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41.
Morteza Khalatbari-Jafari Thierry Juteau Hervé Bellon Hashem Emami 《Comptes Rendus Geoscience》2003,335(12):917-929
New field and laboratory studies on the ophiolite of Khoy (northwestern corner of Iran) lead to the discovery that there are not one, but two ophiolitic complexes in the Khoy area: (1) an old, poly-metamorphic ophiolite, whose oldest metamorphic amphiboles yielded a Lower Jurassic apparent 40K–40Ar age, and whose primary magmatic age should logically be pre-Jurassic (Upper-Triassic?); (2) a younger non metamorphic ophiolite of well dated Upper Cretaceous age. To cite this article: M. Khalatbari-Jafari et al., C. R. Geoscience 335 (2003). 相似文献
42.
The aim of this paper is to develop a methodology for identifying various dimensions of the spatial configuration of urban systems in Iran from an interaction perspective. Through the provision of empirical evidence of different types of flows of people including air passenger flows, passenger flows by bus and car, this paper compares the resulting spatial constellations of these flows through the innovative use of indices to systematically describe and measure five dimensions of an urban system’s spatial configuration that include: (1) centrality and dominance of vertices, (2) network cohesion, (3) network strength, (4) network symmetry, and (5) communities and levels. The findings show that although the spatial configurations of different flows are not the same, all were characterized by having a significant distance within a polycentric urban system due to the primacy of the Tehran metropolis. In regard to passenger flows by car and bus, it was found that for various functional regions, there was a balanced distribution of centrality and urban hierarchy evident in Iran. By contrast, air passenger flows were not able to determine centrality within a national urban hierarchy because of the limited distribution of centers for air travel in Iran at higher levels of spatial organization. 相似文献