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Strong Deformation (strong + deformation)
Selected AbstractsOrigin of metamorphic soles and their post-kinematic mafic dyke swarms in the Antalya and Lycian ophiolites, SW TurkeyGEOLOGICAL JOURNAL, Issue 3-4 2003Ö. Faruk Çeli Abstract The Antalya and Lycian ophiolites are situated in the western part of the Tauride belt (SW Turkey). Ophiolite-related metamorphic sole rocks in the Tauride belt are observed either at the base of the tectonites or in mélange units. Geochemical observations from the metamorphic sole rocks of Köyce,iz ophiolite indicate three different geochemical affinities: mid-ocean ridge basalt (MORB), island-arc tholeiite (IAT) and within-plate basalt (WPB) or seamount are present at the base of the Lycian ophiolites. The sole rocks of the ophiolite are made up of amphibolite, comprising mainly amphibole, pyroxene and plagioclase. Below the amphibolites are epidote-bearing rocks and, at the base, micaschists. The metamorphic sole below ophiolites exhibits an inverted metamorphic zonation. Very strong deformation within kyanite-garnet-bearing micaschists located far from the peridotites was observed, whereas the upper part of the metamorphic sole (near the contact with the peridotites) present relatively less deformation than the lower part. The metamorphic sole rocks of the Lycian ophiolite are cross-cut by some doleritic dykes with a typical greenschist facies mineral assemblage. However, while the metamorphic sole rocks exhibit well-developed lineation and foliation; the dykes lack such structures. Copyright © 2003 John Wiley & Sons, Ltd. [source] Basin- and Mountain-Building Dynamic Model of "Ramping-Detachment-Compression" in the West Kunlun-Southern Tarim Basin MarginACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 2 2008CUI Junwen Abstract: Analysis of the deformation structures in the West Kunlun-Tarim basin-range junction belt indicates that sediments in the southwestern Tarim depression were mainly derived from the West Kunlun Mountains and that with time the region of sedimentation extended progressively toward the north. Three north-underthrusting (subducting), steep-dipping, high-velocity zones (bodies) are recognized at depths, which correspond to the central West Kunlun junction belt (bounded by the Küda-Kaxtax fault on the north and Bulungkol-Kangxiwar fault on the south), Quanshuigou fault belt (whose eastward extension is the Jinshajiang fault belt) and Bangong Co-Nujiang fault belt. The geodynamic process of the basin-range junction belt generally proceeded as follows: centering around the magma source region (which largely corresponds with the Karatag terrane at the surface), the deep-seated material flowed and extended from below upward and to all sides, resulting in strong deformation (mainly extension) in the overlying lithosphere and even the upper mantle, appearance of extensional stress perpendicular to the strike of the orogenic belt in the thermal uplift region or at the top of the mantle diapir and localized thickening of the sedimentary cover (thermal subsidence in the upper crust). Three stages of the basin- and mountain-forming processes in the West Kunlun-southern Tarim basin margin may be summarized: (1) the stage of Late Jurassic-Early Cretaceous ramping-rapid uplift and rapid subsidence, when north-directed thrust propagation and south-directed intracontinental subduction, was the dominant mechanism for basin- and mountain-building processes; (2) the stage of Late Cretaceous-Paleogene deep-level detachment-slow uplift and homogeneous subsidence, when the dominant mechanism for the basin- and mountain-forming processes was detachment (subhorizontal north-directed deep-level ductile shear) and its resulting lateral propagation of deep material; and (3) the stage of Neogene-present compression-rapid uplift and strong subsidence, when the basin- and mountain-forming processes were simultaneously controlled by north-vergent thrust propagation and compression. The authors summarize the processes as the "ramping-detachment-compression basin- and mountain-forming dynamic model". The basin-range tectonics was initiated in the Late Jurassic, the Miocene-Pliocene were a major transition period for the basin- and mountain-forming mechanism and the terminal early Pleistocene tectonic movement in the main laid a foundation for the basin-and-mountain tectonic framework in the West Kunlun-southern Tarim basin margin. [source] Synthetic Explorations Towards Sterically Crowded 1,2,3-Substituted Bis(indenyl)zirconium(IV) DichloridesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 9 2005Andreas C. Möller Abstract The systematic synthesis of 1,3-dialkyl-substituted 2-silylindenes and their suitability as zirconocene ligands is discussed. Unexpected reactivities rendered a number of substitution patterns unfeasible, especially for alkyl groups other than methyl in 2-(trimethylsilyl)indene derivatives, and essentially for all derivatives of 2-(dimethylsilyl)indene. The syntheses of rac/meso -bis[1-methyl-2-(trimethylsilyl)indenyl]zirconium(IV) dichloride (12) and bis[1,3-dimethyl-2-(trimethylsilyl)indenyl]zirconium(IV) dichloride (13b) are described. The solid-state structure of the latter displays strong deformations within the ligand framework and an unusually large Cpcentroid -Zr,Cpcentroid angle. Both, 12/MAO and 13b/MAO, displayed ethene and ethene-co-1-hexene polymerization activity. Curiously, 13b/MAO shows an extraordinary monomer selectivity, which can be rationalized by means of DFT calculations on the active site. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Nanostructural properties of intraocular lenses (IOLs) , atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR) investigationsACTA OPHTHALMOLOGICA, Issue 2009E WYLEGALA Purpose To investigate and analyze surface of explanted intraocular lenses (IOL-s), by means of the Atomic Force Microscope (AFM) and Fourier transform infrared spectroscopy (FTIR). Methods Eight dry IOL-s (acrylic: SN60AT , 3 pieces, SA60AT , CZ70BD; silicone: CLRFLXC; "hard": AJPR,CP65T), and four hydrophilic acrylic IOL-s (AC-IOL and PC- IOL, both: naïve and removed during keratoplasty) were imaged (topography and phase) with AFM. AFM is used to investigate, at nanoscale, the surfaces' topography and some nanomechanical properties (eg. elasticity, hardness) of materials in medicine. The samples can be investigated in quasi-physiological conditions, usually no damaging preparation is required. For the acrylic and "hard" lenses the granular nanostructure is observed. The roughness of the lenses' surfaces can be then assessed. The silicone lens is soft: the forces of nanonewtons applied during imaging cause strong deformations of the material. Results Nanomechanical properties of PC-IOL lens are not uniform. This may be advantageous for its calcification: for the lens of the same type removed during keratoplasty strong calcification is observed. For SN60AT lens the influence of the application process (folding) on its nanostructure is tested. The observed structural nano-defects are permanent, they can occur during folding or can be caused by the used equipement. The similar nano-deformations are observed for the removed AC-IOL lens. Conclusion AFM and FTIR showed to be a high-resolution imaging tool for the scanning of surface IOL. [source] | ||||||||||