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31.
Dozent Dr. Werner Ernst 《International Journal of Earth Sciences》1966,55(1):21-29
Zusammenfassung Die Bor-Gehalte des paralischen Oberkarbons sind vorwiegend von der ursprünglichen Salinität im Ablagerungsgebiet abhängig. Daneben scheint das Klima eine Auswirkung zu haben, die sich durch die Erhöhung der Bor-Gehalte vom Westfal B an und im Rotliegenden, Keuper und Tertiär bemerkbar macht.
The boron contents of the paralic Upper Carboniferous depend principally on the original salinity in the area of sedimentation. Besides, the climate appears to have an effect that manifests itself by increase in the boron contents from the Westphalian B on and in the Rotliegendes, Keuper and tertiary.
Résumé Les teneurs en bore du Carbonifère supérieur pralique dépendent avant tout de la salinité originale de la région de sédimentation. Par ailleurs, le climat paraît avoir eu une influence qui se traduit par un accroissement des teneurs en bore dans le Westphalien B, le Rotliegende, le Keuper et le Tertiaire.
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32.
Prof. Dr. Ernst H. Ackermann 《International Journal of Earth Sciences》1965,54(2):796-812
The rocks of the cratonic foreland extend underneath many orogens, where they are subjected to “regeneration” during the geosynclinal phase and to superimposed structures during the folding of the orogen. Such structural and metamorphic alterations are now exposed in the “Sockelstockwerk” of certain orogenic belts in Africa, America, Australia and Europe. In this deep level, originally situated between the bottom of the geosyncline and the migmatite stockwerk, the following zones have been observed along the total length of the orogenic belt: border zone along the margin of the cratonic foreland: broad belt with superimposed structures of two (ore more) different orogenic deformations; main vergency fan, marking the central axis of the orogen. This fan often is a lineament with deep roots and a structure of continental importance. 相似文献
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Johannes Bouman Sietse Rispens Thomas Gruber Radboud Koop Ernst Schrama Pieter Visser Carl Christian Tscherning Martin Veicherts 《Journal of Geodesy》2009,83(7):659-678
One of the products derived from the gravity field and steady-state ocean circulation explorer (GOCE) observations are the
gravity gradients. These gravity gradients are provided in the gradiometer reference frame (GRF) and are calibrated in-flight
using satellite shaking and star sensor data. To use these gravity gradients for application in Earth scienes and gravity
field analysis, additional preprocessing needs to be done, including corrections for temporal gravity field signals to isolate
the static gravity field part, screening for outliers, calibration by comparison with existing external gravity field information
and error assessment. The temporal gravity gradient corrections consist of tidal and nontidal corrections. These are all generally
below the gravity gradient error level, which is predicted to show a 1/f behaviour for low frequencies. In the outlier detection, the 1/f error is compensated for by subtracting a local median from the data, while the data error is assessed using the median absolute
deviation. The local median acts as a high-pass filter and it is robust as is the median absolute deviation. Three different
methods have been implemented for the calibration of the gravity gradients. All three methods use a high-pass filter to compensate
for the 1/f gravity gradient error. The baseline method uses state-of-the-art global gravity field models and the most accurate results
are obtained if star sensor misalignments are estimated along with the calibration parameters. A second calibration method
uses GOCE GPS data to estimate a low-degree gravity field model as well as gravity gradient scale factors. Both methods allow
to estimate gravity gradient scale factors down to the 10−3 level. The third calibration method uses high accurate terrestrial gravity data in selected regions to validate the gravity
gradient scale factors, focussing on the measurement band. Gravity gradient scale factors may be estimated down to the 10−2 level with this method. 相似文献
36.
Ernst Fischer 《Astrophysics and Space Science》2010,325(1):69-74
Homogeneous solutions in the framework of general relativity form the basis to understand the properties of gravitation on
global scale. Presently favoured models describe the evolution of the universe by an expansion of space, governed by a scale
function, which depends on a global time parameter. Dropping the restriction that a global time parameter exists, and instead
assuming that the time scale depends on spatial distance, leads to static solutions, which exhibit no singularities, need
no unobserved dark energy and which can explain the cosmological red shift without expansion. In contrast to the expanding
world model energy is globally conserved. Observations of high energy emission and absorption from the intergalactic medium,
which can scarcely be understood in the ‘concordance model’, find a natural explanation. 相似文献
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Roman Skála Jaromír Ulrych Lukáš Ackerman Emil Jelínek Jaroslav Dostál Ernst Hegner Zdeněk Řanda 《International Journal of Earth Sciences》2014,103(5):1233-1262
The ?eské st?edoho?í Mts. is the dominant volcanic center of the Oh?e (Eger) rift zone. It hosts the Roztoky Intrusive Complex (RIC), which is made up of a caldera vent and intrusions of 33–28-Ma-old hypabyssal bodies of essexite–monzodiorite–sodalite syenite series accompanied by a radially oriented 30–25-Ma-old dike swarm comprising about 1,000 dikes. The hypabyssal rocks are mildly alkaline mostly foid-bearing types of mafic to intermediate compositions. The dike swarm consists of chemically mildly alkaline and rare strongly alkaline rocks (tinguaites). The geochemical signatures of the mildly alkaline hypabyssal and associated dike rocks of the RIC are consistent with HIMU mantle sources and contributions from lithospheric mantle. The compositional variations of essexite and monzodiorite can be best explained by fractional crystallization of parent magma without significant contributions of crustal material. On the other hand, the composition of monzosyenite, leuco-monzodiorite and sodalite syenite reflects fractional crystallization coupled with variable degrees of crustal assimilation. It is suggested that the parent magmas in the Oh?e rift were produced by an adiabatic decompression melting of ambient upper mantle in response to lithospheric extension associated with the Alpine Orogeny. 相似文献
40.
María Eugenia Varela Gero Kurat Ernst Zinner Peter Hoppe Theodoros Ntaflos Mikhail A. Nazarov 《Meteoritics & planetary science》2005,40(3):409-430
Abstract— D'Orbigny is an exceptional angrite. Chemically, it resembles other angrites such as Asuka‐881371, Sahara 99555, Lewis Cliff (LEW) 87051, and LEW 86010, but its structure and texture are peculiar. It has a compact and porous lithology, abundant glasses, augite‐bearing druses, and chemical and mineralogical properties that are highly unusual for igneous rocks. Our previous studies led us to a new view on angrites: they can possibly be considered as CAIs that grew to larger sizes than the ones we know from carbonaceous chondrites. Thus, angrites may bear a record of rare and special conditions in some part of the early solar nebula. Here we report trace element contents of D'Orbigny phases. Trace element data were obtained from both the porous and the compact part of this meteorite. We have confronted our results with the popular igneous genetic model. According to this model, if all phases of D'Orbigny crystallized from the same system, as an igneous origin implies, a record of this genesis should be expressed in the distribution of trace elements among early and late phases. Our results show that the trace element distribution of the two contemporaneous phases olivine and plagioclase, which form the backbone of the rock, seem to require liquids of different composition. Abundances of highly incompatible elements in all olivines, including the megacrysts, indicate disequilibrium with the bulk rock and suggest liquids very rich in these elements (>10,000 x CI), which is much richer than any fractional crystallization could possibly produce. In addition, trace element contents of late phases are incompatible with formation from the bulk system's residual melt. These results add additional severe constraints to the many conflicts that existed previously between an igneous model for the origin of angrites and the mineralogical and chemical observations. This new trace element content data, reported here, corroborate our previous results based on the shape, structure, mineralogy, chemical, and isotopic data of the whole meteorite, as well as on a petrographic and chemical composition study of all types of glasses and give strength to a new genetic model that postulates that D'Orbigny (and possibly all angrites) could have formed in the solar nebula under changing redox conditions, more akin to chondritic constituents (e.g., CAIs) than to planetary differentiated rock. 相似文献