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Showing 1 to 20 of 49 for “"P-T conditions"”.
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Carbon dioxide (CO2) sorption to Na-rich montmorillonite at Carbon Capture, Utilization and Storage (CCUS) P-T conditions in saline formations
… CO2 in geologic formations in perpetuity. At PT conditions relevant to CCUS, CO2 is less dense than the pre-existing brine in the formation, and the more buoyant CO2 will migrate to the top of the formation where it will be in contact with cap rock. A typical cap rock is clay-rich shale, and …
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Spatial and Temporal Variations in Composition and P-T Conditions of Ore-Forming Fluids Along Structures Controlling Unconformity-Related Uranium Deposits in the Athatbasca Basin, Saskatchewan
… of composition and pressure-temperature conditions of ore-forming fluids along two major URU-controlling structures, the Patterson Lake corridor (PLC) in the southwestern margin of the basin and the P2 fault in McArthur River area in the eastern Athabasca Basin. The results provide new …
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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
… 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 understood. This study, (1) evaluates rare earth element (REE) equilibrium between garnet and …
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Petrology of the Taconian-Acadian Overlap Zone, Hartland Belt, Western Connecticut
… rims equilibrated with matrix minerals at P-T conditions that are consistent with an Acadian (Devonian) metamorphic field gradient for this area. P-T conditions were calculated by simultaneously solving for a geothermometer and a geothermobarometer in low-variance assemblages. All of the …
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Elasticity of single-crystal iron-bearing pyrope to 20 GPa and 750 K
… at relevant high pressure-temperature (P-T) conditions are crucial for understanding the composition and seismic velocity structures of the region. In this study, we have measured the single-crystal elasticity of natural Fe-bearing pyrope, Mg2.04Fe0.74Ca0.16Mn0.05Al2Si3O12, using in situ …
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Investigations of Trace Element Titanium in Silica Minerals
… a wide range of pressure (P) and temperature (T) conditions; therefore, quartz is an excellent mineral to target for thermobarometric uses. Thermobarometry is the quantitative determination of the pressure (baro-) and temperature (thermo-) conditions at which a natural rock sample reached chemical …
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Caratterizzazione geo-petrografica, petrologica e geochimica di rocce anatettiche del nord Sardegna
… pseudosections have been used to model the P-T conditions of anatexis on the basis of the melt volume (%) of melt, Si/Al and Na/K molar ratios, modal content of garnet and Si content in metamorphic white mica. Further pseudosections have been calculated for the average composition of leucosomes …
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Geological applications of synthetic fluid inclusions
… approximated by the NaCl-KCl-H₂O system. P-T conditions inferred from fluid inclusions in metamorphic rocks often disagree with values predicted from mineral equilibria calculations suggesting that inclusions formed during early stages of regional metamorphism continue to re-equilibrate during …
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INTO THE STRUCTURE OF THE PERMIAN DEEP CONTINENTAL CRUST: A MULTISCALE APPROACH TO RECONSTRUCT MIGMATIZATION IN THE VALPELLINE SERIES (DENT BLANCHE TECTONIC SYSTEM, WESTERN ITALIAN ALPS)
… interaction processes during deformation. P–T conditions of migmatization in the Valpelline Series, recorded in different lithologies, are contrasting. Black amphibolite and orthopyroxene-migmatitic gneiss show peak conditions comprised between 800–900 °C and 0.8–1.0 GPa, while …
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From the Appalachians to the Alps: Constraints on the Timing, Duration, and Conditions of Metamorphism at Convergent Margins
… timing, duration, and pressure-temperature (P-T) conditions of metamorphism provide a direct record of the physical and chemical evolution of the crust and inform our knowledge and understanding of plate tectonics. The characteristic timescales and length-scales of metamorphism vary by orders of …
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Mineral equilibria constraints on open-system melting and consequences of melt loss in metabasic rocks
… and eclogite compositions under orogenic P-T conditions in the crust.
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Garnet-biotite thermometry, garnet-aluminum silicate-silica-plagioclase barometry, and Emp monazite geochronology of the early Proterozoic Ivanpah Mountains, eastern Mojave Desert, Se California
… event during the Early Proterozoic. Peak P-T conditions, using garnet-Al2SiO5-silica-plagioclase barometry and garnet-biotite thermometry, were ∼4.0kb and >700°C, respectively. Peak metamorphic-T's were recorded by the largest garnet studied; Electron Microprobe Analysis on monazite, …
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The petrology of the Kielder sulphide bodies and their wall rocks : district of Prieska, N. Cape, South Africa
… east to west, with the K3 area suffering P-T conditions of 695⁰ C and 6. 0 Kbars; the Kl area 686⁰ C and 5.8 Kbars and the K6 area 590⁰ C and 5.6 Kbars.
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Mineral Equilibrium Constraints on the Feasibility of Diffusively-Fluxed Melting in the Continental Crust
… equilibrium modelling to determine the P–T conditions, melt volumes, melting reactions and viable fluid sources reveal that water-present melting in all target lithologies is confined to the wet solidus and does not extend to temperatures higher than 700–710 ◦C. Melting at suprasolidus …
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Tectonometamorphic evolution of Medium-P granulites of the Namaqua Metamorphic Province at the Gordonia Subprovince marginal zone, southern Namibia
… the hangingwall constrains peak metamorphic P-T conditions of ~5.2-5.9 kbar and ~790-815°C which are correlated to a monazite growth event at c. 1262-1184 Ma. Sheared pelitic granulites constrain the P-T conditions for early stage shearing in the LFRTZ to ~2.8-5.0 kbar and ~640-785°C which likely …
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Advances in Subduction Zone Processes
… hotter subduction zones have more favorable P-T conditions in which to facilitate decarbonation than colder subduction, the extent of decarbonation is largely dependent on the availability of fluid from the dehydration of underlying serpentine. The third chapter constrains the P-T-t paths of …
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Geochemical Constraints of Porphyry Cu Deposits-Forming Magmas in Sonora, Mexico
… by variations in pressure-temperature (P–T) conditions, redox state, and volatile content during magmatic evolution (Richards, 2003; Audétat et al., 2008). These factors influence the capacity of magmas to concentrate and transport metals such as Cu. This thesis investigates the geochemical …
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Using Metamorphic Textures to Infer Deformation and Thermodynamic Histories
… are commonly used to determine P-T conditions in metamorphic rock assemblages. However, the actual process of porphyroblast nucleation is still poorly understood and garnet growth may occur at different conditions than those predicted by equilibrium thermodynamics. It is typically …
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S-wave velocity structure beneath the Kaapvaal Craton from surface-wave inversions compared with estimates from mantle xenoliths
… to obtain the equilibrium P-T conditions of the cratonic mantle to about 180km depth [James et al 2004]. Seismic velocity-depth and density-depth profiles calculated on the basis of these P-T data and the mineral modes of the xenoliths are used to produce theoretical …
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Density, magnetic properties and sound velocities of iron-rich materials at high temperature and high pressure
… core and the density of pure iron at relevant conditions. The nature and abundance of light element(s) are under debate, yet they are fundamental in understanding the formation and evolution of the Earth’s core. Carbon has been considered a possible major light element candidate, besides …
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