Particle shape analysis of volcanic clast samples with the Matlab tool MORPHEO

This paper presents a modular Matlab tool, namely MORPHEO, devoted to the study of particle morphology by Fourier analysis. A benchmark made of four sample images with different features (digitized coins, a pebble chart, gears, digitized volcanic clasts) is then proposed to assess the abilities of the software. Attention is brought to the Weibull distribution introduced to enhance fine variations of particle morphology. Finally, as an example, samples pertaining to a lahar deposit located in La Lumbre ravine (Colima Volcano, Mexico) are analysed. MORPHEO and the benchmark are freely available for research purposes.

► Description of the Matlab tool MORPHEO freely available for research purposes. ► Benchmark of four sample images provided for the sake of reproducibility. ► Weibull's distributions used to observe fine variations of particle morphology. ► Analysis of a sequence of clast samples coming from a lahar deposit.