Fig. 2: Particle sizes in sintered veneers on in-vent lava fractures that fed ash-venting during hybrid explosive-effusive eruptions.
From: In-conduit capture of sub-micron volcanic ash particles via turbophoresis and sintering
a–c SEM images of fracture-wall surface textures in sample AN1. Ropy textures are highlighted in a; evidence of neck formation highlighted in c. d Cumulative distribution (cdf) of particle diameters \(d\), compared with a lognormal function \(\left[1+{{{{{\rm{erf}}}}}}\left({{{{{\rm{ln}}}}}}\;x-\left\langle x\right\rangle /\sigma \sqrt 2\right)\right]/2\) defined by the mean \(\left\langle x\right\rangle\) and standard deviation \(\sigma\) of the logarithm of the data \(x\). Density distribution of particles shown as \(\left\langle x\right\rangle\) (vertical tick) and 2\(\sigma\) range (horizontal line). Inset shows the mass proportion (assuming spherical particles and homogeneous melt density) of particles greater than a given diameter. e, g Microtextures observed in sample AN2. h As (d), for sample AN2. i–k Microtextures in sample CCTVAIP. Near-spherical particle is highlighted in (j). In (k), arrows indicate both angular fragment and well-sintered particle adhered to larger clast. l As d, for sample CCTVAIP. m–o Microtextures in sample CCVP. Discrete angular fragment highlighted in m. Remnants of sintering highlighted in o. p As (d), for sample CCVP.
