Global Volcanism Program | Image GVP-07857
A geologist examines an outcrop of the 84,000-year-old Los Chocoyos Ash near Patzún, about 10 km E of Lake Atitlán. Note the charred log above his head. This pyroclastic flow unit of the Los Chocoyos deposit is up to 200 m thick and is exposed over an area of about 2,000 km2. Individual flow units of the voluminous ignimbrite are sometimes more than 100 m thick. The upper part of the deposit is characteristically salmon-pink in color as a result of oxidation of the cooling flow.
Photo by Bill Rose, 1980 (Michigan Technological University).