The launch of a new GVP website is scheduled for Monday, May 20, 2013.
|Subregion Name:||California (USA)|
|Volcano Type:||Cinder cones|
|Last Known Eruption:||Unknown|
|Summit Elevation:||2191 m||7,188 feet|
|A line of cinder cones along a NNW-SSE-trending fissure has produced a series of youthful-looking lava flows. The most prominent of these is Devils Rock Garden, a thick, blocky andesitic lava flow complex that extends to the south from Tumble Buttes. Bear Wallow Butte, the source of unvegetated lava flows on its eastern and western flanks, lies at the southern end of the chain. At the northern end is Eiler Butte, constructed on a topographic high, which has also produced blocky lava flows. Miller (1989) mapped Tumble Buttes as Holocene. The Devils Rock Garden lava flow erupted from Tumble Butte south is the youngest in the area. It blocked glacial outwash channels and overlies glacial gravels and thus is younger than about 15,000 years, but not necessarily Holocene (Clynne, 2007 pers. comm.).|