Sometimes you just need to take a break. I am a bit shocked to realise that this one has been more than a month, but the mood has been strange waiting for something to happen on the mountain. And last night it did. Just a hiccup, but a significant one; what is called a phreatic eruption. To get this show back on the road, some borrowed material. First, the USGS definition of a phreatic eruption:
Phreatic eruptions are steam-driven explosions that occur when water beneath the ground or on the surface is heated by magma, lava, hot rocks, or new volcanic deposits. The intense heat of such material may cause water to boil and flash to steam, thereby generating an explosion of steam, water, ash, blocks, and bombs.
Jackie Pomeroy, who has been posting daily updates on the Facebook group Community Ubud, writes this morning:
A note late last night from the team at the observation post, stated (Google + my edits) :The enlarged fracture was observed from the satellite about 15 November. The Aster TIR satellite also captured the thermal energy increase on November 15, 2015. This morning (Tuesday) at about 8 am we flew the drones and the gas measurements on the plume this morning showed high levels of CO2 (carbon dioxide) and H2O (water). SO2 (sulfur dioxide) is low, possibly due to scrubbing factor, SO2 is trapped in hydrothermal water in the body of Mount Agung. But the high CO2 indicates that the observed white smoke has had a contribution of magma, this smoke is 100% volcanic origin. We’ve had discussions with the world’s geochemists, they agreed that the smoke for this although dominated by water vapor but has a magmatic component that is substantial.
The seismic numbers remain small, but overnight they include a mix of “blowing” quakes from the gas, harmonic and non-harmonic tremors.
Normal original posts will resume shortly. This image of Agung was taken a week ago from a restaurant that had just reopened after two months of waiting. I don’t imagine that it is open today. The economic cost to Bali of this uncertainty is difficult to quantify.