Steven Dutch, Professor Emeritus, Natural and Applied Sciences, Universityof Wisconsin - Green Bay
This locale crams more diverse geology into a few square miles than just about anyplace else on earth. You have saline Mono Lake with its tufa pinnacles, centerpiece of a water war between Los Angeles and environmentalists. There's the Sierra Nevada fault scarp and spectacular mountain glaciation. Then there are the Quaternary Mono Craters. In the map above, moraines are in green and volcanic cones in purple. The cones are rhyolitic, consisting of obsidian domes, thick tabular flows, and domes with ejecta rings.
|Left and below: Panum Crater is the northernmost and most easily accessible of the Mono Craters, with a dirt road leading to the base. Like most of the craters it consists of a rhyolite dome surrounded by a low cone of talus and ejecta.|
|Left and below: Views of Mono Lake from Panum Crater|
|Looking north along the ejecta ring. The Sierra Nevada scarp is in the distance.|
|Looking west along the ejecta ring. The Sierra Nevada scarp is in the distance.|
|Left and below: Looking southwest at the Sierra Nevada.|
|Panum crater ejecta: a mixture of pumice and pre-volcanic alluvium.|
|View of Panum Crater from the northwest.|
|North end of the Mono Craters from California 120.|
|Left: looking south along the Mono Craters.
Below: north end of the Mono Craters.
|Left and below: the Mono Craters from the west.|
|Below: obsidian dome west of US 395 at the south end of the Mono Caters.|
|There are more glass mountains around here than you can shake a stick at. This one is just west of US 395, a short distance south of the Mono Craters. It's an obsidian dome mantled with rubble.|
Below: Views of Glass Mountain
|Close up of obsidian boulder, showing glass and streaks of frothy pumice.|
Created 14 July 2003, Last Update 08 June 2020