Medicine Lake Volcano Medicine Lake Volcano Medicine Lake Volcano is a large shield volcano in northeastern California about northeast of Mount Shasta. The volcano is located in a zone of east-west crustal extension east of the main axis of the Cascade Volcanic Arc and the Cascade Range. The thick shield is from east to west and from north to south, and covers more than . The underlying rock has downwarped by under the center of the volcano. The volcano is primarily composed of basalt and basaltic andesite lava flows, and has a caldera at the center. The Medicine Lake shield rises about above
Chiles (volcano) Chiles (volcano) Chiles is a volcano on the border of Colombia and Ecuador. It lies south-east of the volcano Cerro Negro de Mayasquer, and the two peaks are considered part of the same Chiles-Cerro Negro volcanic complex. The volcanoes, together with the Cumbal are andesitic in rock type. A 1936 eruption reported by the Colombian government agency Ingeominas may have been from the Ecuadorean volcano Reventador, otherwise the volcano has not erupted for around 160,000 years. On 20 October 2014, the Servicio Geológico Colombiano (SGC) reported that a M 5.8 earthquake, the largest to date, occurred in the vicinity of