Correction (posted Feb. 27, 2012): The correct address for the Tri-Valley Group event is 1188 S. Livermore Ave.
The Sierra Club Tri-Valley Group is co-sponsoring, along with the Livermore Heritage Guild, a talk by Ken Lavin on the geology of Mount Diablo.
The event will be at the Livermore Public Library, 1188 S. Livermore Ave., in Livermore, on Wednesday, March 21 at 7 pm. Refreshments will be served. A $10 donation is suggested.