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111.
112.
The unusual 80 km diameter Noachian-aged Asimov crater in Noachis Terra (46°S, 5°E) is characterized by extensive Noachian-Hesperian crater fill and a younger superposed annulus of valleys encircling the margins of the crater floor. These valleys provide an opportunity to study the relationships of gully geomorphology as a function of changing slope orientation relative to solar insolation. We found that the level of development of gullies was highly correlated with slope orientation and solar insolation. The largest and most complex gully systems, with the most well-developed fluvial landforms, are restricted to pole-facing slopes. In contrast, gullies on equator-facing slopes are smaller, more poorly developed and integrated, more highly degraded, and contain more impact craters. We used a 1D version of the Laboratoire de Météorologie Dynamique GCM, and slope geometries (orientation and angle), driven by predicted spin-axis/orbital parameter history, to assess the distribution and history of surface temperatures in these valleys during recent geological history. Surface temperatures on pole-facing slopes preferential for water ice accumulation and subsequent melting are predicted to occur as recently as 0.5-2.1 Ma, which is consistent with age estimates of gully activity elsewhere on Mars. In contrast, the 1D model predicts that water ice cannot accumulate on equator-facing slopes until obliquities exceed 45°, suggesting they are unlikely to have been active over the last 5 Ma. The correlation of the temperature predictions and the geological evidence for age differences suggests that there were two phases of gully formation in the last few million years: an older phase in which top-down melting occurred on equator-facing slopes and a younger more robust phase on pole-facing slopes. The similarities of small-scale fluvial erosion features seen in the gullies on Mars and those observed in gullies cut by seasonal and perennial snowmelt in the Antarctic Dry Valleys supports a top-down melting origin for these gullies on Mars. 相似文献
113.
Summary The data of borehole resistivity logs were collected, analysed, classified and a contour map of electrical conductance of the sedimentary complex overlying the crystalline basement of the Czech Republic was computer-generated. The map contributes to estimating the distortion fields produced by conductance variations in the surface layer. Information on the basement relief is also obtained from the contour map patterns. 相似文献
114.
Oldřich Novotný Т. А. Проскурякова Э. В. Воронина Рецензенm V. Kárník 《Studia Geophysica et Geodaetica》1981,25(2):160-166
m¶rt; ¶rt;VII ¶rt;a¶rt; nu auma mmuu ¶rt;unu u . ¶rt;u mu u na mmua ¶rt;unua ua ¶rt; nu aa—ua, ¶rt;ma a¶rt; ¶rt;a. 相似文献
115.
Summary In Haskell's formulation the dispersion equation is expressed by means of matrices, the elements of which are real or pure imaginary [2]. In the present paper different matrices have been found, which have only real elements.Dedicated to 90th Birthday of Professor Frantiek Fiala 相似文献
116.
Summary The problem of the electromagnetic field distribution, which is described by Helmholtz equation, is solved by treating the finite difference approximation. The field of H-polarization is studied on a bounded region consisting of blocks with different electrical conductivities separated by interfaces of a general form. 相似文献
117.
u¶rt;um u ¶rt; n¶rt;u mum n -nuuu ¶rt;u um um ¶rt;¶rt; ¶rt; mm. um m u m u m¶rt;. 相似文献
118.
Karel Pěč Jana Pěčová Oldřich Praus Reviewer M. Hvoždara 《Studia Geophysica et Geodaetica》1988,32(3):300-312
Summary The theory of the multivariate coherence analysis(spectral domain approach) is developed for calculating single- and inter-station transfer functions and corresponding vector induction characteristics from time variations of the geomagnetic field components. An alternative approach of calculating similar induction characteristics using a time domain algorithm is shown.
aam mu m aaua(nma n¶rt;¶rt;) nuuu ama ¶rt;-u -mau n¶rt;am u u mmmu m aamumu u¶rt;uu n anua auau mau aum n u. u¶rt;um ma m¶rt; u aau aamumu u¶rt;uu nm ama amu un mua um. nuam aum na auu am u aamum ¶rt; n ama naam.相似文献
119.
Václav Petr Jana Pěčová Oldřich Praus Reviewer M. Hvoždara 《Studia Geophysica et Geodaetica》1985,29(2):169-190
Summary Magnetic variations were recorded along three profiles crossing the southeastern margin of the Bohemian Massif. The data were processed in order to get induction vectors (Wiesevectors) and in-phase and out-of-phase induction vectors (Schmucker-vectors). Several events of field variations were separated into external and internal parts. The same events were also treated by a physical-statistical approach. Taking into account these results, we were able to delineate a zone of electrical inhomogeneity. It is in close relation to the Moravo-Silesian lineament. The depth of the internal anomalous field source was estimated at 20 to 25 km.
¶rt;a u uuau n uu n nu, nu — u. u¶rt;uu ( u), n u u n¶rt; u n u¶rt;uu ( ), n ¶rt;u n uau u u u n au ¶rt; uu-uuu ¶rt; u ¶rt;¶rt;u na¶rt; nu -uu . ¶rt; au uu a n a u n¶rt; 20–25 .相似文献
120.