All posts by Michael F Ballard

Michael F Ballard is the author and administrator of the Southern California Regional Rocks and Roads website, https://socalregion.com, since 1995. I have been studying the geology and highway history throughout southern California for most of my life. I am also the President of the Ridge Route Preservation Organization. Founder of the Historic Highway 99 Association of California, https://historic99.org .

San Diego Fossils

I’ve been doing a bit of work lately on my geologic study of central San Diego and have found many fossil sites. So far, none of the fossils have been very complete. Mostly shell fragments in condensed layers. The oldest found so far have been from the Eocene Mission Valley Formation, which is between 40 and 48 mya.

Small shells within the Mission Valley Fm in Presidio Park.

In addition to the fossils found in Presidio Park, I have also found a few locations around Hillcrest and South Park. Some of these are just the side of the road, others you have to hike a bit in a canyon.

Fossil shells (mostly bivalves) within the San Diego Fm.

Underlying the southern half of the central San Diego Mesa is the San Diego Formation, which is late Pliocene to early Pleistocene in age, about 5 to 1.5 mya. It has many layers containing fossils, such as the one pictured above.

Once you get the “eye” for fossils, they seem like they pop up everywhere. It would seem that every time I go out on my mapping project lately, I find fossils. Geology can be a lot of fun and I encourage all interested to go out and explore their local area. You never know what you might find.

Ridge Route Update

Representatives from the Ridge Route Preservation Organization, including myself, recently met with a few people from the Angeles National Forest regarding the Ridge Route. A summary of the meeting can be found on the ridgeroute.org site – http://www.ridgeroute.org/june-2019-update/ .

Geologic Report

In January, I was asked to do some research regarding the potential for a landslide on the Ridge Route near Templin Highway. I thought it would be a good opportunity to get some practice writing a geologic report. While I’m not a professional geologist, I still find it a lot of fun to do . I added a copy of the report on this site, available for download. I would love to hear feedback from any other geologists out there.

Ridge Route Geology Study – Preliminary

Featured Image – 3/30/2019

Old US 60 / 70 in Chuckwalla Valley between Desert Center and Blythe.

Site Update – HTTPS

This site is changing to https instead of http. I’m hoping that the changes I have made to the files are working properly and will redirect to the https version of the site. If you’re experiencing trouble, please let us know.