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91.
Adolfo L. Méndez Berhondo Ramón E. Rodríguez Taboada Paolo Zlobec 《Astrophysics and Space Science》2008,318(1-2):73-78
Pulsating structures recorded at 237 MHz that are associated to decimetric continuum enhancement during the September 9, 2001 solar radio burst are described. We analyzed the radiopolarimetric data recorded at the Trieste Solar Radio System (INAF—Trieste Astronomical Observatory—Basovizza Observing Station) with very high time resolution (1 ms) at metric frequencies. Two different types of pulsations that occur in about 4 minutes at the same frequency are described. The possible mechanisms are analyzed and some parameters of the associated magnetic structure are estimated. 相似文献
92.
Whether or not there are extensional detachment faults in the Alboran basement can be tested directly because a part of the Alboran Basin is now emerged. These detachments, related to crustal thinning beneath the Alboran Basin, occurred from the Aquitanian to Tortonian. The resulting extensional geometries can be described in general terms. During the Serravalian a considerable southwest extension of the basin took place, accompanied by south-southeast extension in the northern Gibraltar Arc. Other detachments affected by Serravalian extension can be found. The spreading of the Alboran was nearly coeval with roughly westward migration of the Gibraltar mountain front. 相似文献
93.
F. Díaz García J. R. Martínez Catalán R. Arenas P. González Cuadra 《International Journal of Earth Sciences》1999,88(2):337-351
An important detachment is described in the allochthonous Ordenes Complex, in the NW Iberian Massif, and its meaning is related
to the kinematics of contemporaneous convergent structures. The Corredoiras Detachment (CD) separates a hangingwall unit,
characterised by a medium-pressure metamorphic gradient, from a footwall high-pressure and high-temperature unit and an underlying
ophiolitic unit. An associated ductile shear zone, nearly 2000 m thick, developed in the lower part of the hangingwall unit,
where the Corredoiras Orthogneiss, a Lower Ordovician metagranite, was progressively transformed into augengneisses, mylonitic
and ultramylonitic gneisses. The attitude of the stretching and mineral lineation in the mylonites varies due to late refolding
at map scale, but the sense of movement can be estimated, being roughly top to the SE. According to crosscutting relationships,
the CD developed subsequent to the thrusting of the high-pressure/high-temperature unit onto the ophiolitic unit, and prior
to younger extensional detachments, upright folding and strike-slip tectonics. The geometric relationships of the CD with
the previous structures in the footwall unit, the subtractive character of the metamorphic gap between its hangingwall and
footwall, and the available isotopic data suggest that the CD is an early Variscan, ductile extensional detachment, the movement
of which was roughly simultaneous with the onset of thrusting of the allochthonous complexes over their relative autochthon.
Received: 17 November 1998 / Accepted: 4 April 1999 相似文献
94.
Summary Four parameters defining the Earth's tri-axial ellipsoid (E) have been derived on the basis of the condition that the gravity potential on E be constant and equal to the actual geopotential value (W0) on the geoid. The geocentric gravitational constant, the angular velocity of the Earth's rotation, the actual 2nd degree geopotential Stokes parameters and W0 are taken to be the primary geodetic constants defining E and its (normal) gravity field. 相似文献
95.
Vít Kárník 《Studia Geophysica et Geodaetica》1958,2(4):400-401
Резюме Приводятся результаты анализа записей двух камерных взрывов, имевших место 15-го Февраля 1958 г. в Баварии. Взрывы были регистрированы
двумя вертикальными электродинамическими сейсмографами, иаготовленными в Геофизическом институте ЧСАН и назначенными для регистравии
слабых тектонических толчков.
Address: Boční II, Praha 13-Spořilov. 相似文献
Address: Boční II, Praha 13-Spořilov. 相似文献
96.
R.M. Hernndez T.E. Jordan A. Dalenz Farjat L. Echavarría B.D. Idleman J.H. Reynolds 《Journal of South American Earth Sciences》2005,19(4):495-512
Marine transgression onto the South American continent took place at least twice in the Miocene along distinct paleogeographic corridors. The first event occurred between 15 and 13 Ma and the second between 10 and 5? Ma. Each event has particular dominant variables (tectonism, eustacy, sediment accumulation rate) that permitted the preservation of the record and development of the sea on the continent. The 15–13 Ma transgression was tectonically and eustatically controlled, flooding older sedimentary accommodation zones on the South American plate during a global high sea level, whereas the 105? Ma event was predominantly tectonically controlled, generated by tectonic loading created in the Cordillera Oriental fold-and-thrust belt. A new 7.72±0.31 Ma 40Ar/39Ar date from the Río Parapetí in Bolivia suggests that the 15–13 Ma transgression registered in Argentina produced no continental connection to the Caribbean transgression, registered in Bolivia, because of temporal constraints. 相似文献
97.
Modal Wave Number Tomography for South China Sea Front 总被引:10,自引:0,他引:10
1 .IntroductionTheSouthChinaSealiestothesoutheastpartoftheChinesecontinent.TheKuroshioflowsbytheeastsideoftheLuzonStraitfromsouthtonorthinwinter ,spring ,andautumn .TheKuroshioaf fectsnearcurrentfieldsandtemperaturefields,changingtheoceanenvironmentparametersandsoundpropagation .Thus ,theoceanacoustictomographytechniqueisofpotentialtolong term ,largescalemonitoringoftheocean .Themodalwavenumbertomographymethod (Rajanetal.,1 987;Frisketal.,1 989)isusedtoobtainthesoundspeedprofileinwatercol… 相似文献
98.
Sandra G García 《Transactions in GIS》2004,8(2):245-254
This study presents a spatiotemporal analysis tool, called Shyska. This tool allows the simulation and prediction of flash floods in semiarid basins. Shyska has been developed by Geographical Information System (GIS)‐embedded functions, allowing the integration of hydrometeorological information from modern technologies of data acquisition in real time. A Digital Elevation Model (DEM) is used in order to obtain the relevant parameters from the integrated rainfall‐runoff models. Some of its most relevant modules and methodology employed for its development are described. Case studies in basins of south‐east Spain illustrate the applicability of the proposed techniques. 相似文献
99.
In most of the studies on scale properties in the rainfall process, multifractal behavior has been investigated without taking into account the different rain generation mechanisms involved. However, it is known that rain processes are related to certain scales, determined by climatological characteristics as well as regional and local meteorological features. One of the implications derived from these correspondences is the possibility that the multifractal parameters of the rainfall could depend on the dominant precipitation generation mechanism. Fractal analysis techniques have been applied in this work to rainfall data recorded in the metropolitan area of Barcelona in the period 1994–2001, as well as to a selection of synoptic rainfall events registered in the same city in the period 1927–1992. The multifractal parameters obtained have been significantly different in each case probably showing the influence of the rain generation mechanisms involved. This influence has been revealed also in the analysis of the effects of seasonality on the multifractal behavior of rainfall in Barcelona. 相似文献
100.