UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Improving grain size analysis using computer vision techniques and implications for grain growth kinetics

Ezad, I; Einsle, J; Dobson, D; Hunt, S; Thomson, A; Brodholt, J; (2021) Improving grain size analysis using computer vision techniques and implications for grain growth kinetics. American Mineralogist , 107 (2) pp. 262-273. 10.2138/am-2021-7797. Green open access

[thumbnail of AmMin_Rev_2_submissionaccepted.pdf]
Preview
Text
AmMin_Rev_2_submissionaccepted.pdf - Accepted Version

Download (1MB) | Preview

Abstract

Earth’s physical properties and mantle dynamics are strongly dependent on mantle grain size, shape, and orientation, but these characteristics are poorly constrained. Experimental studies provide an opportunity to simulate the grain growth kinetics of mantle aggregates. The experimentally determined grain sizes can be fit to the normal grain growth law (Gn – Gn0⁠) = k0t∙exp(–ΔH/RT) and then be used to determine grain size throughout the mantle and geological time. The grain growth dynamics of spinelorthopyroxene mixtures in the upper mantle are modeled here by experimentally producing small grain sizes in the range of 0.5 to 2 µm radius at pressures and temperatures equivalent to the spinel lherzolite stability field. To accurately measure the sizes of these small grains, we have developed a computer vision workflow; using a watershed transformation, which rapidly measures 68% more grains and produces a 20% improvement in the average grain size accuracy and repeatability when compared with manual methods. Using this automated approach, we have been able to identify a significant proportion of small grains, which have been overlooked when using manual methods. This additional population of grains, when fit to the normal grain growth law, highlights the influence of improved accuracy and sample size on the estimation of grain growth kinetic parameters. Our results demonstrate that automatic computer vision enables a systematic, fast, repeatable method of grain size analysis, across large data sets, improving the accuracy of experimentally determined grain growth kinetics.

Type: Article
Title: Improving grain size analysis using computer vision techniques and implications for grain growth kinetics
Open access status: An open access version is available from UCL Discovery
DOI: 10.2138/am-2021-7797
Publisher version: https://doi.org/10.2138/am-2021-7797
Language: English
Additional information: This version is the author accepted manuscript. For information on re-use, please refer to the publisher's terms and conditions.
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Earth Sciences
URI: https://discovery.ucl.ac.uk/id/eprint/10119410
Downloads since deposit
30Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item