SIXE: A Payload for MINISAT-02     

Jordi Gómez-Gomar  Jordi Isern  Eduardo Bravo  Franco Giovannelli  Cesare De La Padula 《Astrophysics and Space Science》1998,263(1-4):389-392

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Do Solar Flares Affect Total Ozone?     

Diego Marin  Jan Laštovička 《Studia Geophysica et Geodaetica》1998,42(4):533-539

An analysis of total ozone from Hradec Králové (50.25°N, 15.21°E) and of radio wave absorption in the lower ionosphere at 1539 kHz (reflection point 50.3°N, 11.8°E) shows that there is no detectable effect of strong solar flares in total ozone, no correlation between total ozone and absorption on a day-to-day time scale, and that strong solar flares do not affect this correlation. Thus the long-term correlation of monthly average values (Alberca et al., 1996) is not reproduced on a day-to-day time scale, and the effects of strong geomagnetic storms in total ozone (Latovika et al., 1992; Mlch and Latovika, 1996) have no counterpart in effects of strong solar flares.  相似文献   

Premiers résultats d'une étude géophysique sur le flanc nord des glissements de Storegga (Norvège)     

Hervé Nouzé  Isabelle Contrucci  Jean-Paul Foucher  Bruno Marsset  Yannick Thomas  Estelle Thereau  Alain Normand  Éliane Le Drezen  Stéphane Didailler  Jean-Pierre Regnault  Sandie Le Conte  Stéphanie Guidart  Wim Lekens  Simon Dean  Alexandre Throo 《Comptes Rendus Geoscience》2004,336(13):1181-1189

The Storegga slides, off Norway, are among the largest submarine slides ever known on a continental slope. The HYDRATECH cruise on N/O Le Suroît aimed at a high-resolution survey of an area at the northern boundary of the slides. This survey images in great detail the bottom simulating reflector (BSR) extent and properties, the various fluid escape structures and the sediment deformations. The combination and the quality of the data help to understand the still poorly constrained relationships between fluid escapes, gas hydrates and slope stability in the survey area. To cite this article: H. Nouzé et al., C. R. Geoscience 336 (2004).  相似文献   

南菲律宾地区类埃达克岩和富铌玄武质熔岩的成因   总被引：7，自引：3，他引：7  

PaternoRCASTILLO 《岩石学报》2002,18(2):143-151

埃达克岩（adakite)最初 是指由消减板片玄武岩物质熔融形成的富硅、富钠、高Sr/Y和La/Yb比值的弧火山熔岩。它通常产在会聚带，这个部位的年轻的、因而仍然是热的大洋板片正在发生俯冲消减。富铌的岛弦玄武央进则是吕等到高碱的镁铁质熔岩，它们相对于正常的岛弦玄武岩含有较多的高场强元素（HFSE）。这些玄武岩通常与埃达克央共生， 这一组合是直被用于论证他们的高HFSE含量是因为他们的地幔源区受到板片来源的熔体的交代。先前的区域研究结果表明，南菲律宾是埃达克岩和富铌岛孤玄武岩的一个典型产地。然而最近的详细研究显示，尽管该地区的一些岛弧火山岩是类埃达克岩的，但是它们很可能是来自地幔楔的母岩浆的分异作用的产物，而这里的地幔楔主要是受沉积来源的成分交代的，此外，菲律宾南部最典型的富铌熔岩中HFSE的富集，也很有可能是起因于似乎是西太平洋边缘特有的富集地幔组分的熔融。这些结果提出了如下问题：南菲律宾是否存在真正的板片来源的熔体？这里的富铌岛弧 熔岩是否起因于地幔楔被这种熔体交代？  相似文献   

Electric conductivity of Fe-Ti minerals     

Marcela Laštovičková  Vladimír Kropáček  Reviewer F. Janák 《Studia Geophysica et Geodaetica》1979,23(2):199-203

a mua n¶rt;um u mnama auum uma mnam 200–900°C ¶rt; ummuu u ama Fe-Ti ua (amum,amum, uum u mu). n numa ¶rt;a n¶rt;m mun au mn¶rt;mu u au uu amuauu. a ma u mm naam n¶rt;u m-auu m¶rt;.  相似文献   

Stromboli and its 1975 eruption     

G. Capaldi  I. Guerra  A. Lo Bascio  G. Luongo  R. Pece  A. Rapolla  R. Scarpa  E. Del Pezzo  M. Martini  M. R. Ghiara  L. Lirer  R. Munno  L. La Volpe 《Bulletin of Volcanology》1978,41(3):259-285

On November 4, 1975 in the evening, an eruption took place at Mt. Stromboli. On the following day lava flowed on the Sciara del Fuoco downward to the sea, accompanied by an intense explosive activity at the crater plane. Direct observations on the volcanic activity were carried out since November 6 while a seismic survey was made from Nov. 7 to 12. The total volume of the lava outpoured during this period of activity that lasted 21 days, was estimated to be about 10⁴ m³. This paper reports the results of direct observations, and of the petrological, radioactive disequilibria and seismic activity studies performed for this eruption. The eruption was preceded by an insignificant change of seismic activity, which was monitored by a seismic station located about 2 km East of the crater. A shallow seismicity was strietly related to crater explosions accompanying the eruptive phenomenon. Radioactive disequilibria showed a lack of disequilibrium between²²⁸Ra and²³²Th explainable in terms of a fast rising of magma in the conduit. Chemical analyses of lava samples and deep seismic sounding data indicate a correspondence between the depth (10–15 km) at which crystallization pressure of phenocrysts occurs and a low velocity laver.  相似文献   

The electric properties of eclogites from the Bohemian Massif under high temperatures and pressures     

M. Laštovičková  E. I. Parchomenko 《Pure and Applied Geophysics》1976,114(3):451-460

Summary The D.C. and A.C. electric conductivity and the dielectric constant of a set of 8 eclogites from the Bohemian Massif is studied under high temperatures (200–900°C) and pressures (up to 20 kb). The electric conductivity of the studied eclogites is strongly affected by the content of symplectite minerals: their conductivity increases with their concentration. The average increase of conductivity with pressure between 1 kb and 20 kb is about 50% and is manifested particularly below 4 kb. The correlation between the electric conductivity and the dielectric constant is very high (r=0.975) and allows for the values of one parameter to be estimated from those of another.  相似文献   

Winter anomaly observations at the Panská Ves Observatory (Czechoslovakia), 1971–1973     

Jan Laštovička  Pavel Tříska  Reviewer J. Prokop 《Studia Geophysica et Geodaetica》1976,20(4):404-408

Summary The results of the winter anomaly observations at the Panská Ves Observatory on 2775 kHz and 2614 kHz (A3 method, f_eq1 and 0.8 MHz) are studied for the winters of 1971/72 and 1972/73. Ionospheric responses to minor (1972) and major stratospheric warmings are found to be different and relatively small. A regular winter-anomaly background absorption increase with a maximum in January was observed during both winters studied. Magnetic storms are found to play an insignificant, if any, role in the winter-anomaly phenomenon. The relation between magnetic activity and ionospheric absorption seems to be better in non-anomalous periods.  相似文献   

Oceanographic implications of features in NOAA satellite visible imagery     

P. E. La Violette  S. Peteherych  J. F. R. Gower 《Boundary-Layer Meteorology》1980,18(2):159-175

The sunglint areas of the ocean in NOAA satellite visible imagery appear as long swaths that extend from the northern extremes of the North Temperate Zone to the southern extreme of the South Temperate Zone. Examples are shown of complex features apparent in the sunglint area of visible imagery that closely match ocean-related thermal features in the companion infrared imagery. Various interpretations of these features are discussed. Data from the first phase of the Grand Banks Experiment (June 1978) are presented which demonstrate that such sunglint features are related to the strong ocean frontal processes present in this area. Although some of the features may be associated with fog or mist, side-looking airborne radar imagery collected during the experiment confirms the presence of surface roughness variations. The observations strongly suggest that these roughness variations are due to changes in the stability of the atmospheric boundary layer caused by the different surface water temperatures present in the area. The results demonstrate the usefulness of NOAA visible imagery as a tool to aid in the understanding of synoptic ocean processes, and suggest an important application for satellite and airborne synthetic aperture radars in mapping the roughness changes associated with ocean current systems.  相似文献   

A method of measuring the temperature dependence of the electrical conductivity of rocks     

Marcela Laštovičková  Jiří Popule  Reviewer J. Buben 《Studia Geophysica et Geodaetica》1974,18(4):370-380

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