The textures, formation and dynamics of rare high-MgO komatiite pillow lavas

Staude, S. and Jones, T.J. and Markl, G. (2020) The textures, formation and dynamics of rare high-MgO komatiite pillow lavas. Precambrian Research, 343. ISSN 0301-9268

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Abstract

Pillow lavas are an abundant morphological lava type both on Earth and on some extraterrestrial bodies. We examine pillows from Kambalda (Western Australia) komatiites, that uniquely preserve pillow necks, inter-pillow cavities, and internal crusts. Our study is the first description of true pillows from an Archaean high-MgO (~31%) komatiite. Their size ranges from 0.5 to 5 cm and most have equal vertical and horizontal axes. Due to very low melt viscosities (~0.01 – 0.1 Pa s), these komatiite pillows are one to two orders of magnitude smaller than modern basaltic counterparts. True high-MgO komatiites, such as those at Kambalda, require a low flow rate, potentially found on distal flow edges. Such low flow rates are in conflict with the high flow velocities generally assumed for komatiites, and hence explains the rarity of komatiite pillow lavas.

Item Type:
Journal Article
Journal or Publication Title:
Precambrian Research
Additional Information:
This is the author’s version of a work that was accepted for publication in Precambrian Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Precambrian Research, 343, 105729, 20220 DOI: 10.1016/j.precamres.2020.105729
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/1900/1906
Subjects:
ID Code:
176263
Deposited By:
Deposited On:
06 Oct 2022 14:20
Refereed?:
Yes
Published?:
Published
Last Modified:
22 Nov 2022 11:50