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151.
152.
Summary The magnetic phases of natural pyrrhotites were studied by the method of powder patterns, the chemism of the magnetic phases by means of the electron microprobe method, and the crystal phases by etching the polished sections. The method of powder patterns distinguished the ferrimagnetic and antiferromagnetic phases in the transition-type pyrrhotites. The method of absorbed electrons lead to the discovery that both phases have a different chemical composition and that the ferrimagnetic phase has a lower denisty and an average atomic number. The linear and point-by-point analysis disclosed that the ferrimagnetic phase has a lower weight content of Fe and a higher weight content of S than the antiferromagnetic phase. Both the magnetic phases displayed different properties when etched, and therefore they not only have a different chemical composition, but also a different crystal structure. The necessity of studying the image of the absorbed electrons and the image of the etched surface of the polycrystalline samples of pyrrhotites of the transition type separately on individual grains was pointed out. 相似文献
153.
S. P. Burlatskaya Václav Bucha Reviewer A. Janáčková 《Studia Geophysica et Geodaetica》1972,16(4):407-410
a n¶rt;u¶rt; amuu amua uuu anmuaum n a n¶rt;u 8500 m nm um au aam m uuu m naama. ¶rt;u u ¶rt;a ¶rt; u ¶rt; m¶rt; mumu auu nau nuu aau mama [1–3] (Puc. 1.B). nma aau auau (Puc.2) mnaua m m m¶rt;a, ¶rt; au n¶rt; amu u, m n¶rt;u 2- ma m, mmu naa auu nu¶rt; n¶rt;a 1000 m u 350 m, au a aumu, mmm 80%- mmu. am au ¶rt;a u anmu ¶rt; m¶rt; mumu (mum) naa auu u¶rt; ma u ¶rt; m naama[5] (Puc. 3). uma a mam nma aaua naaa auu nu¶rt; n¶rt;a 750 m, 200 m u a — 300 m. (Puc. 4.) nmu u ¶rt;a nma amua an¶rt;u n¶rt;u n u ma m (au) auumu m ¶rt;m m (Puc. 5). aa a m¶rt;m nu naamaum n aam ¶rt;uu mu au, anum¶rt;a m uua nm m¶rt;a.
Dedicated to Academician Alois Zátopek on His 65th Birthday 相似文献
Dedicated to Academician Alois Zátopek on His 65th Birthday 相似文献
154.
Vladimír Kropáček Miroslav Krs Reviewer F. Janák 《Studia Geophysica et Geodaetica》1971,15(2):161-172
Summary The paper deals with the magnetic properties of the natural minerals haematite, ilmenite and pyrrhotite. The natural remanent magnetization Jn, the volume susceptibility , the specific magnetization of saturation so, the Curie temperature , the A.C. demagnetization of natural remanent magnetization, the thermal demagnetization Jn, the temperature dependence of the specific magnetization of saturation, and several other parameters were determined for the individual sets of minerals. Since natural minerals can and do contain various heterogeneous and isomorphic admixtures, their magnetic properties may change depending on the content and type of these admixtures. Therefore, all the investigations of the magnetic properties described in this paper were carried out with extensive sets of minerals, representing various Czechoslovak and world localities. A number of interesting results were obtained from the executed experiments, e.g., the different stability of the natural remanent magnetization of haematite with respect to A.C. demagnetization, the presence and type of heterogeneous inclusions in ilmenite, the phase changes connected with the -transition in natural pyrrhotites, etc. The types of distributions of the investigated values of the magnetic properties were also determined. 相似文献
155.
Summary The mean curvature of the equipotential surface and the vertical gradient of gravity are expressed in terms of a development into a series of spherical harmonics [1, 2, 4], neglecting terms of the order of 10–8. The curvature anomalies have been computed using the satellite data [3]. The symbols used are the same as in [5].Dedicated to 90th Birthday of Professor Frantiek Fiala 相似文献
156.
157.
Břetislav Beránek Milica Mayerová Milada Zounková Alexander Guterch Rufin Materzok Jan Pajchel Reviewer J. Vaněk 《Studia Geophysica et Geodaetica》1973,17(3):205-217
Summary The paper deals with the results of DSS measurements along international profile VII, carried out by Czechoslovak and Polish geophysicists in 1970 – 71. The profile situation is shown in Fig. 1. By 1971 part of the profile in the region of the Bohemian Massif between points 1 and 3 and in Poland between points 5 and 7 had been surveyed (Fig. 2). The seismograms were used to construct the travel-time curves of the fundamental types of waves PK, PM, Pn (Fig. 4). The mean velocities were computed from the travel-time curves of the reflected waves (PM and PK) and the refracted waves (Pg). Isolines of the mean velocities could be constructed for the region of the Bohemian Massif (Fig. 6). The velocity data found were used for the depth interpretation of the travel-time curves of the principal types of waves and to construct a seismic section (Fig. 8). In the region of the Pre-Sudeten block the thickness of the crust was found to be 34–37 km, and in the Sudeten it increased to 40 km. Towards the south the thickness of the crust gradually reduces to 30 km in the system of the Luice faults. In the Bohemian Cretaceous the thickness of the crust is about 30 km. Further to the south, in the region of the Moldanubicum, the thickness of the Earth's crust increases rapidly, and at the southern border of the Central Bohemian pluton it reaches values of about 42 km. 相似文献
158.
auamaumuu am, n u a¶rt;u nuu n ¶rt;a 2, 2, 1 u 1 (u. 1–4). na ¶rt;a ¶rt;am au ¶rt;um au an¶rt;u mu naam. a n¶rt;aam unam nu nuu nna m uu u u mmu mam ¶rt; uu u a a mau n.
Vorgetragen am 2. Internationalen Symposium Geodäsie und Physik der Erde, Potsdam, Mai 1973. 相似文献
Vorgetragen am 2. Internationalen Symposium Geodäsie und Physik der Erde, Potsdam, Mai 1973. 相似文献
159.
Václav Bucha Josef Horáček Reviewer A. Janáčková 《Studia Geophysica et Geodaetica》1973,17(4):321-336
Summary The paper brings a brief geological asessment of the sedimentational cycles, analyses the methods of collection and investigation of samples and the representativeness of the results obtained. Problems of magnetic cleaning and the types of demagnetization curves investigated are discussed. The continuous nature of the variations of the magnetic declination, inclination and remanent magnetization, determined by palaeomagnetic investigation of Quaternary sediments, is also discussed. The conclusion contains the principal facts about the dynamics of the geomagnetic field in the Quaternary and points out the possibility of applying them to the theory of the geomagnetic field, as well as to geological correlations. 相似文献
160.