when was the last time mount konocti erupted
Mount Konocti Mount Konocti probably first erupted some 350,000 years ago and last erupted 11,000 years ago. Mount Konocti has an explosive, eruptive history with devastating lava flows ending about 13,000 years ago that formed the mountains from Clearlake Oaks to Ukiah, all of which now are covered by trees so the ancient flows are really hard to find.[4] Clear Lake is much older and is possibly the oldest securely dated lake in North America. Core samples taken by U.S. Geological Survey geologists in 1973 and 1980 have been dated to 480,000 years.[citation needed]
Mount Etna Volcanic activity first took place at Etna about 500,000 years ago, with eruptions occurring beneath the sea off the ancient coastline of Sicily.[15] About 300,000 years ago, volcanism began occurring to the southwest of the summit (centre top of volcano) then, before activity moved towards the present centre 170,000 years ago. Eruptions at this time built up the first major volcanic edifice, forming a stratovolcano in alternating explosive and effusive eruptions. The growth of the mountain was occasionally interrupted by major eruptions, leading to the collapse of the summit to form calderas.