Olivine orthopyroxenite-hosted chromitite veins in the ophiolitic mantle, Havana-Matanzas, CubaShow others and affiliations
2019 (English)In: Proceedings of the 15th SGA Biennial Meeting, 27-30 August, University of Glasgow Publicity Services , 2019, p. 569-572Conference paper, Published paper (Refereed)
Abstract [en]
The Havana-Matanzas ophiolite contains an example of chromitite veins hosted in olivine orthopyroxenites within mantle peridotites. Accessory Cr-spinei in the harzburgite and in the Ol-orthopyroxenite, and chromite in the chromitite vein show a wide range of composition (Cr# 0.39-0.75). However, the chromite in the vein and the Cr-spinel in the Ol-orthopyroxenite show similar composition with Cr#>0.7 (Cr-rich), probably related to crystallization from boninitic-like mantle melts. The study of platinum-group minerals hosted in the chromite shows that Os-rich laurite is the main mineral phase, as it is typically observed in chromitites that formed from magmas of boninitic affinity. The Ol-orthopyroxenite bands are believed to represent melt channels that formed after replacement of peridotites by a Si-rich melt with boninitic affinity. This is supported by the Cr-spinel composition of the pyroxenites (Cr#>0.7) and the low Al, Ca and Cr content of orthopyroxene. The interaction between a Si-rich melt with harzburgite/dunite formed Ol-orthopyroxenite and a Cr-saturated melt, which also circulated through the pyroxenite channels and formed the chromitite veins.
Place, publisher, year, edition, pages
University of Glasgow Publicity Services , 2019. p. 569-572
National Category
Geology
Research subject
Applied Geochemistry
Identifiers
URN: urn:nbn:se:ltu:diva-86787ISI: 000503111600147OAI: oai:DiVA.org:ltu-86787DiVA, id: diva2:1586876
Conference
15th SGA Biennial Meeting, Glasgow, Scotland, August 27-30, 2019
Note
ISBN för värdpublikation: 978-0-85261-962-9;
Forskningsfinansiär: Spanish project (CGL2015-65824); German Research Foundation (DFG); Ministerio de Educacion (Spain) (RYC-2015-17596)
2021-08-232021-08-232021-08-23Bibliographically approved