August-September 2003 small vulcanian eruption at the Nevados de Chillán Volcanic Complex (36°50'S), Southern Andes (Chile)

during the winter months of august-september 2003 a small (vei=0-1) eruption took place at the 9 km long fissure-like nevados de chillán volcanic complex (36°50's), that includes nuevo (formed between 1906 and 1945) and arrau (formed in the 1973-1986 period) volcanoes. only the local inhabitants and tourists of the ski resort located at the foothills noted the eruption. from august 29 to september 4, 2003, low-magnitude explosive events occurred and brown-greyish to white gas and ash columns reached up to 400 to 500 m above the crater, rising at periods that lasted for 20 to 25 minutes. after the first week, explosions became more sporadic and occurred at two-three day intervals. strong prevailing winds from the north dispersed the low-altitude plume to the sse until the eruption finally stopped by the middle of september. a new compound crater is now present in the saddle between nuevo and arrau volcanoes. this 64 m fissure-like double crater is surrounded by an area of intense fumaroles near to nuevo volcano suggesting the renewal of activity in the complex