The lake was formed by the
1872 Lone Pine earthquake on Tuesday, March 26 of that year when of the Owens Valley dropped approximately 20 feet (6 m) (see
graben) and a new spring opened, causing water to fill the lowland. The lake was named for the Diaz family who established a ranch here when brothers Rafael and Eleuterio Diaz emigrated from
Chile in the 1860s. They owned and operated a successful
cattle ranch until the land was sold to the city of
Los Angeles. ==Access==