<P> 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 . 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 . </P>
<P> 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 . 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 . </P>
when was the last time mount konocti erupted
when was the last time mount konocti erupted
11,000 years ago
11,000 years ago