Report on Sabancaya (Peru) — 5 April-11 April 2017
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 5 April-11 April 2017
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2017. Report on Sabancaya (Peru). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 5 April-11 April 2017. Smithsonian Institution and US Geological Survey.
15.787°S, 71.857°W; summit elev. 5960 m
All times are local (unless otherwise noted)
Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that during 3-9 April seismicity at Sabancaya declined compared to the previous week, with an average of 27 explosions recorded per day. Ash plumes rose as high as 3.2 km above the crater rim (on 8 April) and drifted more than 40 km NW and NE. Ashfall was reported in Pinchollo (20 km N), Maca, and Chivay. The Buenos Aires VAAC reported that diffuse ash plumes drifted 100 km E on 9 April. Intermittent ash emissions during 10-11 April rose as high as 7 km (23,000 ft) a.s.l. and drifted SE. The Alert Level remained at Orange (the second highest level on a four-color scale).
Geologic Background. Sabancaya, located in the saddle NE of Ampato and SE of Hualca Hualca volcanoes, is the youngest of these volcanic centers and the only one to have erupted in historical time. The oldest of the three, Nevado Hualca Hualca, is of probable late-Pliocene to early Pleistocene age. The name Sabancaya (meaning "tongue of fire" in the Quechua language) first appeared in records in 1595 CE, suggesting activity prior to that date. Holocene activity has consisted of Plinian eruptions followed by emission of voluminous andesitic and dacitic lava flows, which form an extensive apron around the volcano on all sides but the south. Records of historical eruptions date back to 1750.