Brad has sparked my interest in gathering some detailed geologic info on the Pinns.
I found a few resources so far, including an online interactive geologic map. To wet your appetites I took a screen shot and did some extra labeling of "local" faults since the resolution/zoom capability of the map is limited. I am really digging the fact that it looks like the Pinnacles Fault slices through along the base of the Mighty Machete. I was already aware of the Chalone Creek Fault and the nice stratigraphic section you can walk and map up Condor Gulch, but the Miner's Gulch Fault is new to me and now I am hungry for more info. I'll post links, pics and various info as I quest for knowledge. This is GOOD STUFF!!!
You'll notice the Chalone Creek and Miner's Gulch Faults are parallel to the SAF. Some geologists speculate that the Chalone Creek Fault is an ancient trace of the SAF - showing its migration east through geologic time.
