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C. Vigny J. Chéry T. Duquesnoy F. Jouanne J. Ammann M. Anzidei J.-P. Avouac F. Barlier R. Bayer P. Briole E. Calais F. Cotton F. Duquenne K. L. Feigl G. Ferhat M. Flouzat J.-F. Gamond A. Geiger A. Harmel M. Kasser M. Laplanche M. Le Pape J. Martinod G. Ménard B. Meyer J.-C. Ruegg J.-M. Scheubel O. Scotti G. Vidal 《Journal of Geodesy》2002,76(2):63-76
The Western Alps are among the best studied collisional belts with both detailed structural mapping and also crustal geophysical
investigations such as the ECORS and EGT seismic profile. By contrast, the present-day kinematics of the belt is still largely
unknown due to small relative motions and the insufficient accuracy of the triangulation data. As a consequence, several tectonic
problems still remain to be solved, such as the amount of N–S convergence in the Occidental Alps, the repartition of the deformation
between the Alpine tectonic units, and the relation between deformation and rotation across the Alpine arc. In order to address
these problems, the GPS ALPES group, made up of French, Swiss and Italian research organizations, has achieved the first large-scale
GPS surveys of the Western Alps. More than 60 sites were surveyed in 1993 and 1998 with a minimum observation of 3 days at
each site. GPS data processing has been done by three independent teams using different software. The different solutions
have horizontal repeatabilities (N–E) of 4–7 mm in 1993 and 2–3 mm in 1998 and compare at the 3–5-mm level in position and
2-mm/yr level in velocity. A comparison of 1993 and 1998 coordinates shows that residual velocities of the GPS marks are generally
smaller than 2 mm/yr, precluding a detailed tectonic interpretation of the differential motions. However, these data seem
to suggest that the N–S compression of the Western Alps is quite mild (less than 2 mm/yr) compared to the global convergence
between the African and Eurasian plate (6 mm/yr). This implies that the shortening must be accomodated elsewhere by the deformation
of the Maghrebids and/or by rotations of Mediterranean microplates. Also, E–W velocity components analysis supports the idea
that E–W extension exists, as already suggested by recent structural and seismotectonic data interpretation.
Received: 27 November 2000 / Accepted: 17 September 2001 相似文献
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Vizvári Béla Golabi Mahmoud Nedjati Arman Gümüşbuğa Ferhat Izbirak Gokhan 《Natural Hazards》2019,99(1):571-597
Natural Hazards - In this study, a relief system for a large metropolitan city exposed to serious earthquakes is designed and a top-down approach is applied. Afflicted people’s states and... 相似文献
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The lower Mesozoic of the Traras mount starts with the so-called Red Series, which lays uncomformably on the folded and granitized Paleozoic basement. This series is overlain by Middle Liassic limestones. On the basis of its lower and upper limits and the lack of dating evidence, former authors attribute a Permian to lower Liassic (Sinemurian) age for this series. Palynological results allow to range it in the upper Triassic probably Norian-Rhetian. The Red Series is studied from five sections that depict important thickness and facies variations from southwest to the northeast, inferring the irregularities of the Hercynian erosional surface. In the Central Traras, this series shows over 130-m-thick micaceous sandy conglomeratic units, deposited within alluvial fans, where the bedrock source corresponds to granite of Nedroma or its equivalent. In the southern and eastern Traras, where the series’ thickness respectively does not exceed 30 m and averages 40–80 m, besides alluvial deposits issued from hercynian basement erosion, it exhibits volcanic evidences interbedded by lacustrine deposits. Vertical and spatial distribution depicts synsedimentary infilling of narrow elongated rift basins, typically half-grabens, bounded on one side by a normal fault or a series of normal faults trending NNE-SSW to NW-SE, inherited from the hercynian event. The study of tectonostratigraphic units permitted to put forward geodynamics of the infilling basins. 相似文献
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Mufide Banar Barbaros Murat Kose Aysun Ozkan Ilgın Poyraz Acar 《Environmental Geology》2009,58(5):1143-1144
This rebuttal was written in response to the rebuttal of the paper “choosing a municipal landfill site by analytic network
process” published in 2007 by M. Sagir. This study was conducted as an application for the landfill site selection in the
environmental engineering discipline. Since ANP was only the “instrument” used in our study, the details of this existing
methodology were referenced, and not presented, due to page limitations and to match the content of the journal. Responses
to M. Sagir’s comments are discussed within the body of this rebuttal. 相似文献
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zcan Gyrgy Less Mria Bldi-Beke Katalin Kollnyi Ferhat Acar 《Journal of Asian Earth Sciences》2009,34(6):740-760
The marine Oligo-Miocene units of western Taurides, deposited under different tectonic regimes (in Bey Da?lar? platform in foreland and coeval sequences in hinterland), were studied to establish a high-resolution biostratigraphic framework. Biometric study of the full spectrum of larger foraminifera in a regional scale allowed us correlating them with the shallow benthic zonation (SBZ) system introduced by [Cahuzac, B., Poignant, A., 1997. Essai de biozonation de l’Oligo-Miocène dans les bassins européens à l’aide des grands foraminifères néritiques. Bulletin de la Société géologique de France 168, 155–169], and to determine the ages of these sites on zonal precision for the first time. In correlating these assemblages to standard shallow benthic zones, planktonic data were also used whenever possible. Taxa, classified under the genera Nummulites, Miogypsina, Miolepidocyclina, Nephrolepidina, Eulepidina, Heterostegina, Operculina and Cycloclypeus (?) and their assemblages, closely resemble to the fauna described from European basins. These groups characterize the SBZ 22B to 25 zones referring to a time interval from early Chattian to Burdigalian. However, a main gap in late Chattian (SBZ 23) and in early part of the Aquitanian (SBZ 24) is also recorded in the platform succession. In the meantime, rare Eulepidina in the Burdigalian levels suggest a clear Indo-Pacific influence. Based on the discovery of early Chattian (SBZ 22B) deposits (previously mapped under Eocene/Miocene units), the Oligo-Miocene stratigraphy of the Bey Da?lar? platform is also revised. A more precise chronology for regional Miocene transgression is presented based on the miogypsinid evolutionary scale. 相似文献
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Adem Dogangun Ramazan Acar Halil Sezen Ramazan Livaoglu 《Bulletin of Earthquake Engineering》2008,6(3):505-517
Almost all historical minarets in Turkey were constructed using cut stone, masonry blocks or combination of these two materials.
The structural and geometrical properties of each masonry minaret, or slender tower structure, depend on many factors including
the structural knowledge and applications at the time of construction, experience of the architect or engineer, seismicity
of the region, and availability of construction materials in that area. Recent earthquakes in Turkey have shown that most
masonry minarets in high seismic regions are vulnerable to structural damage and collapse. In this study, in order to investigate
the dynamic behavior of historical unreinforced masonry minarets, three representative minarets with 20, 25, and 30 m height
were modeled and analyzed using two ground motions recorded during the 1999 Kocaeli and Duzce, Turkey earthquakes. The modal
analyses of the models have shown that the structural periods and the overall structural response are influenced by the minaret
height and spectral characteristics of the input motion. The dynamic displacement and axial stress time histories are computed
at the critical points on the minarets. During recent earthquakes, most minaret failures occurred above the base of the structure.
Consistent with the observed response, the largest stresses were calculated at the same location. 相似文献
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Zeynep Akbulut Samed Özdemir Hayrettin Acar Fevzi Karsli 《Journal of the Indian Society of Remote Sensing》2018,46(12):2057-2068
Automatic building extraction is an important topic for many applications such as urban planning, disaster management, 3D building modeling and updating GIS databases. Its approaches mainly depend on two data sources: light detection and ranging (LiDAR) point cloud and aerial imagery both of which have advantages and disadvantages of their own. In this study, in order to benefit from the advantages of each data sources, LiDAR and image data combined together. And then, the building boundaries were extracted with the automated active contour algorithm implemented in MATLAB. Active contour algorithm uses initial contour positions to segment an object in the image. Initial contour positions were detected without user interaction by a series of image enhancements, band ratio and morphological operations. Four test areas with varying building and background levels of detail were selected from ISPRS’s benchmark Vaihingen and Istanbul datasets. Vegetation and shadows were removed from all the datasets by band ratio to improve segmentation quality. Subsequently, LiDAR point cloud data was converted to raster format and added to the aerial imagery as an extra band. Resulting merged image and initial contour positions were given to the active contour algorithm to extract building boundaries. In order to compare the contribution of LiDAR to the proposed method, the boundaries of the buildings were extracted from the input image before and after adding LiDAR data to the image as a layer. Finally extracted building boundaries were smoothed by the Awrangjeb (Int J Remote Sen 37(3): 551–579. https://doi.org/10.1080/01431161.2015.1131868, 2016) boundary regularization algorithm. Correctness (Corr), completeness (Comp) and accuracy (Q) metrics were used to assess accuracy of segmented building boundaries by comparing extracted building boundaries with manually digitized building boundaries. Proposed approach shows the promising results with over 93% correctness, 92% completeness and 89% quality. 相似文献