We are currently having technical problems with the volcano profiles, Weekly Reports, and Current Eruptions pages, but expect to have them restored on 24 May. Sorry for the inconvenience.
Logo link to homepage

Report on Ubinas (Peru) — 30 December-5 January 2021


Ubinas

Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 30 December-5 January 2021
Managing Editor: Sally Sennert.

Please cite this report as:

Global Volcanism Program, 2020. Report on Ubinas (Peru) (Sennert, S, ed.). Weekly Volcanic Activity Report, 30 December-5 January 2021. Smithsonian Institution and US Geological Survey.

Weekly Report (30 December-5 January 2021)

Ubinas

Peru

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

All times are local (unless otherwise noted)


Instituto Geofísico del Perú (IGP) reported that at 1659 on 31 December and at 1746 on 1 January low-volume lahars descended the Volcánmayo drainage on Ubinas’s SE flank and damaged parts of the highway linking Arequipa, Querapi, Ubinas, and Huarina. The Alert Level remained at Yellow (the second lowest level on a four-color scale).

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.

Source: Instituto Geofísico del Perú (IGP)