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Jaromír Janský Libuše Ruprechtová Bernd Tittel Reviewer A. Zátopek 《Studia Geophysica et Geodaetica》1979,23(2):144-149
Summary The average dependence of the calibration function q and the travel-time residuals t on the depth and distance of the source has been derived for individual branches of PKP waves using earthquakes from the SW Pacific Ocean (distance interval 147°–159°, depths 0–700 km). The analysis of very distant shocks of all depths according to the regional PKP travel time tables can be completed by the magnitude determination. 相似文献
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Summary The amplitude-distance function of the short period PKP waves, recorded at Macedonian seismological stations from sources in the SW Pacific Ocean, is investigated. The dependences found for sources with depths under 100 km and for sources with depths over 500 km are compared with the results of some other authors. 相似文献
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Summary This paper shows some examples of theoretical seismograms of short period PKP waves calculated by the zero approximation of the ray theory. The influence of the epicentral distance, source time function and the Earth's crust on the form of the seismograms is shown. 相似文献
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Magnetic susceptibility of 72 cambisol profiles from the vicinity of the Vír dam, NW Moravia was measured. The enhanced susceptibility
of topsoil, particularly of the horizon O, was assessed from the aspect of vegetation setting and magnetic mineralogy. Magnetic
susceptibility variations with field and temperature as well as frequency dependent susceptibility were applied to indicate
magnetic carriers. It was found that the enhanced magnetic susceptibility is caused very likely by the presence of maghemite
and magnetite of various grain sizes. Magnetic minerals are pedogenic in origin in all three horizons, while in the O and
A horizons they are mostly anthropogenic in origin. Magnetic susceptibility was correlated with contents of trace elements
Mo, Cu, Pb, Zn, Ag, As, Cd, Sb, Bi, Hg, Se, furthermore with TOT/C, TOT/S, and 137C. The close association of susceptibility with Pb, Sb and Hg, or also with Mo, As, Se and their similar depth variations
suggest a slight anthropogenic input in soils from a long-distant source. The same is valid for 137C, its strong correlation with magnetic susceptibility has been found. 相似文献
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Ulrych Jaromír Krmíček Lukáš Teschner Claudia Řanda Zdeněk Skála Roman Jonášová Šárka Fediuk Ferry Adamovič Jiří Pokorný Richard 《Mineralogy and Petrology》2017,111(5):761-775
Mineralogy and Petrology - Tachylytes from rift-related volcanic rocks were recognized as: (i) irregular veinlets in host alkaline lava flows of the Kozákov volcano, Czech Republic, (ii)... 相似文献
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Ulrych Jaromír Cajz Vladimír Pivec Edvin Novák Jiří Karel Nekovařík Čestmír Balogh Kadosa 《Studia Geophysica et Geodaetica》2000,44(2):346-351
Three independent volcanic suites have been recognised in W Bohemia: (i) the old unimodal alkaline ol. nephelinite-tephrite (29-19 Ma) in the Ohe Rift, (ii) two contemporaneous weakly (trachybasalt/trachyandesite-trachyte/rhyolite; 13-11 Ma) and strongly (ol. nephelinite-tephrite/basanite; 12-8 Ma) alkaline series in the flank of the Cheb-Domalice Graben formed by the Teplá Highland and (iii) the young unimodal ol. melilitite/ol. nephelinite alkaline suite (2.0-0.12 Ma) at the intersection of the above mentioned structures in the Cheb Basin. The magmas of all the suites are mantle-derived and, in the case of the Cheb-Domalice Graben series, associated with the AFC process. Two main fault systems: (i) ENE-WSW and (ii) NNW-SSE are developed in W Bohemia, corresponding to the directions of the two prominent taphrogenic structures. The southwesterly continuation of the Ohe Rift across the Mariánské Lázn Fault is marked by volcanics only. 相似文献
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Jaromír Ulrych Emil Jelínek Zdeněk Řanda Felicity E. Lloyd Kadosa Balogh Ernst Hegner Jiří K. Novák 《Chemie der Erde / Geochemistry》2010,70(4):319-333
High-Ti melanephelinite (3.8–5.9 wt% TiO2), medium-Ti (phono)tephrite (2.7–3.1 wt% TiO2), and low-Ti olivine melanephelinite/basanite (1.9–2.3 wt.% TiO2) are subordinate rock types in the central European Cenozoic Volcanic Province. A contrasting melanephelinite to (phono)tephrite series occurs in the Lou?ná–Oberwiesenthal Volcanic Centre (37–28 Ma) and also as satellite volcanic bodies (26–12 Ma) together with olivine melanephelinite/basanite (17–20 Ma) on the southwestern periphery of the Kru?né hory mountains (Erzgebirge). The volcanic rocks intrude the Variscan basement of the uplifted shoulder of the Oh?e/Eger Rift in the Kru?né hory mountains of the Bohemian Massif. Low Mg# (44–59) and Cr, Ni contents and enrichment of LILE, Zr, Hf, Nb, Ta, U, Th and LREE in the high-Ti melanephelinites contrast with the composition of primitive low-Ti olivine melanephelinites/basanites displaying high Mg# (63–74) and high contents of compatible elements. The high-Ti melanephelinites reveal a wide range in initial 87Sr/86Sr of ca. 0.7034–0.7038 and εNd of 2.4–4.9. The low-Ti melanephelinites show an overlapping range of initial 87Sr/86Sr of ca. 0.7035–0.7036 and εNd of 4.3–5.5. The large variation in initial 87Sr/86Sr ratios at similar εNd values in those rock types is interpreted as evidence for melting of metasomatized lithospheric mantle sources comprising K-bearing phases with radiogenic Sr. Modification of the olivine-free alkali basaltic magmas by differentiation or crustal contamination could give rise to the medium-Ti (phono) tephrites. The initial isotope ratios of all samples are consistent with HIMU-mantle sources and contributions from lithospheric mantle. The olivine-free melanephelinitic rocks often contain alkali pyroxenite–ijolite xenoliths with initial 87Sr/86Sr ratios of ca. 0.7036 and εNd of 3.0. We interpret these xenoliths as samples of an intra-crustal alkali complex derived from similar mantle sources as those for the basaltic volcanic rocks. 相似文献