Rocks, their histories, their types, their practical uses, their personalities. For three hours on Sunday afternoon, Oct. 14, at Portola Valley Town Center, there will be rocks -- to look at, to touch, and to learn about from local geologists.

Expected to be on hand to talk about rocks and much more are Ted Sayre, Rowland Tabor, Sheldon Breiner, Carl Wentworth, Paul Heiple, Chet Wrucke and Chet's son Bob Wrucke, not a geologist, his father said, but a vital member of the seismology team studying the San Andreas fault.

Kids of all ages will have an opportunity to ask questions, and get answers, about topics such as how to identify a particular mineral or rock; the types of rocks, crystals, geodes, fossils and glaciers; the geologic history of Portola Valley; oil exploration; plate tectonics; volcanoes; the science of measuring and predicting earthquakes, and how to stay safe when one comes along.

Bring your own fossils! The event begins at 1 p.m. at 765 Portola Road.

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