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 .

University Heights – 1888

San Diego has changed quite a bit since it was first laid out in the late 1700’s. As the city grew, new neighborhoods were planned farther out from the city center. One of these, University Heights, is still around today by the same name albeit covering a smaller area. The original plan, from 1888, was mostly built and is still quite recognizable today. One major item, a lake known as Mystic Lake, was never constructed. Today, the canyon remains undeveloped and is considered public open space. In addition to the lake,

The map also shows a small section of right-of-way for a railroad just east of Park Blvd. This railroad, the University Heights Motor Road, was built as a way to bring prospective buyers from downtown to East San Diego (later City Heights). It was dismantled not long after construction but traces still remain on maps and in Switzer Canyon.

The name, University Heights, stems from a planned university that was to be sited there. A small teacher’s college, which later became San Diego State University, was indeed located there. In the 1950’s, the structures were mostly torn down except one which remains today. The site is the headquarters for the San Diego Unified School District.

1888 Map of University Heights, San Diego, CA

Seismographs Online

The California Integrated Seismic Network has an online feed showing seismographs throughout southern California.

http://www.scsn.org/index.php/earthquakes/live-seismogram-feed/index.html

Earthquake UPDATES – Mw 7.1 near Ridgecrest

Well, that was strong! I felt it here in San Diego. First time I felt my building sway and it shook for a while. USGS is now reporting the quake as a Mw 7.1, which is 11 times larger than the one yesterday. This, assuming a larger one doesn’t happen, has also been deemed the “main shock” and the 6.4 was the “fore shock”. USGS and Caltech are a bit slow right now. If you felt this one, please let USGS know once their servers are not slow or not working. They need your help!

From Caltrans and CHP, damage reports are coming in of rockfalls on 178 in Poison Canyon, a sinkhole on 178 near the Trona Pinnacles turnoff, and buckling up to 4 feet as well as large cracks in other areas. Do not drive fast through any of the earthquake affected areas. Also be aware that rockfalls will be likely in all the local mountain ranges, so be careful. State 127 near Ibex Pass is covered with rocks, and that is a fair distance away from the epicenter.

http://scedc.caltech.edu/recent/
Working map of all earthquakes in California and Nevada by Caltech. Links to USGS as well on the page.

USGS site now working!
https://earthquake.usgs.gov/earthquakes/eventpage/ci38457511/executive

M 6.4 near Searles Lake, CA

Seismic activity map of the Ridgecrest / Searles Lake area as of 12:40 pm July 4, 2019.

At 10:33 am this morning, July 4, 2019, there was a Mw 6.4 earthquake centered a few miles northeast of Ridgecrest, California. The focus of the earthquake was mid-range in depth, about 10.7 km deep. So far, there have been numerous aftershocks ranging up to M 4.7 in size at the time of this writing. The earthquake is the largest to strike southern California in some time. The area to the northwest of the epicenter has been subject to earthquake swarms in the past as well, though usually only up to the M 5.0 range in size.

Shakemap from this morning’s earthquake

https://earthquake.usgs.gov/earthquakes/eventpage/ci38443183/executive
USGS summary of the earthquake

Due to the size of the earthquake, I would expect there to be a fair amount of damage to buildings in the Searles Lake, Trona, Pioneer Point, Ridgecrest, and Inyokern areas. If you live in any of these areas, let the USGS know about what happened. Your information is greatly appreciated and will help them better understand the effects of earthquakes.

https://earthquake.usgs.gov/earthquakes/eventpage/ci38443183/dyfi/intensity
Did you feel it? Report it to the USGS here!

Adopt-A-Highway Cleanup

Well, it has been a while but I finally made it back up to Grapevine Canyon for a more formal cleanup. I, and two others, cleaned up the upper and lower water stops along I-5 in Grapevine Canyon on Saturday, June 29, 2019. We filled nine bags and found many interesting items including a printer/copier. Next cleanup should be in early September most likely.

Lower water stop – four bags
Upper water stop – five bags and a lot of debris