Plate tephra: Preserved bubble walls from large slug bursts during violent Strombolian eruptions

Deep sea explosive eruptions may be not so different from subaerial eruptions

“…3b-e). This interpretation agrees again with a Strombolian-like activity (Table S1) in which bubble-walls clasts are frequently observed and interpreted to result from magma squeezed among large gas bubbles 26,27 . According to the results from Fig.…”

Tephra From the 3 March 2015 Sustained Column Related to Explosive Lava Fountain Activity at Volcán Villarrica (Chile)

“…In addition, the erupted volume is very similar to that from the Kilauea Iki Crater eruption (1959), which was the highest historical lava fountain event registered in Hawaii (height up to 580 m and erupted a total non-DRE volume between 2.1 and 5.8 × 10 6 m 3 ; Stovall et al, 2011;Klawonn et al, 2014) and slightly larger than the DRE tephra volume estimated for 2012-13 Tolbachik fissure eruptions (about 4.0 × 10 5 m 3 ; Belousov et al, 2015). In contrast, the violent Strombolian activity of Llaima volcano in 2008-2009 had lower intensity/MER values (∼1.6 × 10 4 kg/s) and lava-fountain-related column did not become sustained for the whole eruption duration, even though it produced equivalent peak thermal radiance values (89.5Wm −2 sr −1 µm −1 Wm −2 sr −1 µm −1 ; Romero et al, 2013) and a similar tephra fall volume (∼1.31 × 10 6 m 3 ) and composition (basaltic andesite) (Ruth and Calder, 2014). This suggests that the 3 March eruption of Villarrica is an example of a high-intensity end member of lava fountain-related paroxysmal events.…”

“…Tephra fall from lava fountains threatens critical infrastructure and human activities around the volcano (e.g., Allard et al, 2005;Andronico et al, 2008Andronico et al, , 2014aAndronico et al, ,b, 2015Carracedo et al, 2012). A study of tephra fall deposits from lava fountains and paroxysmal phases, especially when they are exceptionally intense, is an essential tool for early assessment of conduit dynamics, hazards and impacts (e.g., Polacci et al, 2006;Gurioli et al, 2008;Andronico and Corsaro, 2011;Stovall et al, 2011;Corsaro and Miraglia, 2014;Ruth and Calder, 2014;Ruth et al, 2016) and provides critical information for better understanding of volcanic activity.…”

Viscous plugging can enhance and modulate explosivity of strombolian eruptions

“…Such a rheological impedance -which can be termed a 'plug' -is commonly inferred, and physically plausible, at active strombolian-type vents (e.g., Gurioli et al, 2014). Textural data from many strombolian-type volcanoes support the coexistence of magmas that have contrasting rheology as a result of cooling-and degassing-driven crystallisation (e.g., Taddeucci et al, 2004;Cimarelli et al, 2010;Kremers et al, 2012;Ruth and Calder, 2013). Considering Stromboli as a canonical case during its 'normal' activity, it is very common to find both bubble-rich, crystal-poor textures and bubble-poor, crystal-rich textures intermingled within a single pyroclast (e.g., Lautze and Houghton, 2005;Polacci et al, 2006Polacci et al, , 2009Colò et al, 2010;D'Oriano et al, 2010;Gurioli et al, 2014).…”