Join this rocking hike. Find out about the geological activity of the Puente Hills at this 4 mile moderate hike into the lovely Dark Canyon. Lead by one of our trail watch volunteer who is also a geologist. He will present local geology, the geologic history and the formation of oil, and overall Los Angeles geology.  The hike, about 4,500 ft long, will also serve as our guide for a description of the history of the earth (4,500 million years). Along the way, we will discuss plate tectonics, groundwater, evolution and local faults.   No dogs.