The pass is the major geologic divide between the igneous batholithic Peninsular Ranges and the Transverse Ranges, which is a massive fault block composed of diverse forms of rock. According to Yule 2009, the pass is the single largest discontinuity along the San Andreas fault. One active branch of the San Andreas Fault passes through the San Gorgonio Pass roughly parallel and just to the north of interstate 10. Active parts of the Banning, the Garnet Hill and the San Gorgonio Pass Thrust faults are associated with the San Andreas Fault through the Pass. Together, these faults accommodate strike-slip and reverse slip that contributes to both uplift of the San Bernardino Mountains and overall movement between the North American plate and the Pacific plate.