Report on Sabancaya (Peru) — 9 December-15 December 2015
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 9 December-15 December 2015
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2015. Report on Sabancaya (Peru). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 9 December-15 December 2015. Smithsonian Institution and US Geological Survey.
15.787°S, 71.857°W; summit elev. 5960 m
All times are local (unless otherwise noted)
Instituto Geofísico del Perú (IGP) Observatorio Volcanológico del Sur (OVS) reported that during 9-14 December the number of volcano-tectonic (VT) earthquakes less than 6 km from the crater sharply increased; VT earthquakes in general were focused within 8 km of the crater at depths ranging from 3 to 15 km. White fumarolic plumes were steadily emitted, while bluish gasses were more sporadically observed. Gas plumes rose 800-1,400 m above the crater’s base. The Buenos Aires VAAC reported that during 11-12 December Sabancaya's webcam recorded weak emissions with minor amounts of ash.
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.