Nicoli, Gautier and Holness, Marian B. and Neufeld, Jerome A. and Farr, Robert (2018) Microstructural evidence for crystallization regimes in mafic intrusions: a case study from the Little Minch Sill Complex, Scotland. Contributions to Mineralogy and Petrology, 173 (12). ISSN 0010-7999 DOI https://doi.org/10.1007/s00410-018-1525-7
![]() |
Text
Nicoli_et_al-2018-Contributions_to_Mineralogy_and_Petrology.pdf - Published Version Download (2MB) |
Abstract
The magma forming the 20 m thick crinanitic/picrodoleritic Dun Raisburgh sill, part of the Little Minch Sill Complex of NW Scotland, comprised a mafic carrier liquid with a crystal cargo of plagioclase and olivine (1 vol%). The olivine component of the cargo settled on the floor of the intrusion while the more buoyant plagioclase component remained suspended during solidification, resulting in a relatively high plagioclase content in the centre of the sill. The settled olivine grains form a lower fining-upwards sequence overlain by a poorly sorted accumulation formed of grains that grew within the convecting magma. The accumulation of olivine on the sill floor occurred over 5–10 weeks, synchronous with the upwards-propagation of a solidification front comprising a porous (~ 70 vol% interstitial liquid) plagioclase-rich crystal mush.
Item Type: | Article |
---|---|
Uncontrolled Keywords: | 2018AREP; IA73 |
Subjects: | 05 - Petrology - Igneous, Metamorphic and Volcanic Studies |
Divisions: | 05 - Petrology - Igneous, Metamorphic and Volcanic Studies |
Journal or Publication Title: | Contributions to Mineralogy and Petrology |
Volume: | 173 |
Identification Number: | https://doi.org/10.1007/s00410-018-1525-7 |
Depositing User: | Sarah Humbert |
Date Deposited: | 23 Nov 2018 12:01 |
Last Modified: | 23 Nov 2018 12:01 |
URI: | http://eprints.esc.cam.ac.uk/id/eprint/4361 |
Actions (login required)
![]() |
View Item |