Most volcanoes erupt both effusively and explosively, with explosive behaviour being responsible for most human fatalities. Eruption style is thought to be strongly controlled by fast conduit processes, limiting our ability for prediction. Here we address a critical question in the quest to develop ...
Where both eruptive styles exist with a single eruption phase, a common eruptive trend is from explosive to effusive activity (Fig.2). A plot using the known durations of eruptive periods and occurrence of a climactic eruption (VEI ≥ 4 in this instance), within these periods (containing...
Furthermore, eruptions are thought to be highly dynamic, with simulta- neous effusive and explosive activity and with pyroclastic edifice construc- tion and collapse all occurring within eruption timescales53. This behavior introduces an inherent bias when classifying Martian deposits as explosive vs. ...
The eruption started June 42011, and the studied volcanic material corresponds to that collected in Argentine territory at different distances from the source, between 4 and 12 June 2011. The explosive-effusive volcanic process of the first days occurred with the simultaneous emplacement of lava ...
(1) those that can be directly observed during an eruption, such as plume height or eruption start time, and (2) those that must be constrained through detailed analysis or numerical relationships. The second type includes, for example, the grain-size distribution of erupted material, which is...
Seismicity is one of the most common precursors of eruptions and it often continues after an eruption ends. But what happens in between? How do the earthquakes progress during an eruption? These questions have been studied at length for effusive eruptions, but have been hampered by detection ...
. The nature of any eruption, i.e., whether it be explosive or effusive, depends upon the presence of volatiles (primarily H-C-O-S species) in the system. These volatiles may be sourced from the magma itself (as volatiles dissolved in silicate melt) or from an external source (e.g....
We also define a 'critical condition' for the full set of initial parameters under which a transition in eruption style, from effusive to explosive or the reverse, is more likely to occur. Under these conditions, small heterogeneities in the water or crystal content of the magma, or small ...
The rapid decrease in V/Vratios during the explosive phase may be caused by melt eruption and gas emission. The V/Vratios were observed to be nearly stationary since the early effusive phase, suggesting rare presence of melts and low levels of pore pressures with degassing. These observations ...
For example, recent gas monitoring (SO2/CO2 and SO2 fluxes) at Poás volcano (Costa Rica) led to models suggesting that hydrothermal sealing may have been the cause of the explosive phreatomagmatic eruption in 201726. Despite the potential importance of lava dome permeability in regulating ...