Инд. авторы:	Goryainov S.V., Tse J.S., Desgreniers S., Kawaguchi S.I., Pan Y.M., Likhacheva A.Yu, Molokeev M.S.
Заглавие:	In situ X-ray diffraction study of chrysotile at high P-T conditions: transformation to the 3.65 angstrom phase
Библ. ссылка:	Goryainov S.V., Tse J.S., Desgreniers S., Kawaguchi S.I., Pan Y.M., Likhacheva A.Yu, Molokeev M.S. In situ X-ray diffraction study of chrysotile at high P-T conditions: transformation to the 3.65 angstrom phase // Physics and Chemistry of Minerals. - 2021. - Vol.48. - Iss. 10. - Art.36. - ISSN 0342-1791. - EISSN 1432-2021.
Внешние системы:	DOI: 10.1007/s00269-021-01160-8; WoS: 000701655500001;
Реферат:	eng: The behavior of chrysotile Mg-3(Si2O5)(OH)(4) in water medium at simultaneously high pressure and high temperature was studied by in situ synchrotron X-ray diffraction using a diamond anvil cell. In contrast to previous 'dry' experiments, chrysotile in water-saturated conditions undergoes two-phase transitions and exhibits higher thermal stability. At 260 degrees C / 3.7 GPa the initial chrysotile (phase I) transforms to the 'chrysotile-like' phase II, followed by the appearance of the 'chrysotile-like' phase III at 405 degrees C / 5.25 GPa. Phase III is characterized by enlarged interlayer distances, presumably resulting from the H2O intercalation into the interlayer space. During further compression, the 'chrysotile-like' phase III is decomposed to the 10 angstrom phase Mg-3(Si4O10)(OH)(2)center dot xH(2)O, the 3.65 angstrom phase MgSi(OH)(6), phase D, forsterite, enstatite and coesite or stishovite. The 3.65 angstrom phase appears at 8.8 GPa / 500 degrees C. The series of transformations leads to a water deficiency in the system, restricting the complete transformation from the 10 angstrom phase to the 3.65 angstrom phase. These data emphasize the crucial role of excess water in the stabilization of the high-pressure hydrous phases. The present study is the first in situ observation of sequential transformations of hydrous phases: serpentine -> 10 angstrom phase -> 3.65 angstrom phase, important as a potential water transport mechanism to the deep mantle.
Ключевые слова:	SUBDUCTION; DEEP MANTLE; WATER TRANSPORT; CRYSTAL-STRUCTURE; 10-ANGSTROM PHASE; EQUATION-OF-STATE; SYSTEM MGO-SIO2-H2O MSH; HYDROUS MAGNESIUM SILICATES; HIGH-PRESSURE STABILITY; Synchrotron radiation; X-ray diffraction; High temperature; High pressure; Serpentine; Chrysotile; ANTIGORITE;
Издано:	2021
Физ. характеристика:	36