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241.
Václav Hanuš Jiří Vaněk Gaston Sandoval Reviewer J. Zahradník 《Studia Geophysica et Geodaetica》1987,31(3):258-265
Summary The analysis of the geometry of distribution of earthquake foci occurring in the continental South American plate above the subducted Nazca plate reveals that in the region of Ecuador these earthquakes accumulate in 8 well-separated fracture zones. These zones are interpreted as a system of deep seismically active fractures induced in the continental plate by the process of subduction. It is shown that the position of known thermal springs and of observed hydrothermal alterations in Ecuador correlates with the outcrops of the fracture zones.
¶rt;aumuu an¶rt;u a mu muma num uu a¶rt; ¶rt;uu a¶rt; naa m mu mu anm 8 m¶rt; a a, m umnmua au uu amu a a muma um n ¶rt;uu. aam, m nmu um ma umuu uu¶rt;ma uu a¶rt; a¶rt;am ¶rt;a mu a .相似文献
242.
Summary The existence of global synchronous atmospheric oscillations with the period of about 1.4 hour is indicated in terms of a simple theoretical model of the circumpolar circulation.
u nu nm mmu ¶rt;u un uuu naa maua au am nu¶rt; 1,4 .相似文献
243.
Summary A system of 8 seismically active fracture zones was delineated on the basis of the distribution of earthquake foci in the continental lithosphere of Ecuador. The position and width of the outcrop, thickness, dip and maximum depth of the individual fracture zones were estimated and correlated with surface geological and tectonic phenomena, volcanism and hydrothermal manifestations. The existence and strike of the fracture zones was independently confirmed by the occurrence of historical disastrous earthquakes.
Visiting professors at Instituto Geofísico and Facultad de Geología, Minas y Petróleos, Escuela Politécnica Nacional, Quito (Ecuador). 相似文献
uma 8 uu amu a a aa a auu an¶rt;u a mu muma um a¶rt;a. u n¶rt; nu u uua a nmu, mua, u auaaua m¶rt; a . mau mu auu n¶rt;m¶rt;am a¶rt;u umuu aum mu u nmau nmu, mmu, au uu¶rt;mau nuu.
Visiting professors at Instituto Geofísico and Facultad de Geología, Minas y Petróleos, Escuela Politécnica Nacional, Quito (Ecuador). 相似文献
244.
Vladimír Schenk Vít Kárník Zdeňka Schenková Reviewer A. Zátopek 《Studia Geophysica et Geodaetica》1982,26(2):132-144
Summary The distribution of earthquake foci in the crust and the upper mantle indicates the position of mobile zones. Comparing epicentral maps of Central and Eastern Europe, known tectonic lines, results of deep seismic sounding and gravimetric survey enables a scheme of potential seismogenic zones, which correspond to active fault zones separating plates and blocks in the area, to be compiled. The level of earthquake activity varies along the investigated boundaries and can be considered as a measure of the intensity of the present geodynamic processes.Paper presented at the joint symposium AlO of the XVIIth General Assembly of the European Seismological Commission and of the 7th Annual Meeting of the European Geophysical Society, Budapest (Hungary), Aug. 21. – 29., 1980. 相似文献
245.
Summary The routine nulling procedure is modified on the basis of the theoretical decay of transient motion of the gravity meter beam and the time needed for its stabilizing. 相似文献
246.
a au au a ¶rt;am m ¶rt;uauu n¶rt;nu mau nua am u nu uu, m n amu n nua n uau mua mu. 相似文献
247.
Ivana Nemešová Eva Smítková Reviewer O. Zikmunda 《Studia Geophysica et Geodaetica》1982,26(2):176-186
Summary A model of a building cumulus structure is described. The one-stage model published in[1] was used to describe ascent of two cloudy parcels that a cloud is supposed to be formed of. The other ascent is assumed to take place after the first cloud element sinks back as a result of evaporative cooling. The numerical results and their evaluation are given for various rates of mixing at the cloud top level of the first cloud volume. 相似文献
248.
Vít Kárník Zdeňka Schenková Vladimír Schenk Reviewer K. Pěč 《Studia Geophysica et Geodaetica》1982,26(1):42-58
Summary The time development of three large sequences, Friuli 1976, Thessaloniki 1978 and Monte Negro-Albania 1979, was investigated by analysing the characteristics of the time distribution of magnitudes of the events, M(t), of average magnitudes,
(t), and of the number of events, n(t), as well as the strain release curves and the magnitude-frequency relations, N(M). The existence of time gaps and of an anomalous decay of the numbers of shocks before major events, as well as the oscillation of
( const b–1) may be considered as precursory phenomena. The clustering of events has been tested by the Poisson and negative binomial laws.Communication presented at the XVIIth General Assembly of the European Seismological Commission in Budapest, 21–29 August, 1980 under the title Properties of Seismic Regime and Recent Earthquake Sequences in Europe. 相似文献
249.
Gas composition and silica concentrations of well fluids are used in conjunction with pressure, temperature and enthalpy data to obtain a model of the drilled part of the Krafla geothermal field (Northeast Iceland).A magma chamber is located at 3–8 km depth under the field. Magmatic gases emanate from the chamber and travel via a channel reaching the surface at the Hveragil eruptive fissure. The composition of the gases is apparently modified on the way, in that sulphur, which presumably is in the form of sulphur dioxide to begin with, is removed on the way, and what remains is in the form of hydrogen sulphide at the end. It is suggested that the major removal mechanism is the deposition of pyrite and pyrrhotite during the passage of the gases through the hydrothermal system.The hydrothermal system is divided into a lower part whose temperature exceeds 300°C and whose fluids are to a varying extent affected by the magmatic gases, and an upper part whose temperature is ca 200°C. This upper part is a run-off from the lower part but the magmatic effects have mostly disappeared there. 相似文献
250.