Paleozoic
Overlying the Tintic Quartzite is the Ophir Shale a dark red-brown, deep water sediment. The Ophir Shale is best known at Alta for forming the jagged outcrops above the High Traverse. This rock unit crosses the trail near the end of the High Traverse and when snow depths are low, fragments of these outcrops litter […]
Paleozoic
The bulk of the rocks at Alta, the rocks that we ski on, record the advances and retreats of ancient oceans that occupied this area of North America between 540 and 330 million years ago (Paleozoic Era). The oldest of these rocks is the Tintic quartzite a hard, dense, buff-colored rock that generally forms rounded […]
Proterozoic Rocks
The oldest rocks you will see at Alta form the dramatic outcrops on the southeast flank of Mount Superior on the north side of Little Cottonwood Canyon. These are extremely old rocks (Upper Proterozoic Era, + 800 million years). The lighter brown rocks to the west consist of the Little Cottonwood Formation. The dark brown […]
The bedrock geology of Alta and the surrounding area was mapped by the U. S. Geological Survey in 1943. U.S. Geological Survey, 1943
Proterozoic Rocks
The oldest rocks you will see at Alta form the dramatic outcrops on the southeast flank of Mount Superior on the north side of Little Cottonwood Canyon. These are extremely old rocks (Upper Proterozoic Era, + 800 million years). The lighter brown rocks to the west consist of the Little Cottonwood Formation. The dark brown […]
Paleozoic
The bulk of the rocks at Alta, the rocks that we ski on, record the advances and retreats of ancient oceans that occupied this area of North America between 540 and 330 million years ago (Paleozoic Era). The oldest of these rocks is the Tintic quartzite a hard, dense, buff-colored rock that generally forms rounded […]
Proterozoic Rocks
Proterozoic RocksThe oldest rocks you will see at Alta form the dramatic outcrops on the southeast flank of Mount Superior on the north side of Little Cottonwood Canyon. These are extremely old rocks (Upper Proterozoic Era, + 800 million years). The lighter brown rocks to the west consist of the Little Cottonwood Formation. The dark […]
Bedrock Geology of Alta
The bedrock geology of Alta and the surrounding area was mapped by the U. S. Geological Survey in 1943. U.S. Geological Survey, 1943