Geology of Mount Diablo
[Return to the Natural History of Mt. Diablo]


Wind cave
Photograph by Roi Peers

Erosion "wind caves" are common features in the "Domengine" sandstone near Rock City.


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.


"It is clear that geology is not a static field - our interpretations of the landscape are continually changing
as we learn more when we look at the landscape with new ideas."     - -  
Doris Sloan, UC Berkeley


FEATURED ARTICLES

Overview of the Geology of Mt. Diablo State Park
Geologic Map of Mt. Diablo
Guide to the Geology of Mount Diablo State Park
Rock Descriptions and Ages
Geology Road Log for Mt. Diablo
Mt. Diablo "Trail Through Time" Project
Frequently Asked Questions About the Geology of Mt. Diablo
Mt. Diablo's Mining - A short summary
Collection of Articles on Mount Diablo Mining - early writings on mining activities during the late 1800's compiled by Chris Valle-Riestra.
Clayton Diabase Quarry (Reprint from Mount Diablo Review - Spring 2004)
Quicksilver Deposits of the Mt. Diablo District - USGS Bulletin 922-B
Rugged Plants Struggle to Survive on Barren Serpentine Soil - from NCGS Newsletter
Fossil Quarry Reveals Bygone Secrets - Article from the Contra Costa Times by John Boudreau
Pliocene Park - what our area was like several million years ago - Reprinted from Mount Diablo Review
A Suggested Reading List on the Geology of Mt. Diablo
Geoscience Links
Also see: Publications On-line for additional articles.

Some of the pages on the Geology of Mount Diablo are presently under construction. Future pages will be activated as they become available. We would like to hear from you on suggestions and comments for the presentation of the geology of Mt. Diablo. Please contact Roi Peers.

Astronomy Geology Plants Wildlife

MDIA Store | Outdoor Activities | Schedule of Events | State Park Information | MDIA Publications
Home | Search | About MDIA | Summit Museum | Natural History | Cultural History | Location Map

MOUNT DIABLO INTERPRETIVE ASSOCIATION
P.O. Box 346 - Walnut Creek, CA 94597-0346
(925) 927-7222 / FAX: (877) 349-5016