Further rock magnetic and chronostratigraphic results on reversal excursions during the last 50 ka as derived from northern high latitudes and discrepancies in precise AMS ¹⁴C dating     

Norbert R. Nowaczyk  Martin Antonow  Jochen Knies  Robert F. Spielhagen 《Geophysical Journal International》2003,155(3):1065-1080

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Regime shifts in the marine environment: the scientific basis and political context   总被引：1，自引：0，他引：1  

Kraberg AC  Wasmund N  Vanaverbeke J  Schiedek D  Wiltshire KH  Mieszkowska N 《Marine pollution bulletin》2011,62(1):7-20

Regime shifts in the marine environment have recently received much attention. To date, however, few large-scale meta-analyses have been carried out due to insufficient data coverage and integration between sustained observational datasets because of diverse methodologies used in data collection, recording and archival. Here we review the available data on regime shifts globally, followed by a review of current and planned policies with relevance to regime shifts.We then focus on the North and Baltic Seas, providing examples of existing efforts for data integration in the MarBEF Network of Excellence. Existing gaps in data coverage are identified, and the added value from meta-analyses of multiple datasets demonstrated using examples from the MarBEF integrated data project LargeNet. We discuss whether these efforts are addressing current policy needs and close with recommendations for future integrated data networks to increase our ability to understand, identify and predict recent and future regime shifts.  相似文献   

New findings on the tectono-metamorphic history of the western Rhenish Massif (Germany) by K–Ar dating of metasedimentary illite     

Rolf Nierhoff  Norbert Clauer  Gerhard Spaeth 《Journal of Geodynamics》2011

Metapelites, clay-rich sandstones and volcanics from Cambrian, Ordovician and Lower Devonian strata of the western Rhenish Massif underwent a complex regional Variscan tectono-thermal evolution, as shown by mineralogical and K–Ar isotopic analyses of the illite to mica components from three NW-SE transects. The metamorphic degree extended from an anchimetamorphic to an epimetamorphic intensity during two major episodes of illite crystallization at 328 ± 6 and 282 ± 12 Ma. A further late orogenic or post-orogenic extensional activity could also be detected, but not precisely, around 270 Ma, probably recorded by the precipitation of illite in new or reactivated extensional faults with upward moving heat flows.  相似文献   

Reply to the comment of Mitchell et al. (2010) on “Formation of Thetis Deep metal-rich sediments in the absence of brines,Red Sea” by Pierret et al. (2010)     

Marie-Claire Pierret  Norbert Clauer 《Journal of Geochemical Exploration》2011

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Expected damage from displacement of slow-moving slides   总被引：10，自引：7，他引：3  

Mohamed Farouk Mansour  Norbert R. Morgenstern  C. Derek Martin 《Landslides》2011,8(1):117-131

Facilities such as buildings, highways, railways, bridges, dams and pipelines often are built on natural slopes where the risk of landslides is not low. The vulnerability of these facilities to slow-moving slides has sometimes been underestimated, although the velocity of some classes of slow slides is uncontrollable. More than 50 cases of slow slides were compiled from the literature for this study. Some statistics about the movement trigger(s), the methods used to measure displacement, the material forming the rupture surface and the type of the vulnerable facilities are presented. It is shown that the expected degree of damage to urban settlements, highways, bridges and dams can be related to the slide velocity or accumulating displacement. Buildings and residential houses may tolerate higher slide velocities and total displacements than other facilities before experiencing serious damage. Movements as low as 100 mm may severely damage bridges, but such low rates may cause only moderate damage to urban communities. The relationship between movement and the expected extent of damage should be useful to geotechnical engineers who deal with different classes of slow slides and will help in the choice of appropriate mitigation measures based on preliminary estimates of movement rates.  相似文献   

A heat flow and physical properties package for the surface of Mercury     

Tilman Spohn  Andrew J. Ball  Karsten Seiferlin  Vera Conzelmann  Axel Hagermann  Norbert I. mle  Günter Kargl 《Planetary and Space Science》2001,49(14-15)

European Space Agencies fifth cornerstone mission BepiColombo includes a ‘Surface Element’ to land a scientific payload on the surface of Mercury. The current strawman payload includes a heat flow and physical properties package (HP³), focussing on key thermal and mechanical properties of the near-surface material (down to a depth of 2–5 m) and the measurement of heat flow from Mercury's interior, an important constraining parameter for models of the planet's interior and evolution. We present here an overview of the HP³ experiment package and its possible accommodation in a self-inserting ‘mole’ device. A mole is considered to be the most appropriate deployment method for HP³, at least in the currently-assumed case of an airbag-assisted soft landing architecture for the Mercury Surface Element.  相似文献   

GALACSI – The ground layer adaptive optics system for MUSE     

Remko Stuik  Roland Bacon  Ralf Conzelmann  Bernard Delabre  Enrico Fedrigo  Norbert Hubin  Miska Le Louarn  Stefan Strbele 《New Astronomy Reviews》2006,49(10-12):618

MUSE, the Multi-Unit Spectroscopic Explorer, is an adaptive optics (AO)-assisted Integral Field Spectrograph, currently in the Preliminary Design Phase as a second generation instrument for the VLT. MUSE will feature two modes, each with an associated AO mode. The first mode is the wide field mode, mainly aiming at the study of high redshift galaxies. For this mode, the AO system has to deliver an improvement of at least a factor of two over the full 1′ × 1′ field of view. The second mode, the narrow field mode, aims at the high-resolution spectroscopy of nearby extended objects, for example, galaxies and globular clusters. For this mode, the AO system will have to deliver near-diffraction limited performance over a small field of view. In this paper, we discuss the trade-offs in the current design of GALACSI – the MUSE AO system – and illustrate with a number of simulations the expected performance in the wide- and narrow field modes.  相似文献   

Eocambrian—Cambrian palaeomagnetism of the Armorican Massif, France     

Jonathan T. Hagstrum  Rob Van der  Voo Bernard Auvray  Norbert Bonhommet 《Geophysical Journal International》1980,61(3):489-517

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On the application of combined geoelectric weighted inversion in environmental exploration     

Ákos Gyulai  Mátyás Krisztián Baracza  Norbert Péter Szabó 《Environmental Earth Sciences》2014,71(1):383-392

Geophysical surveying methods are of great importance in environmental exploration. Inversion-based data processing methods are applied for the determination of geometrical and physical parameters of the target model. The use of this geoelectric inversion method is advantageous in environmental research where highly reliable information with large spatial resolution is required. The 2D combined geoelectric inversion (CGI) method performs more accurate parameter estimation than conventional 1D single inversion methods by efficiently decreasing the number of unknowns of the inverse problem (single means that data sets of individual vertical electric sounding stations are inverted separately). The quality improvement in parameter space is demonstrated by comparing the traditional 1D inversion procedure with a 2D series expansion-based inversion technique. The CGI method was further developed by weighting individual direct current geoelectric data sets automatically in order to improve inversion results. The new algorithm was named combined geoelectric weighted inversion, which extracts the solution by a special weighted least squares technique. It is shown that the new inversion methodology is applicable to resolve near-surface structures such as rapidly varying layer boundaries, laterally inhomogeneous formations and pinch-outs.  相似文献   

Debris flow impact assessment caused by 14 April 2012 rainfall along the Al-Hada Highway,Kingdom of Saudi Arabia using high-resolution satellite imagery   总被引：1，自引：0，他引：1  

Ahmed M. Youssef  Biswajeet Pradhan  Norbert H. Maerz 《Arabian Journal of Geosciences》2014,7(7):2591-2601

The Al-Hada highway that descends towards the west of the city of At-Taif is a major connecting highway in the western part of the Kingdom of Saudi Arabia. It is one of the series of descending roads connecting the holy city of Makkah and the city of Jeddah with the city of At-Taif and the cities farther south along the escarpment. The length of the Al-Hada highways is about 22 km. The Al-Hada highway has been historically exposed to landslides and other geohazards since the day it was opened to public some 60 years ago. The road has been reconstructed and many slope instabilities have been remediated and the road has been expanded to two lanes in each direction. Heavy rainfalls occurred on the 14th of April 2012 in the province of At-Taif, causing huge debris flows in two places along the Al-Hada highway. As a result of that, these debris flows closed all four lanes of the highway for 2 weeks in order to remove the debris. The current research deals with mapping of all debris flows along Al-Hada highway and determining their volumes and their impact on the road. Finally, suitable solutions have been suggested to address these critical sites to minimize and/or avoid the debris flow hazards in the future.  相似文献