Easy Chair Crater is a large maar, part of the Lunar Crater Volcanic Field east of Tonopah, Nevada.  Over 200 volcanic vents have been identified within the region w/ the last eruption occurring roughly 10,000-38,000 years ago.  At this site, a short trail leads one to the crater rim, Easy Chair's eruption dating to 140,000 ± 5000 years.  Large green olivene crystals can be found in abundance.