There is a patch of land in Ventura that is heating up. The property is over 800 degrees and has reached these temperatures on and off during the last 30+ years.
The LA Times has a story here, no pictures.
https://latimesblogs.latimes.com/lanow/2008/08/ventura-county.html
Smoking mainly because the ground is so hot, there could also be a danger that the brush on the property could ignite, so the fire dept. in Ventura is doing daily checks on the property.
I wonder if this is the only area with this type of geothermal activity. There was some talk about this in the Mammoth area, where trees have been dying off.