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411.
Nemati Fatemeh Grilli Stephan T. Ioualalen Mansour Boschetti Laurie Larroque Christophe Trevisan Jenny 《Natural Hazards》2019,96(2):553-586
Natural Hazards - The French Riviera is a densely populated and touristic coast. It is also one of the most seismically active areas of the Western Mediterranean. This is evidenced by the Mw... 相似文献
412.
Lake Lisan, the lake that filled the Jordan graben during the Last Glacial, left behind a well developed sequence of erosional and depositional shore terraces in the south east of the current Dead Sea. These terraces record a series of stillstands that were caused by small transgressions within an overall trend of falling lake levels. The terraces were observed in places where they had not been identified previously. The morphology of the terraces was investigated in six cross-sections using differential GPS altimetry. The levels of the terraces range between − 370 and − 148 m a.s.l. The high stand of Lake Lisan at − 148 m correlates well with the high level of − 150 m reported by Bowman and Gross [Bowman, D., Gross, T., 1992. The highest stand of Lake Lisan: ~ 150 meters below MSL. Israel Journal of Earth-Science 41, 233–237.] along the western coast of Lake Lisan. The lake terraces are horizontal, elongated and tectonically undisturbed, and have a sub-horizontal foreshore (tread) with an average slope of 8.2° and steep backshore cliff (riser) with an average slope of 17.7°. The six cross-sections show a good altitudinal correlation between their terraces. Moreover, the terraces appear in undisturbed continuity on the aerial photos. These morphological characteristics demonstrate that the retreat of the lake was a result of substantial climatic changes, not of tectonic subsidence.In-situ stromatolites were found on most of the terraces, reflecting a shallow water environment and emphasizing that these terraces are recessional. Well-developed desert varnish and Tafoni observed on blocks sitting on the terrace surfaces imply a long period of exposure and a low rate of post lacustrine erosion. The formation of Lisan terraces is constrained mainly by coastal slope, water depth and underlying lithology. The morphological analysis of these terraces allows identification of two kinds of pseudo-terraces, which were formed as a result of tread or riser destruction.U/Th and OSL dating allowed the dating of three events within the lake level curve more precisely. The high level of − 148 m occurred at 30.5 ± 0.22 ka BP, consistent with the Heinrich Event 3 and Dansgaard–Oeschger stadial 5, the coldest period in the NGRIP Greenland Ice Core record. The next lower terrace at − 154 m was formed at 22.9 ka BP ± 0.29 and corresponds to the stadial 2C, the final phase of the Last High Glacial. The correlation between the Lisan high stands and climatic stadials suggests that Northern-Hemispheric cold periods led to periods with a more positive water balance in the Near East. At ~ 10 ± 0.8 ka BP Lake Lisan experienced a sharp drop to − 200 m followed by a transgression between 9.5 to 7 ka BP. 相似文献
413.
414.
Exsolution and coarsening in Fe-free clinopyroxene of composition En45.1Di54.9 was studied at temperatures of 1300, 1200, and 1100°C, and annealing times between 10 min and 4320 h. Based on the wavelength of the exsolution lamellae, the exsolution process can be divided into exsolution sensu stricto and coarsening. During exsolution sensu stricto, the average wavelength of the “001” and “100” lamellae remains constant in contrast to the subsequent coarsening process. A progressive development of the microstructure is observed before coarsening which includes formation of island-like regions of dark contrast without phase separation, occurrence of pigeonite and diopside domains predominantly elongated along (100), formation of “100” exsolution lamellae, dissolution of the “100” lamellae, and predominant occurrence of “001” exsolution lamellae. All observations are in accordance with the exsolution mechanism of spinodal decomposition. After termination of the exsolution process, coarsening of the exsolution lamellae is observed. The “001” lamellae coarsen according to the rate law
415.
Tropical Deforestation and the Kyoto Protocol 总被引:11,自引:3,他引:8
Márcio?SantilliEmail author Paulo?Moutinho Stephan?Schwartzman Daniel?Nepstad Lisa?Curran Carlos?Nobre 《Climatic change》2005,71(3):267-276
The current annual rates of tropical deforestation from Brazil and Indonesia alone would equal four-fifths of the emissions reductions gained by implementing the Kyoto Protocol in its first commitment period, jeopardizing the goal of Protocol to avoid “dangerous anthropogenic interference” with the climate system. We propose the novel concept of “compensated reduction”, whereby countries that elect to reduce national level deforestation to below a previously determined historical level would receive post facto compensation, and commit to stabilize or further reduce deforestation in the future. Such a program could create large-scale incentives to reduce tropical deforestation, as well as for broader developing country participation in the Kyoto Protocol, and leverage support for the continuity of the Protocol beyond the 2008–2012 first commitment period. 相似文献
416.
417.
Nicolas Deichmann Manfred Baer Jochen Braunmiller Cécile Cornou Donat Fäh Domenico Giardini Monika Gisler Sarah Huber Stephan Husen Philipp Kästli Urs Kradolfer Martin Mai Silvio Maraini Ivo Oprsal Thomas Schler Danijel Schorlemmer Stefan Wiemer Jochen Wössner Adrian Wyss 《Eclogae Geologicae Helvetiae》2004,97(3):447-458
418.
P. Kaufmann E. Scalise Jr. R. E. Schaal J. R. D. Lépine D. Basu A. L. Ibañez 《Solar physics》1973,29(2):393-397
Solar mappings with moderate angular resolution at 7 GHz seem to support the hemispherical dependence of the sense of circular polarization being right-handed for the southern hemisphere, and left-handed for the northern hemisphere. One explanation of the effect can be found by taking into account the missing fields from active centers, emerging from one hemisphere and immersing into the other. 相似文献
419.
Earthquakes in Switzerland and surrounding regions during 2004 总被引:1,自引:0,他引:1
Manfred Baer Nicolas Deichmann Jochen Braunmiller Stephan Husen Donat F?h Domenico Giardini Philipp K?stli Urs KRadolfer Stefan Wiemer 《Eclogae Geologicae Helvetiae》2005,98(3):407-418
This report of the Swiss Seismological Service summarizes the seismic activity in Switzerland and surrounding regions during
2004. During this period, 677 earthquakes and 96 quarry blasts were detected and located in the region under consideration.
With 22 events with ML≥2.5, the seismic activity in the year 2004 was close to the average over the last 30 years. As in previous years, most of
the activity was concentrated in the Valais and in Graubünden. In addition, several moderate earthquakes occurred in the lower
crust below the northern Alpine foreland. Unusual was that five earthquakes were sufficiently strong to cause ground shaking
of intensity IV over large portions of the territory. Two were located in Switzerland (Liestal, ML 3.8, and Brugg, ML 4.0). The epicenters of the other three strong events were located outside Switzerland (Besan?on in the French Jura, ML 4.8, Waldkirch in southern Germany, ML 5.1, and Lago di Garda in northern Italy, ML 5.3). 相似文献
420.
We present detailed experimental results on the partitioning of rare earth elements (REE) between titanite and a range of different silicate melts. Our results show that Henry’s law of trace element partitioning depends on bulk composition, the available partners for heterovalent substitution, crystal composition, and melt composition. We illustrate that the partition coefficients for Sm depend very strongly on the bulk concentration of Sm in the system. The substitution mechanism, by which rare earth elements are incorporated into the crystal structure, plays an important role for trace element partitioning and also for the onset of Henry’s law. Our data show that there are clear differences between substitution mechanisms of major elements compared to elements which are present only as traces. Our experiments also clearly show that the onset of Henry’s law depends on the concentrations of the sum of all trace elements which are incorporated into the crystal by the same substitution mechanism. For geochemical modelling of magmatic processes involving titanite, and indeed other accessory phases, it is of crucial importance to first evaluate whether the REE, and other trace elements, are present as traces or as major elements, only then appropriate D values may be chosen. 相似文献