Kirsten Anderberg's URBAN ADVENTURES: Chatsworth Park, San Fernando Valley

Chatsworth Park (Photo: K. Anderberg, 2009)

Chatsworth Park is a unique park located in the northwestern flank of the San Fernando Valley, in Los Angeles County, CA. The hills and sandstone rocks behind the park are part of the Simi Hills, and are unique geologically. These hills were a favored route of stage coaches and wagon trains in the mid-late 1800's and wagon wheel ruts still remain up in the hills behind the park. When I was a kid in the 1960's, we used to picnic at the park, and it was fun as you could walk as far back as you wanted into the rocks. As kids, we used to love walking into the train tunnels up on the hill in the park. Nowadays, there are fences all around the bottom of the park so you cannot climb on the rocks where I used to as a kid. And the train tunnels are completely off limits now. In my teens, in the 1970's, we used to go to the park and climb up on the rocks at night and drink beer. The park is nowadays locked, with a gate, at night. Yet there are supposedly campsites and hiking trails up the hills from Chatsworth Park, so I still have some investingating to do. The park was something I took for granted as a kid, but now as an adult, I can see how unique the rocks and rock formations at the park are and it makes me want to research to learn more about this park. That is what this page is all about...my own curiosity about a park that I grew up with in my backyard.

The rocks in Chatsworth Park were deposited during the Age of Dinosaurs, and are "composed of a single and very thick geologic unit called the "Chico Formation," which is of the Upper Cretaceaous age. The thickness is estimated to be 6,000 feet and the age approximately 80 million years old." All rock layers in the Simi Hills lean toward the northwest at angles of 10 - 30 degrees and they have all been uplifted to higher elevations due to seismic activity. There is a fault running through the rocks and it separates the older Chico formation from the newer 20 million year old Miocene Formation, which created the rolling hills on the valley floor in that area. "Vertical movement along the fault may be as much as 5,000 feet." Rain and wind, especially the powerful Santa Ana winds, have sculpted holes in the rocks that birds use for nesting. During the Upper Cretaceous Period, the Simi Hills and San Fernando Valley were under the ocean. "Formation of these sandstone layers have been interpreted to be the result of deposition of successive avalanches on the ocean floor." (the information for this paragraph came from "Santa Susana Over the Pass...Into the Past," see bibliography at bottom of page).

Chatsworth Park Warnings (Photo: K. Anderberg, 2009)

Chatsworth Park (Photo: K. Anderberg, 2009)

The following resource was referenced in the creation of this page:
Sculptured Hills - A Look at the Geology of the Simi Hills, L.J. Herrera, CA Registered Geologist, 1973, from the booklet, Santa Susana Over the Pass - Into the Past, by Santa Susana Mountain Park Association (from the E.P. Foster Library, Ventura, CA collection)

Some other Chatsworth Park Resources:
Santa Susana Mountain Park Association
Save Chatsworth
Chatsworth Historical Society
Santa Susana Pass State Historical Park