Mt. Diablo Photos










Mt. Diablo Rock Quarry







Geology: Our understanding of the geological history of the
rocks and structure of Mt. Diablo has undergone major changes during the past 30
years, and even now geologists are still trying to unravel the complicated
history of the mountain. This complex history is not unique to the mountain, but
to our region as a whole, since Mt. Diablo has been caught up in the processes
that have shaped the Coast Ranges over the last several million years.
Paleontology: Mount Diablo State Park contains geological formations rich in
fossil resources. Marine mollusks of Miocene age are abundant along the southern
flank of the mountain. Fossil plant material is also common in this area. Along
the southern boundary, 9 million year old river deposits have yielded a large
number of vertebrate fossil fragments including sabre-tooth cats, mastodons,
horses, camels, and llamas.
At 3800 feet, Mt. Diablo is a standout feature of the local landscape. What few
people realize, however, is that the rocks exposed in Mt. Diablo State Park
preserve evidence of paleoenvironments spanning more than 100 million years.
Some sediments record the presence of ancient seas; others indicate marshy
grasslands that supported a very different flora and fauna from that in the park
today.
Working to create public access to this resource, the University of California
Museum of Paleontology is collaborating with Mt. Diablo State Park and the Mt.
Diablo Interpretive Association, and other local groups to make a "Trail Through
Time". By linking some existing trails with new segments (see map), the
consortium will create an 8-mile hiking path that winds past rock outcrops,
fossil sites, Bay Area vistas, and areas of botanical and archeological
interest. Visitors will be able to view vertebrate, invertebrate, and plant
fossils on their hike, and will read about California's geologic history at
marked information stations.
Although parts of the Trail Through Time involve a vigorous hike, it will still
be accessible to the disabled