Special volcanic activity report (REAV))
Antofagasta Region, October 30, 2015 at 09: 45 hl
The National Geology and Mining Service (SERNAGEOMIN) and the Volcanological Observatory of Southern Andes (OVDAS), communicates the following:
A 09: 32HL (12: 32GMT) via the webcam of the Lascar volcano, it was observed an emission of ash to a height of 2500 m, to the north-east flank of the volcano. The seismic signal that has accompanied this process in surface, has a reduced displacement of 1cm2, which is considered low to moderate.
At the time of publication of this report, emissions of particulate matter have continued their evolution is evaluated.
The eruption was preceded by any warning sign, which leads him to believe that it probably has a phreatic origin. The last major eruption of the Lascar was in 2005 .
Due to the facts above, the technical level of volcanic alert goes to YELLOW.
The SERNAGEOMIN – OVDAS continuous online monitoring and report timely changes in the activity of the volcano.
Láscar is the most active volcano of the northern Chilean Andes. The andesitic-to-dacitic stratovolcano contains six overlapping summit craters. Prominent lava flows descend its NW flanks. An older, higher stratovolcano 5 km E, Volcán Aguas Calientes, displays a well-developed summit crater and a probable Holocene lava flow near its summit (de Silva and Francis, 1991). Láscar consists of two major edifices; activity began at the eastern volcano and then shifted to the western cone. The largest eruption took place about 26,500 years ago, and following the eruption of the Tumbres scoria flow about 9000 years ago, activity shifted back to the eastern edifice, where three overlapping craters were formed. Frequent small-to-moderate explosive eruptions have been recorded since the mid-19th century, along with periodic larger eruptions that produced ashfall hundreds of kilometers away. The largest historical eruption took place in 1993, producing pyroclastic flows to 8.5 km NW of the summit and ashfall in Buenos Aires.
October 31, 2015. Láscar, Chile :
Source : Sernageomin, GVP .
Photo : aoc.nrao.edu, Darack/Alamy.