Global Volcanism Program | Image GVP-07276
Light-colored rhyolitic airfall pumice deposits from Coatepeque caldera are exposed in a quarry 20 km east of the caldera. These pumice-fall deposits blanket much of SW El Salvador, and along with associated pyroclastic-flow deposits have a volume of about 56 cu km. The earlier biotite-bearing Arce deposits originated during the largest eruption from Coatepeque about 72,000 years ago and are a half-meter thick at the Guatemalan border. The overlying Congo deposits originated during the second largest eruption of Coatepeque.
Photo by Carlos Pullinger, 1996 (Servicio Nacional de Estudios Territoriales, El Salvador).