The Lunar Lake caldera is in northern Nye County, Nev., about 70 mi (110 km) east-northeast of Tonopah. It is the youngest caldera in the central Nevada multiple-caldron complex and the source of the tuff of Lunar Cuesta, a multiple-flow simple cooling unit of quarts latitic welded tuff that is about 25 m.y. old. The tuff was distributed over an area of nearly 3,000 mi2 (7,770 km2 ) and has a volume of approximately 90 mi3 (375 km3 ). The Lunar Lake caldera is the site of the Lunar Crater basalt field which contains basalts of Pleistocene and probably Holocene age. These basalts were fed from northeast-trending fissures that had much earlier served as vents for ash-flow tuffs and lavas, possibly including the tuff of Lunar Cuesta.