Abstract
Phase relations in the system MgSiO 3-FeSiO 3 were studied experimentally up to a pressure of 24 GPa at 1800°C. Alumina-free tetragonal garnet exists in the pressure range from 16 to 23.5 GPa. The compositional range of the tetragonal garnet phase extends from pure MgSiO 3 to (Mg 0.76Fe 0.24)SiO 3 at 18.2 GPa and 1800°C. The sequence of the phase transitions in Mg-rich part of this system at 1800°C is: clinopyroxene→17GPatetragonal garnet→22.5GPailmenite→23GPaMg-perovskite. The lattice constants of tetragonal garnet increase with increasing iron content from a= 11.517 ± 0.002Åandc = 11.435 ± 0.003Åfor MgSiO 3toa = 11.543 ± 0.002Å and c = 11.476 ± 0.003Å for (Mg 0.76Fe 0.24)SiO 3. Cubic garnet was not observed in the pressure and temperature range studied in this work. The alumina-free tetragonal garnet observed in this study may exist in the harzbergite layer in the descending slab.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
