Rising bodies (plutons) of granite disturbed the belts of subducted rock in the Sierra starting in the Cretaceous around 140 Ma, at about the same time as the Franciscan Complex to the west was being subducted. In the High Sierra the granite is nearly the only rock, as we will see at stop 23. Here granite of the Grizzly Pluton is in contact with older metamorphic rocks of the Central Belt, and the area of contact mixes these rocks at an intimate scale. Thick veins, emplaced late during this process, are visible in the rock wall above the tunnel, a sign of the complexity of granite magmatism.
On the left is a small hydroelectric dam, one of several on this stretch of the North Fork Feather River.
Day 1, Coast Range: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9
Day 2, Sierra Nevada: 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18
Day 3, Sierra Nevada: 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28