Kimberlites from the Wawa area, Ontario

Felix V. Kaminsky*, Sergei M. Sablukov, Ludmila I. Sablukova, Vladimir S. Shchukin, Dante Canil

*Corresponding author for this work

Research output: Contribution to journalReview articlepeer-review

28 Citations (Scopus)

Abstract

Two newly discovered kimberlites from the Wawa area, Ontario, are Group-1 kimberlites in their petrographic, mineralogical, geochemical, and isotopic features. They contain mantle minerals and xenoliths of the Fe-Ti-association (magnesian ilmenite, iron-rich olivine, orange Ti-pyrope garnet, augite, and ferroan enstatite) and of the Cr-association (chromian spinel, forsteritic olivine, purple Cr-pyrope garnets, chromian diopside, and enstatite); minerals of Fe-Ti-association are much more abundant. Minerals of eclogitic association are absent. Both G-10 pyrope garnets and high Cr spinels typically associated with diamond are represented in the Cr-association. The average age of the kimberlites is 1097 ± 7 Ma; i.e., contemporaneous with other alkaline igneous rocks in the Wawa area. Equilibration pressures and temperatures of mantle xenoliths plot close to a 40-45 mW m-2 geotherm. On the basis of the Ni-in-garnet geothermometer, garnets from the Wawa kimberlites equilibrated at 800-1350°C, and at least in part within the diamond stability field. It is likely that kimberlitic magma was derived from light rare earth-element-enriched asthenospheric mantle.

Original languageEnglish
Pages (from-to)1819-1838
Number of pages20
JournalCanadian Journal of Earth Sciences
Volume39
Issue number12
DOIs
Publication statusPublished - Dec 2002
Externally publishedYes

Fingerprint

Dive into the research topics of 'Kimberlites from the Wawa area, Ontario'. Together they form a unique fingerprint.

Cite this