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Showing 1 to 14 of 14 for “"ultrahigh-pressure"”.
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Temporal and petrological constraints of ultrahigh-pressure metamorphism and exhumation of crustal material from mantle depths to Earth's surface: Insights from a large and small ultrahigh-pressure terrane
Ultrahigh-pressure (UHP) terranes expose continental material that has subducted to mantle depths and then returned to Earth's surface. These terranes typically consist mainly of migmatitic host ortho- and paragneiss, with minor (~5%) layers and lenses of UHP eclogite; at least twenty terranes have …
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Design, testing, and utilization of a spherical shock-recovery system to investigate material response to ultrahigh pressure
… extensively in the study of materials under high pressure. However, a three-dimensional system capable of substantially higher pressure with the capability of full sample recovery would add a new dimension to the analysis of materials exposed to ultra-high shock pressure. In this thesis, an …
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Geochemistry, Geothermobarometry and Geochronology of High-Pressure Granulites and Implications for the Exhumation History of Ultrahigh-Pressure Terranes: Dulan, Western China
<p>The Dulan ultrahigh-pressure (UHP) rocks of the North Qaidam terrane, Western China, represent continental crust that has been subducted ~100 km during continental collision. Adjacent granulites representing burial to ~50 km could either be overprinted eclogites or a separate …
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Tracking multistage deformation within an ultrahigh-pressure terrane: zircon and monazite microstructures and petrochronology from shear zones of the Western Gneiss Region, Norway
… through time andby overprinting of the pressure-temperature-time-deformation (P-T-t-d) record byyounger orogenic events. The Western Gneiss Region (WGR), Norway, is an ultrahigh-pressure (UHP) terrane that was variably deformed during Proterozoic and (U)HPOrdovician-Devonian Caledonian …
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Estimating the thickness of an ultrahigh-pressure (UHP) terrane: insights from phase equilibria modelling and Zr-in-rutile thermometry, Dulan area, North Qaidam terrane, China
… early retrogression, at ~23 kbar and <750 °C. Pressure fluctuations in the P-T path suggest that the Dulan area experienced subduction and exhumation cycles. Our results indicate that the Dulan area experienced slow heating, and a protracted eclogite-facies metamorphism (~38 Myr). Comparing …
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Structural constraints on the exhumation of the Tso Morari Dome, NW Himalaya
… one of only two localities in the Himalaya where ultrahigh-pressure rocks have been found, the culmination offers important insights into the orogenic processes responsible for exhumation of subducted continental crust. New, 1:50,000 scale geologic mapping and structural analysis in the Tso Morari …
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Measuring Kinetic Performance of Monolithic and Fused-Core Columns Using Packed-Capillary Liquid-, Ultrahigh-Performance- and Supercritical Fluid Chromatography
<p>The high temperature and pressure capabilities of the newest LC instruments and the improvements in column technology that resulted in small particle columns and new morphologies like fused-core and monolithic columns imposed the need for methods that enable the selection of chromatographic …
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Capillary Liquid Chromatography Using Micro Size Particles
… chromatography (LC). However, due to the large pressure drop caused by small particles, conventional LC pumping systems cannot satisfy the pressure requirements needed to drive the mobile phase through the column. Use of ultrahigh pressure, elevated temperature, or both can overcome these …
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Metamorphic P-T Path and Multiple Fluid Events During Burial and Exhumation of the Tso Morari UHP Terrane, NW Himalaya
… within the Himalayan orogenic belt underwent ultrahigh-pressure (UHP) coesite-eclogite metamorphism due to northward subduction of the Indian continent under the Eurasian continent during the early Eocene. In this study we optimized a best protocol for thermodynamically modelling …
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Fluid Release During Eclogite Formation, North Qaidam Terrane, Western China
Ultrahigh-pressure (UHP, depths ≳100 km) eclogite samples from the Dulan area of the North Qaidam Terrane, western China, preserve evidence of fluid release along a prograde pressure-temperature (P-T) path. Eclogite sample D126A, Grt + Omp + Qtz + Zo + Amp + Phe + minor Rt + Hem, contains garnet …
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Rapid separation of biologically important low molecular weight compounds by microchip electrophoresis and ultra-fast performance liquid chromatography
… compounds by microchip electrophoresis and ultrahigh liquid chromatography. Chapter 1 introduces the theory and principles behind capillary electrophoresis separation. An overview of the history, different modes and detection techniques coupled to CE is provided. The advantages of microchip …
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Applying Garnet and Zircon REE Linkages to Determine Timing of P-T Conditions and Tectonic Implications for UHP Eclogites and HP Granulites, Dulan UHP Terrane, China
<p>The Dulan ultrahigh-pressure (UHP) terrane in western China hosts rocks that record continental collision, however; the timing of peak P-T conditions in UHP eclogites and HP granulites, and the tectonic significance of their spatial relationship within the Dulan UHP terrane are not well …
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Investigation of Novel Microseparation Techniques
Ultrahigh pressure liquid chromatography (UHPLC) makes it possible to use very small particles (< 2 µm) as packing materials to provide high column efficiencies. Results from a careful comparison of small porous and nonporous particles show that when the particle size is small enough (< 2 µm), both …
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Applications of Elastic Modeling, Thermobarometry, and Thermal History Modeling to (Ultra)high-Pressure Metamorphic Rocks
… metamorphic cycle. (Ultra)high-pressure ((U)HP) metamorphic rocks, such as blueschists and eclogites, are formed during metamorphism of subducted crust and sediments along relatively cold geothermal gradients. (U)HP metamorphic rocks may be incorporated into the subduction zone …