Fig. 4: The key dynamic processes that lead to the pyroclast textures observed.
From: Melt stripping and agglutination of pyroclasts during the explosive eruption of low viscosity magmas
The colour scheme is the same as previous figures where, green represents olivine crystals, red represents the homogenous melt and orange represents the complex melt. Gas is shown in white, and the grey at the fountain/jet edge indicates the cooler portion of the fountain/jet that is below the glass transition temperature, Tg. a Within conduit/dyke mechanical abrasion of olivine crystal cargo. b A simple depiction of the primary magma disruption and formation of melt-coated crystals and melt droplets at the free surface. We note that these primary fragmentation processes are likely to be highly variable and complex. c Stripping of the mobile, high-temperature melt from crystal surfaces (see Fig. 5a) and d in the lower velocity part of the fountain, in-flight particle agglutination (see Fig. 5b). Note that agglutination processes shown in d can also occur in the subsurface when velocities are reduced due to conduit widening, for example.
