Mineral inclusions in rutile: A novel recorder of HP-UHP metamorphism

摘要: The ability to accurately constrain the secular record of high- and ultra-high pressure metamorphism on Earth is potentially hampered as these rocks are metastable prone retrogression, particularly during exhumation. Rutile among most widespread best preserved minerals in a hitherto untested approach use mineral inclusions within rutile such conditions. In this study, rutiles from three different ultrahigh-pressure massifs have been investigated for inclusions. shown contain high-pressure omphacite, garnet high silica phengite, well diagnostic minerals, including first reported occurrence exceptionally monomineralic coesite Dora–Maira massif. Chemical comparison inclusion matrix phases show that generally represent peak metamorphic assemblages; although rare prograde titanite, omphacite corundum also identified implying grows continuously burial traps mineralogic evidence evolution. Pressure estimates obtained inclusions, when used conjunction with Zr-in-rutile thermometry, can provide additional constraints conditions host rock. This study demonstrates an excellent repository may profoundly change way we investigate recover events both detrital populations partially retrogressed samples.