Volcán Atitlán

Volcán Atitlán is one of several conical stratovolcanoes in the Guatemalan highlands. Along with Tolimán to the north, it forms a dramatic backdrop to Lake Atitlán. The summit directly overlies the inferred margin of the Pleistocene Atitlán III caldera and is the highest of three large post-caldera stratovolcanoes constructed near the southern caldera rim. The volcano consequently post-dates the eruption of the voluminous, roughly 85,000-year-old rhyolitic Los Chocoyos tephra associated with formation of the Atitlán III caldera. The andesitic Volcán Atitlán is younger than Tolimán 3 km away on the N flank, although their earlier activity overlapped. In contrast to Tolimán, Atitlán displays a thick pyroclastic cover. The northern side of the volcano is wooded to near the summit, whereas the upper 1,000 m of the southern slopes are unvegetated. Predominantly explosive eruptions have been recorded since the 15th century.