No Frictional Heat on the San Gabriel fault, California:
Evidence from Fission-Track Thermochronology
Matthew A. d'Alessio, Ann E. Blythe, and Roland Bürgmann
Directions to the Earthquake Fault Locality
View of the parking area at the Earthquake Fault site. Note: you don't have to get this high above the parking area to view the fault. The best viewing is at the base of the cliff just to the right of this photograph.
GETTING THERE
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- From the intersection of Interstate 5 and Interstate 210,
- Travel about 7.5 miles East on 210
- Take the OSBORNE ST exit
- Head Northeast on FOOTHILL BLVD (LEFT, if coming from I-5, RIGHT if coming from Pasadena)
- Turn LEFT on OSBORNE ST and head north
- OSBORNE ST becomes LITTLE TUJUNGA CANYON RD
- In general, follow the signs to the Wildlife Waystation, which you'll pass on the way to the Earthquake Fault Locality.
- Head up the hill all the way to the top. A few hundred meters before you get to the Dillon Divide (at the top of the hill), you'll pass the San Gabriel fault for the first time.
- Follow the road back down the hill. You'll wind through the valley over a small bridge and pass several rural residential homes.
- When the road begins to climb back up again, be on the lookout for a picnic table and a trash can on your right. They will be at the apex of a hairpin turn. There will also be a big sign with a fault map of California. Park here.
- When facing the sign, a small trail should run up a dry creek filled with boulders to your right. Follow it less than 20 meters. The fault is exposed on the steep face (on your left as you walk away from the parking pullout) to the south of a dry waterfall.
- A branch of the fault runs underneath the dry waterfall, but the most dramatic viewing is about 5 meters to the south of the waterfall. To spot the lithologic contrast, it helps to walk up the small landslide slope to your right as you walk away from the parking pullout. Then, look back towards the dry waterfall and the cliff face and you'll see the bright white granitic rock on the left and a darker gneiss (the same rock as under the dry waterfall) on the right.
- Be on the lookout for POISON OAK, which is present at the site year round!
- NOTE: In mid-2005, the picnic table and trash can were not there anymore, though the concrete slab where the picnic table once resided is still there. The sign with California faults was still there.
PERMIT
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Technically speaking, you need a US Forest Service Adventure Pass to park anywhere within the National Forest. They cost $5 a day.
http://www.fs.fed.us/r5/angeles/passes/pass-adventure.shtml
M-F 8:00 am - 4:30 pm, you can stop off at the Los Angeles River Ranger District Office about 1.5 miles up the road from the Freeway. It's on the left and I think it kind of sneaks up on you. At other times, you'll have to get one at one of the vendors shown on the web site.