Eclogite xenoliths from the Jericho and Muskox kimberlites, Nunavut, Canada ...

• Main Author: Beausoleil, Yvette Léa
• Format: Text
• Language: English
• Published: University of British Columbia 2012
• Subjects: Nunavut; Canada; muskox
• Online Access: https://dx.doi.org/10.14288/1.0053564; https://doi.library.ubc.ca/10.14288/1.0053564

A total of 109 eclogite xenoliths from the Jericho and Muskox kimberlites (Nunavut, Canada) were studied petrographically and mineralogically to constrain their depth distribution within the Northern Slave mantle. The eclogites are dominated by pyrope-almandine and omphacite with accessory rutile, apatite and olivine. Garnet-clinopyroxene thermobaromtry suggests that Northern Slave eclogites formed at 670 -1300 °C and 25 – 70 kbar. Eclogites were classified into Group A, B, or C based on mineral composition and into massive and foliated textural types. Group A Northern Slave eclogites may have formed as cumulates from mantle mafic melts, whereas Group B and C eclogites are interpreted as modified subducted oceanic crust. All Northern Slave eclogites were subjected to partial melting and recrystallization, which produced secondary high-MgO garnet and clinopyroxene, phlogopite, amphibole carbonates and spinel group minerals. The recrystallization was caused by an influx of carbonatitic and hydrous hot fluid. ...