SERNAGEOMIN reported continuing explosive and effusive activity at Nevados de Chillán?s Nicanor Crater during 1-15 November.
Explosions generated both plumes with moderate ash content and white steam-rich plumes that rose as high as 2 km above the crater rim.
Explosions occasionally ejected incandescent material onto the N side of the crater and the N flank.
A new dome, which had emerged around 28 October at the L7 vent, was partially destroyed by explosions on 8 November, and then regrew to 80 m long and 55 m wide.
Pyroclastic flows descended the NE flank, traveling as far as 700 m on 8 and 10 November.
The L7 lava flow, between the inactive L5 and L6 flows, slowly advanced and was 930 m long; a NE branch of L7 had not advanced since 14 October, though SE and E branches formed on 9 and 14 November, respectively.
A second active flow, L8, had not lengthened past 385 m.
Sulfur dioxide emissions averaged 300 tons per day, peaking at 462 tons per day on 14 November, and were lower than rates recorded during the last half of September.
The Alert Level remained at Yellow, the second lowest level on a four-color scale.
ONEMI stated that Alert Level Yellow (the middle level on a three-color scale) remained in place for the communities of Pinto and Coihueco, noting that the public should stay at least 2 km away from the crater.
Sources: Oficina Nacional de Emergencia-Ministerio del Interior (ONEMI) ,Servicio Nacional de Geología y Minería (SERNAGEOMIN)
Asosan (Japan)