Logo link to homepage

Report on Ubinas (Peru) — 4 June-10 June 2014


Ubinas

Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 4 June-10 June 2014
Managing Editor: Sally Sennert.

Please cite this report as:

Global Volcanism Program, 2014. Report on Ubinas (Peru) (Sennert, S, ed.). Weekly Volcanic Activity Report, 4 June-10 June 2014. Smithsonian Institution and US Geological Survey.

Weekly Report (4 June-10 June 2014)

Ubinas

Peru

16.345°S, 70.8972°W; summit elev. 5608 m

All times are local (unless otherwise noted)


In a press release from 5 June, IGP's Observatorio Volcanologico de Arequipa (IGP-OVA) and Observatorio Vulcanológico del INGEMMET (OVI) reported that an Alert Level Orange continued for residents affected by the Ubinas eruption. Residents of Querapi and Tonohaya remained evacuated. The report noted that a significant and continuous release of ash emissions and gasses were observed during the previous days. Gas-and-ash plumes observed during 5-7 June rose 0.2-2 km above the crater. Minor ashfall was reported in Lloque and Yungas during 6-7 June.

Geological Summary. The truncated appearance of Ubinas, Perú's most active volcano, is a result of a 1.4-km-wide crater at the summit. It is the northernmost of three young volcanoes located along a regional structural lineament about 50 km behind the main volcanic front. The growth and destruction of Ubinas I was followed by construction of Ubinas II beginning in the mid-Pleistocene. The upper slopes of the andesitic-to-rhyolitic Ubinas II stratovolcano are composed primarily of andesitic and trachyandesitic lava flows and steepen to nearly 45°. The steep-walled, 150-m-deep summit crater contains an ash cone with a 500-m-wide funnel-shaped vent that is 200 m deep. Debris-avalanche deposits from the collapse of the SE flank about 3,700 years ago extend 10 km from the volcano. Widespread Plinian pumice-fall deposits include one from about 1,000 years ago. Holocene lava flows are visible on the flanks, but activity documented since the 16th century has consisted of intermittent minor-to-moderate explosive eruptions.

Sources: Instituto Geofísico del Perú (IGP), Instituto Geológico Minero y Metalúrgico (INGEMMET)