Report on Sabancaya (Peru) — 28 March-3 April 2018
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
28 March-3 April 2018
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2018. Report on Sabancaya (Peru). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 28 March-3 April 2018. 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 explosive activity at Sabancaya was similar compared to the previous week; explosions averaged 18 per day during 26 March-1 April. Seismicity was dominated by long-period events, with signals indicating emissions. Gas-and-ash plumes rose as high as 4.7 km above the crater rim and drifted 50 km SW and NW. The sulfur dioxide flux was high, at 2,855 tons per day on 30 March. The MIROVA system detected six thermal anomalies. On 28 March a lahar which began at 1113 descended the SE flank towards the Sallalli river. The report noted that the public should not to approach the crater within a 12-km radius.
Geological Summary. 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.
Sources: Instituto Geológico Minero y Metalúrgico (INGEMMET), Instituto Geofísico del Perú (IGP)