Global Volcanism Program | Image GVP-05958
Uplift at Alid has exposed thick sequences of reddish, well-stratified siltstone beds, some very fossiliferous, which accumulated in a tidal or inter-tidal environment. High in the sequence there are some pillow basalts. At the very top of the sequence on the left is a few-meters-thick cover of light-colored rhyolitic Plinian pumice fallout.
Photo by Wendell Duffield, 1996 (U.S. Geological Survey).