkehr 相似文献
98.
Zusammenfassung Bleiglanzproben aus verschiedenen Lagerstätten der Sierra de Cartagena wurden auf ihre Blei-Isotopen-Verhältnisse untersucht. Auffallend ist deren völlig identische Pb-Isotopen-Zusammensetzung, aus der sich nach dem Houtermans-Modell ein Modell-Alter von 30 Millionen Jahren errechnen läßt. Die Blei-Mineralisation im Erzdistrikt von Cartagena steht daher in einem sicheren Zusammenhang mit der Tätigkeit jungtertiärer subvulkanischer Magmenherde. Das Alter der Andesite wurde mittels Rb/Sr-Methode an einem Biotit des Atalaya-Andesites mit 44±27 m.y. bestimmt. Dieser Wert stimmt sehr gut mit einer Altersbestimmung an einem leukogranitischen Gang aus der Sierra Cabrera überein (50±3 m.y.). Die Ergebnisse der Spurenelement-bestimmung an Bleiglanzproben werden im Zusammenhang mit schon früher mitgeteilten Schwefel-Isotopen-Daten diskutiert.
Lead isotope ratios have been determined in galena samples from the Sierra de Cartagena (Spain). The range of the Pb-isotopes is extremely narrow within the ore district, which contains different types of ore deposits. The age of the galena bearing ore deposits has been determined by using the Houtermansmodel: 30 million years. The lead minertalisation in the district therefore may be linked to the subvolcanic activity of Tertiary age. Ascribing the mineralisation to three volcanic episodes of Palaeozoic, Miocene and Pliocene ages and two periodes of supergene processes is not possible. Rb/Sr ratios have been determined in a biotite sample from the Atalaya andesite. The mica age is 44±27 m.y. which is in closest agreement with the age given for rocks in the Sierra Cabrera (50±3 m.y.). The results of trace element analyses are discussed in connection with previously studied sulphur isotope composition.相似文献
99.
Occurrence and field relations of an extensive ignimbrite sheet near Afyon in Central Anatolia are described. These rhyolitic ignimbrites are part of the important Neogene volcanic activity in Turkey and belong to the alignment of volcanic complexes along the inner border of the Taurian ranges. In close stratigraphical connection and in the same tectonic position as the rhyolites there occurs an assemblage of high-potassic, intermediate to basic volcanic rocks (alkali trachytes, mela-trachytes, latites and leucite-bearing rocks). Petrological and magmatological considerations led to the conclusion that the rhyolites and the potassic series, in spite of the close geological connection, are not related by processes of magmatic differentiation. Arguments in favour of an anatectic origin of the rhyolitic melt are presented. The occurrence of garnet and allanite as accessory minerals and as inclusions in the salic minerals of the ignimbrite are interpreted as relictic witnesses of a sialic parent rock. However, the trace elements, especially high Rb connected with low Sr, Ba and Zr and K/Rb ratios below 100 give a pattern generally explained by strong fractionation processes. 相似文献
100.
J. Keller 《Bulletin of Volcanology》1969,33(3):942-959
Rhyolitic pumice deposits on some East Aegean Islands are the remnants of a tuff sheet which covered formerly more than 2500 km2. The rhyolites originated by melting of granitic crustal rocks. The petrological properties leading to this conclusion are as follows: -mineralogical composition of the pumice being 60 wt % of glass and 40 % of relictic granitic minerals (quartz, plagioclase, potash feldspar, biotite) in «phenocrysts» up to 1 cm Ø. -phenomena of strong corrosion, resorption and melting of all light colored «phenocrysts» in the rhyolitic pumice. -mineralogical and chemical identity between pumice and granitic xenolites found in great quantity in the pumice tuff. -structurally transitional types between pumice and the granites in different state of melting. -eutectic composition of the pumice glass for a pressure of 2 kb. 相似文献