Dendrochronologie     

Bruno Huber 《International Journal of Earth Sciences》1960,49(1):120-131

Zusammenfassung Die Dendrochronologie arbeitet mit der Jahresschichtung des Holzes. Der Zuwachs gleichzeitig wachsender Hölzer ist ähnlich. Diese Forschungsrichtung braucht viel Material zur Herstellung typischer Mittelkurven. Mit Hilfe der Überbrückungsmethode kommt man örtlich sehr weit zurück. Schwierigkeiten liegen in der gesetzmäßigen Abnahme der Ähnlichkeit von Jahresringkurven mit der Entfernung voneinander. Neben einer absoluten Chronologie sind in Deutschland relative Chronologien aus Jungsteinzeit und Bronzezeit erarbeitet worden. Die Dendrochronologie kann gewisse Aussagen über Klimaschwankungen machen.  相似文献   

Über die Messung von Massensehwächungskoeffizienten bei der Phasenanalyse mit dem Zählrohrgoniometer     

Dr. Bruno Brehler 《Contributions to Mineralogy and Petrology》1957,6(1):52-58

Zusammenfassung Es wird ein Verfahren angegeben, um bei der röntgenographischen Gemischanalyse mit dem Zählrohrgoniometer, dann wenn die Gefahr von Textureffekten nicht besteht, die Intensitäten der Analysenlinien und den Massenschäwachungskoeffizienten in demselben Präparat messen zu können; dazu wird in den Boden des Präparatträgers eine Einkristallplatte eingekittet und die Schwächung gemessen, die ein Reflex der Kristallplatte durch Einbringen der Präparatsubstanz erfährt.  相似文献   

Correcting superconducting gravity time-series using rainfall modelling at the Vienna and Membach stations and application to Earth tide analysis     

Bruno Meurers  Michel Van Camp  Toon Petermans 《Journal of Geodesy》2007,81(11):703-712

We demonstrate the possibility to improve the signal-to-noise ratio of superconducting gravity time-series by correcting for local hydrological effects. Short-term atmospheric events associated with heavy rain induce step-like gravity signals that deteriorate the frequency spectrum estimates. Based on 4D modeling constrained by high temporal resolution rain gauge data, rainfall admittances for the Vienna and Membach superconducting gravity stations are calculated. This allows routine correction for Newtonian rain water effects, which reduces the standard deviation of residuals after tidal parameter adjustment by 10%. It also improves the correction of steps of instrumental origin when they coincide with step-like water mass signals.  相似文献   

Validation of climate model output using Bayesian statistical methods     

Mark A. Snyder  Bruno Sansó  Lisa C. Sloan 《Climatic change》2007,83(4):457-476

The growing interest in and emphasis on high spatial resolution estimates of future climate has demonstrated the need to apply regional climate models (RCMs) to that problem. As a consequence, the need for validation of these models, an assessment of how well an RCM reproduces a known climate, has also grown. Validation is often performed by comparing RCM output to gridded climate datasets and/or station data. The primary disadvantage of using gridded climate datasets is that the spatial resolution is almost always different and generally coarser than climate model output. We have used a Bayesian statistical model derived from observational data to validate RCM output. We used surface air temperature (SAT) data from 109 observational stations in California, all with records of approximately 50 years in length, and created a statistical model based on this data. The statistical model takes into account the elevation of the station, distance from coastline, and the NOAA climate region in which the station resides. Analysis indicates that the statistical model provides reliable estimates of the mean monthly SAT at any given station. In our method, the uncertainty in the estimates produced by the statistical model are directly determined by obtaining probability density functions for predicted SATs. This statistical model is then used to estimate average SATs corresponding to each of the climate model grid cells. These estimates are compared to the output of the RCM to assess how well the RCM matches the observed climate as defined by the statistical model. Overall, the match between the RCM output and the statistical model is good, with some deficiencies likely due in part to the representation of topography in the RCM.  相似文献   

Solar Coronal Plasma in Doppler Measurements     

Bruno Bertotti  Giacomo Giampieri 《Solar physics》1998,178(1):85-107

Doppler tracking of an interplanetary spacecraft near solar conjunction is strongly affected by the plasma in the solar corona, the main competitive contribution in measurements of the gravitational deflection of light rays. With the simultaneous availability of carriers in X band and K_a band for interplanetary communications, the plasma contribution to the corona can be accurately eliminated and measured. If, as in the Cassini mission, three different observables are available, this can be done in two ways: one deals with the total plasma content in the electric approximation, even in the ionosphere and interplanetary space; another is limited to the corona, but has access to subtler effects, like the magnetic correction to the refractive index. This technique will allow important progress in the radio investigation of the solar corona.  相似文献   

Numerical analysis of field-scale transport of bromacil     

David Russo  Inbar Tauber-Yasur  Asher Laufer  Bruno Yaron 《Advances in water resources》1998,21(8):1637

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Seismic study of the Mesozoic carbonate basement around Mt. Somma–Vesuvius, Italy     

Pier Paolo G. Bruno  Giuseppe Cippitelli  Antonio Rapolla 《Journal of Volcanology and Geothermal Research》1998,84(3-4)

Fifteen seismic reflection lines from AGIP surveys, in and around the Campanian Plain and Mt. Somma–Vesuvius (south Italy) have been interpreted. The attention has been focused to the horizon pertinent to the top of the Mesozoic carbonate sequence and the Quaternary faults dissecting it. As a matter of fact, both are very important elements for understanding the origin of the volcanic activity in the area, that often in the past, has been the topic of debates not supported by reliable data. In the study area, referring to the depth of the carbonate basement, comparison between the result achieved by the seismic prospecting and previous gravity studies has been made. It shows coherence in some areas but large discrepancy within others. Near the town of S. Anastasia, the gravity and seismic depth estimates differ as much as 1000 m or more. Furthermore, the seismic data show that the source of the greatest volcanic eruption in the area (the so-called ‘Campanian Ignimbrite') is probably not located in the Acerra depression, as suggested by other authors. A main NE–SW fault directed toward Vesuvius, considered as playing a primary role on volcanogenetic processes and previously recognised only offshore by marine seismic survey, has been now identified also inland using this new seismic information. The results presented here strengthen the hypothesis that Mt. Vesuvius is located at the crossing point of two regional Quaternary sets of fault heading NW–SE and NE–SW.  相似文献   

Lead-lead systematics,the “age of the Earth” and the chemical evolution of our planet in a new representation space     

Gérard Manhes  Claude J. Allègre  Bernard Dupré  Bruno Hamelin 《Earth and Planetary Science Letters》1979,44(1):91-104

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Geologische Problematik und Strukturanalyse Nikaraguas     

Prof. Dr. Bruno Engels 《International Journal of Earth Sciences》1965,54(2):758-795

The basement of northern Nicaragua is still a great problem stratigraphically. Enclosed tuffits (mainly basic, partly also intermediate to acid) appear of importance for both petrology and sedimentology. Not in the least they are guide horizons for a more accurate mapping. The vast regional distribution, commonly proved yet, suggests that the composition of the basement is considerably uniform and it seems that they do not belong to different periods and formations. Structurally the region is exceedingly complicated. The folding direction as regards plication and overthrusts is mainly to the North, but partly also to the East. Probably the “Totogalpa formation” (fanglomerates, conglomerates and sandstones, mainly reddish) which follows disconformably over the basement, already indicated, belongs to the sequence of tertiary tuffites, agglomerates, lavas etc. as they conformably form a formation of uniform composition. The relation of basement to lower Cretaceous (marine Albian; “Metapan”), which follows immediately to the south, is less clear. The lower Cretacious shows intensive and complicated folding at Siuna and it appears almost unmetamorphosed (? basement in a wider sense). The marine sediments (upper Cretacious - Miocene) of South Nicaragua are orogenetically only slightly efected (folding direction to E-N). To the North follows a thick serie of Tertiary and Quarternary volcanites (initially mainly submarinal, later on continental). Together with the NW/SE lineaments (Nicaragua depression, lines of volcanoes, coast line in the SW etc.) also NS directed ones clearly appear (coastline in the East). This direction can be found e. g. in the “granite ridge of Susucayan” and the accompanying faults in the vicinity. These latter structures may have taken an active part in the development of the flexured border of the Nicaraguan depression NW of Managua.  相似文献   

Über die Fazies des Hunsrückschiefers     

Bruno Engels 《International Journal of Earth Sciences》1956,45(1):143-150

Zusammenfassung Einleitend wird auf die vielfältige Problematik des Hunsrückschiefers hingewiesen. Hinsichtlich der Petro-Fazies ergibt sich ein Vorwalten der feinsandigen Komponente mit einem Feldspaltgehalt von durchschnittlich 10–13%. Die. Ergebnisse spektroskopischer und autoradiographischer Untersuchungen werden mitgeteilt. Die Mächtigkeit scheint in der SE-Eifel am größten zu sein und zum SE-Rand des Schiefergebirges hin ständig abzunehmen. Die Bio-Fazies wird vor allem hinsichtlich der sehr häufigen Fress-Bauten und Kriechspuren von Würmern behandelt, welche ein reiches Bodenleben im Hunsrückschiefer-Meer beweisen. Die Ansicht, daß der Hunsrückschiefer hauptsächlich aus Sedimenten eines Flach- und Wattenmeeres besteht, wurde bestätigt.  相似文献