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Using a set of synthetic P‐ and S‐wave onsets, computed in a 1D medium model from sources that mimic a distribution of microseismic events induced by hydrofrac treatment to a monitoring geophone array(s), we test the possibility to invert back jointly the model and events location. We use the Neighbourhood algorithm for data inversion to account for non‐linear effects of velocity model and grid search for event location. The velocity model used is composed of homogeneous layers, derived from sonic logging. Results for the case of one and two monitoring wells are compared. These results show that the velocity model can be obtained in the case of two monitoring wells, if they have optimal relative position. The use of one monitoring well fails due to the trade‐off between the velocity model and event locations. 相似文献
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基于P波和S波的谱震级特征对汶川地震进行了定量研究,可以看出P波和S波的最大谱震级出现在不同的周期上。对这一现象的构造物理意义进行了讨论,推测相对于P波而言,地震发生期间辐射的S波能量来自异常大的震源体积。选择部分全球地震的谱特征为背景,对汶川地震的体波谱震级特征进行了分析,结论是汶川地震的特征与其所处的周边环境是一致的。 相似文献
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Jaromir Demek 《Geoforum》1978,9(1):29-34
The main object of study of geography is the landscape sphere that includes the surface of our planet. The landscape sphere differs from the other geospheres by displaying unusual complexity and consists of structured sets of components which exhibit discernible relationships with one another and operate as a system. The functioning of the landscape sphere is conditioned by the interrelationships of components, as well as by the transfer of mass and energy from one part of the landscape sphere to another in the form of streams of mobile elements. The author is using the name geosystem for determination of this system of planetary dimensions. The landscape sphere may be further divided into subsystems exhibiting characteristic features which facilitate their identification and delimitation.Territorial differentiation of the landscape sphere, on the basis of the law of zonality, produces horizontal, latitudinal and vertical zones called by author geoms. These geoms may be further subdivided into geosystems of smaller dimensions called geochoras. The basic geochora is the landscape. In most landscapes the key elements in these geosystems are controlled by Man and so-called cultural landscapes are developed. The cultural landscapes are parts of the landscape sphere within which natural and socioeconomic geosystems co-exist. The author further distinguishes cultured, disturbed and devastated landscapes. The study of cultural landscape is amongst the most difficult fields of investigation, but such studies are of great significance in terms of predicting future environmental developments. 相似文献
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Ocean Dynamics - A three-dimensional, regional coupled ice-ocean model based on the open-source Community Earth System Model has been developed and implemented for the Baltic Sea. The model... 相似文献
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Wolfgang Seifert Dieter Rhede Hans-Jürgen Förster Rudolf Naumann Rainer Thomas Jaromir Ulrych 《Mineralogy and Petrology》2014,108(5):645-662
Macrocrysts of corundum, ilmenite, and spinel-group minerals from alluvial deposits of the Eger Rift were studied for composition, texture, and mineral inclusions. All macrocrysts show usually magmatic corrosion textures indicating disequilibrium with the transporting alkali-basalt magma. Corundum grains, exclusively sapphires, were classified by trace-element signatures as magmatic and metamorphic types. Some sapphire grains show erratic compositions that may have resulted from a metasomatic overprint. The inclusion inventory of magmatic corundum suggests crystallization from a differentiated alkaline silicate melt. Corundum itself was never observed as an inclusion mineral. Magnesium- and Fe3+-rich ilmenite, described as typical mantle-derived species, is the dominant heavy mineral in almost all alluvial deposits of the Eger Rift. Most discrete macrocrysts are similar in appearance and composition to kimberlite- and basanite-related ilmenite. Ilmenite included in alluvial corundum and zircon grains differ from the bulk of discrete ilmenite grains by larger concentrations of Nb and Mn. The mantle origin of the Mg–Fe3+-rich ilmenite is confirmed by compositional and thermo-barometric comparison with ilmenite from clinoproxenitic and hornblenditic xenoliths, which probably originated in the Moho region. The Fe–Ti two-oxide geothermometry and oxygen-barometry of coexisting ilmenite–magnetite pairs yield equilibrium temperatures between 900 and 1,080 °C and oxygen fugacities log10fO2 between ?0.1 and 1.1 (relative to the NNO buffer), which indicate that the upper mantle as well as the mantle/crust transition zone below the rift is at least partially oxidized. The ilmenite macrocrysts were transported from the source region to the surface by explosive alkali-basalt magmas, as implied by the presence of basaltic-pipe breccias in close vicinity to some placer deposits. 相似文献
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在地球内部的大部分区域地震体波的传播是线弹性过程,仅在震源周围区域由于波的辐射和传播效应可能导致非线性。本研究主要涉及对非线性过程占优势区域的尺度估计。 相似文献
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Jaromir Kolejka 《The Cartographic journal》2020,57(1):28-42
ABSTRACTThis paper presents the results of the analysis of more than 150 different printed newspaper weather forecasting maps, representing 91 global, national, regional and local daily news periodicals from 33 countries in 4 continents. The classification attention focused both on the character of the localizing background layer of the analysed maps as well as on the meteorological thematic layer. The results identify 12 types of background localizing maps and 47 used types of presentation of meteorological forecast information, only 19 of which were used repeatedly in more than one newspaper. All the findings were documented on comparable cartographic models. Conclusions suitable for practical applications are demonstrated in the discussion. 相似文献