Here we determined the sound velocity and density of dolomite melt at upper mantle conditions using high-pressure experiments and theoretical simulations. The …Web
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In marble preparation, the dolomite were passed through the desired sieves (2.0 mm, 1.0 mm, 600 um, 150 um, and 75 um), while raw andalusite was dried, grounded and sieved with opening size of 75 um.Web
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(A) Sound velocity as a function of pressure for dolomite melt. Different markers correspond to different experimental runs: square-T2207, circle-T2208, upward-pointing triangle-T2261, downward ...Web
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Structural parameters have been refined using X-ray intensity data for a stoichiometric dolomite single crystal at room pressure and at 1.50, 2.90,3.70, and 4.69 …Web
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Dolomite-II. On compression at ambient temperature, the rhombohedral dolomite structure (Fig. 1 A) was observed up to 17 GPa, in line with other very recent …Web
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Here we report the first high-pressure experimental study on the density and sound velocity of a carbonate melt (dolomite composition, CaMg(CO 3) 2), as well as new FPMD simulation results on dolomite melt. Of all of the carbonate melt compositions, the dolomite composition is of primary interest for the upperWeb
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The high-pressure behaviour of dolomite was inves-tigated by Ross and Reeder (1992) (up to 4 GPa), Fiquet et al. (1994) (up to 11 GPa) and Hammouda et al. (2011) (up to 7GPa). High-pressure ...Web
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Structural and mechanical properties of dolomite rock under high pressure conditions: A first‐principles study - Bakri - 2011 - physica status solidi (b) - Wiley Online …Web
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@article{osti_1660986, title = {High-pressure elastic properties of dolomite melt supporting carbonate-induced melting in deep upper mantle}, author = {Xu, Man and Jing, Zhicheng and Bajgain, Suraj K. and Mookherjee, Mainak and Van Orman, James A. and Yu, Tony and Wang, Yanbin}, abstractNote = {Deeply subducted carbonates likely …Web
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We report the crystal structures of two high-pressure poly- morphs of dolomite observed above 17 GPa and 35 GPa. The occurrence of two polymorphs of dolomite in a similar …Web
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Synchrotron single crystal X-ray diffraction experiments at high-pressure and high-temperature conditions were performed up to 20 GPa and 573.0(2) K on a fully-ordered stoichiometric dolomite and ...Web
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When limestone or dolomite is subjected to high temperatures and pressures, it undergoes a chemical and mineralogical transformation. The original minerals and textures are destroyed, and …Web
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Dolomite is one of the major mineral forms in which carbon is subducted into the Earth's mantle. End-member CaMg(CO 3) 2 dolomite typically breaks down upon compression into two carbonates at 5–6 GPa in the temperature range of 800–1200 K (Shirasaka et al. 2002).However, high-pressure X-ray diffraction experiments have …Web
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In situ high-temperature Raman and Fourier transform infrared spectra were measured for aragonite, strontianite, cerussite, and witherite at ambient pressure. The orthorhombic to trigonal phase transitions were observed by the vibrational spectra for aragonite and witherite, at the temperatures of 773 and 1150 K, respectively. The …Web
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In order to understand the effect of Fe on the stability of dolomite at high pressure, several experiments have been carried out using multi-anvil apparatus at pressures up to 8 GPa and ...Web
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A high-temperature and high-pressure environment typically forms under these deep-depth conditions, which causes cracks and sutures to develop and grain dolomite to form. Some researchers believe that burial dolomitization is closely related to type of circulating pore waters ( Li et al., 2016 ).Web
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The high-pressure phase could not be characterized. DFT calculations were used to explore the relative stability of several potential high-pressure phases (dolomite-II-, dolomite-III- and dolomite-V-type structures), and suggest that the dolomite-V phase is the thermodynamically stable phase above 5 GPa.Web
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It has been pointed out that double carbonates, and in particular dolomite, could transform to a significantly denser phase at high pressure with a volume comparable, and therefore thermodynamically competitive, to the assemblage of aragonite + magnesite.In such a case, thermodynamic considerations would imply that the high …Web
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Consequently, we typically find high pressure-temperature (P-T) metamorphic rocks in the centers of mountain ranges, with lower P-T rocks near the range margins. ... Figure 9.26, for example, is a photo of a skarn formed by metamorphism of a siliceous dolomite. The rock contains recrystallized blue calcite, red-grown garnet, and green pyroxene.Web
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All of the previous high pressure experiments indicated that dolomite should decompose at pressures over 5 GPa between 600 °C and 1200 °C. However, this …Web
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The spin transition of iron can greatly affect the stability and various physical properties of iron-bearing carbonates at high pressure. Here, we reported laser Raman measurements on iron-bearing dolomite and siderite at high pressure and room temperature. Raman modes of siderite FeCO3 were investigated up to 75 GPa in the …Web
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Application of the calcite and dolomite Raman pressure sensors should be made on condition that no phase transitions or breakdown reactions occur under high P‐T conditions, with errors of ±50 ...Web
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Energy-dispersive X-ray powder diffraction spectra have been collected for aragonite (CaCO3) and dolomite [CaMg(CO3)2] at high pressure and high temperature, using synchrotron radiation and a ...Web
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For dolomite melts, viscosities were measured at pressures >2.9 GPa to avoid partial melting <~3 GPa (ref. 36 ). For both carbonate melts, ultralow viscosity values were obtained: 0.006–0.007 Pa ...Web
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The structure of the high pressure polymorph "dolomite-IIIc" was solved, which crystallizes in the space group P1¯ with Z = 8 formula units. The combined experimental and theoretical findings ...Web
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It has been suggested that high-pressure dolomite (dolomite-III) 69 and magnesite are the major carbonate phase that is stable in the Earth's lower mantle 69,70,71,72,73.Web
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These transformations are due to the high temperature and low pressure which characterize the firing process and are dependent on the chemical and mineralogical compositions of the original clay, ... Dolomite is used as an additive to ceramic masses due to the high content of CaO and MgO, which are fluxes. As a consequence, the addition of ...Web
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Synchrotron single-crystal X-ray diffraction experiments at high-pressure and high-temperature conditions were performed up to 20 GPa and 573.0(2) K on a fully ordered stoichiometric dolomite and a partially disordered stoichiometric dolomite [order parameter, s = 0.26(6)]. The ordered dolomite was found to be stable up to approximately 14 GPa …Web
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Energy-dispersive X-ray powder diffraction spectra have been collected for aragonite (CaCOr) and dolomite [CaMg(COr)r] at high pressure and high temperature, using synchrotron radiation and a cubic multi-anvil apparatus. Unit-cell volumes were measured up to 7 GPa and 1073 K along several isothermal paths. This study has confirmed …Web
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Structural parameters have been refined using X-ray intensity data for a stoichiometric dolomite single crystal at room pressure and at 1.50, 2.90,3.70, and 4.69 GPa; and for a single crystal of a ferroan dolomite with approximately 70 molo/o CaFe(COr)' at room pressure and at 1.90,2.97, and 4.0 GPa. The principal structural change with …Web
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High-pressure polymorphs of dolomite are possibly the main carbon carrier in the subduction zone because high-pressure enhances the thermodynamic stability …Web
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Elevated-temp. and elevated-pressure expts. demonstrate that dolomite nucleation and growth always are preceded by very high-magnesium calcite formation. It remains to be demonstrated whether microbial-mediated growth of very high-magnesium calcite in nature provides a precursor to dolomite nucleation and growth analogous to …Web
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The paper studies the uniaxial compression mechanical properties of pillars under the deep and high-humidity environment. We make the pillars cored from the −750 m mine room of Wengfu Phosphate Mine into the standard dolomite samples and test with a humidity control device developed by ourselves. Combining with uniaxial compression …Web
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High-pressure elastic properties of dolomite melt supporting carbonate-induced melting in deep upper mantle Materials and Methods. Starting Materials. The …Web
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Dolomite breakdown is due to pressure increase, and the reaction has been bracketed in [23] for CaMg(CO 3) 2 end-member (reaction (7) in Fig. 4). In the present study, the dolomite breakdown reaction is shifted toward higher P and lower T, which is likely an effect of iron addition to the carbonate. 4.2.Web
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