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171.
This report of the Swiss Seismological Service summarizes the seismic activity in Switzerland and surrounding regions during 2008. During this period, 451 earthquakes and 75 quarry blasts were detected and located in the region under consideration. The three strongest events occurred in the Valais, near Lac des Toules (ML 3.6), and in Graubünden, near Ilanz (ML 3.7) and Paspels (ML 4.0). Although felt by the population, they were not reported to have caused any damage. However, with a total of only 15 events with ML ≥ 2.5, the seismic activity in the year 2008 was far below the average over the previous 33 years.  相似文献   
172.
In September 2007 Föllmi and coauthors requested the approval of four lithostratigraphic terms of the Swiss Committee of Stratigraphy (SCS). These terms were to be used in their publication on the Cretaceous in the Helvetic realm (Föllmi et al. 2007). At its meeting on October 18, 2007, the SCS decided the following: The Tierwis Formation (replacing the Drusberg Formation) was accepted, with the reserve that a section at Tierwis should be published in the near future. For the former “Lower Orbitolina Beds” the term Rawil Member was accepted, but here too a better type section than the one at Rawil Pass should be published. The term Rohrbachstein bed should not be used as a formal unit because it describes only a minor lithologic variation within the Grünten Member. The term Plaine Morte bed for a thin condensed horizon can not be accepted due to the fact that its definition is based mainly on biostratigraphy. Furthermore, the duplication a locality term which is in use for a previously established lithostratigraphic unit should be avoided.  相似文献   
173.
Abrahamson and Dinniss [2000. Ball lightning caused by oxidation of nanoparticle networks from normal lightning strikes on soil. Nature 403, 519–521] proposed a theory of ball lighting in which silicon nanoparticles undergo slow oxidation and emit light. Paiva et al. [2007. Production of ball-lightning-like luminous balls by electrical discharges in silicon. Physical Review Letters 98, 048501] reported that an electric arc to silicon produced long-lasting luminous white spheres showing many characteristics of ball lightning. We show experimentally that these consist of burning molten silicon spheres with diameters in the 0.1–1 mm range. The evidence of our experiments leads us to propose that a subset of ball lightning events may consist of macro-scale molten spheres of burning metallic materials likely to be ejected from a conventional lightning strike to earth.  相似文献   
174.
175.
During the last main phase of glaciation (26–13 ka) an ice‐cap developed in southwest Ireland and ice, from a dispersal centre in the vicinity of Kenmare, flowed north through the Gap of Dunloe in the Macgillycuddy's Reeks. On surrounding hillsides a weathering limit separates ice‐moulded bedrock, on low ground, from frost‐weathered terrain above. Assessment of bedrock dilation joint characteristics, Schmidt hammer R‐value data and clay‐sized mineral contents of basal soil samples, demonstrate significant contrasts in the degree of weathering above and below this limit. The weathering limit declines in altitude along former ice flow‐lines and is confluent with morainic deposits on the eastern side of the Gap. This supports the assertion that the high‐level weathering limit is a periglacial trimline that marks the former maximum upper limit of the body of ice which occupied the Gap of Dunloe during the Last Glacial Maximum (LGM). Reconstruction of the former ice‐surface profile from periglacial trimline limits on the eastern side of the Gap yields a mean estimate for basal shear stress of 106.5 kPa. This value suggests that the ice mass which occupied the Gap of Dunloe at the LGM was warm based and flowed on a bedrock substrate. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
176.
The Geophysics Directorate of Phillips Lab is engaged in several Galactic structure studies. These studies involve a reprocessing and analysis of the IRAS measurements and experiments on the next two infrared satellites, the Midcourse Space Experiment (MSX) and the Infrared Space Observatory (ISO). A collaboration with the Deep Near Infrared Survey (DENIS) will provide complementary coverage of the same Galactic Plane fields surveyed by MSX and ISO.  相似文献   
177.
The effects of tropical storm Dennis were documented in the coastal waters of South Carolina during August 1981. Phytoplankton photosynthesis vs. irradiance curves showed initial depression of the parameter a followed by three- to five-fold increase of both a and the asymptotic maximum rate of photosynthesis PmB. Productivity rates were depressed in most samples immediately after the storm. Surface samples at the inshore stations were around 50 mg C m?3 h?1 at saturating light intensities, while the offshore station rates were around 10 mg C m?3 h?1. After a 10-day lag these rates had increased to about 200 mg C m?3 h?1 inshore and 75 mg C m?3 h?1 offshore. These changes are thought to be primarily caused by changes in species composition. Some of the dominant diatom species changed and dinoflagellate species were introduced. No significant changes in nutrient concentrations were observed. Transient depressions of water temperature, salinity and light intensity may have contributed to the observed changes.  相似文献   
178.
Differential photometry of this K1 IV–III p RS VNn-type binary in 1978–79, 1979–80, and 1980–81 at eight different observatories shows that the variability, discovered orignally by Herbst, is periodic. The mean of three different determinations of the photometric period was 24d.39±-0d.03, about 1% shorter than the orbital period of 24d.649 determined spectroscopically by Harper. The total range observed during these three years was 5 m .60<V<5 m .85. The light curve was nearly sinusoidal but always noticeably asymmetric, with the sense reversing sometime between 1979–80 and 1980–81.  相似文献   
179.
Data on biota and nutrients in solar ponds of a saltworks near Burgas, Bulgaria, were obtained. Surveys of the biota were undertaken, and records from management officials gave information on biological and physical conditions related to salt production. The decrease in the quality and quantity of sodium chloride harvested that began 10 to 15 years before the study, may be related to the high levels of plankton, combined nitrogen and phosphate, and the large accretion of bottom sediments and density of benthic communities. Biological management can improve the quality and quantity of the sodium chloride produced by the saltworks.  相似文献   
180.
Editors' note     
Pure and Applied Geophysics -  相似文献   
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