Ubinas Summit Elevation: 5672 m Latitude:                16.355°S  Longitude:             70.903°W A small, 1.4-km-wide caldera cuts the top of Ubinas, Peru's  most active volcano, giving it a truncated appearance.  Ubinas is the northernmost of three young volcanoes  located along a regional structural lineament about 50 km  behind the main volcanic front of Perú. The growth and  destruction of Ubinas I volcano was followed by  construction of Ubinas II volcano beginning in the mid-  Pleistocene. The upper slopes of the andesitic-to-rhyolitic  Ubinas II stratovolcano are composed primarily of  andesitic and trachyandesitic lava flows and steepen to  nearly 45 degrees. The steep-walled, 150-m-deep summit caldera contains an ash cone with a 500-m-  wide funnel-shaped vent that is 200 m deep. Debris-avalanche deposits from the collapse of the SE  flank of Ubinas about 3700 years ago extend 10 km from the volcano. Widespread plinian pumice-fall  deposits from Ubinas include one of Holocene age about 1000 years ago. Holocene lava flows are  visible on the volcano's flanks, but historical activity, documented since the 16th century, has consisted  of intermittent minor-to-moderate explosive eruptions. (Global Volcanic Program)                                                                                                                                                                                                                                                                             click to enlarge  Photo: Rolf Cosar Photo: Rolf Cosar Photo: Rolf Cosar Photo: Rolf Cosar Photo; Rolf Cosar Photo: Rolf Cosar Panoramas click on panorama HOME Google earth