In early spring, the Alberton Gorge is a high adventure, big water raft trip. As the summer warms up and the water drops , the individual rapids of the Gorge emerge, and dozens of Class I-III gems – such as Triple Bridges, Boat Eater, Tumbleweed, and Davey Jones’s Locker – are revealed. Remarkably, the Gorge offers fantastic whitewater rafting all year long!
ZOO TOWN SURFERS HEADQUARTERS
Our headquarters, Crystal Springs, is right off of exit 65, on HWY 90, and overlooks the Alberton Gorge. Only 5 minutes from the put-in and take-out, making last minute trip changes, shuttles, and river access simple and easy. Crystal Springs is an ideal location for post-float barbeques, family reunions, and company outings. Crystal Springs is fully equipped with hot/cold showers, clean bathrooms, horseshoes, warm/cold beverages, and a retail shop. Go rafting, then kick back, relax and enjoy some homemade salsa and a cold beverage on one of our decks overlooking the Alberton Gorge. Stop by and see us! We’re here every day, all summer long.
ALBERTON GORGE GEOLOGY
The Belt Supergroup (Belt rock) is a collection of mostly fined-grained sedimentary rocks. The sedimentary rocks that from the Beast Supergroup were formed in the Precambrian (Mesoproterozoic) age (1 billion to 1.6 billion years ago – WOW!). The Mesoproterozoic was the first period of Earth’s history in which a good geological record still survives.
The current theory is that an inland sea (slightly similar to a small Mediterranean Sea) existed in the North American Craton (Craton – the ancient geological core of the North American Continent), and the deposits in this sea form the Belt Rocks. Some cool features (geologically speaking) of the Belt Rocks:
Some cool features (geologically speaking) of the Belt rocks:
- Ripple marks (from waves in shallow water) exist in the formation. This is rare because of the great age of the Belt rocks (usually these structures are destroyed by metamorphosis or other geologic processes).
- They contain no obvious, visible fossils of plants or animals. There is evidence of extremely primitive plants and bacteria, the rocks offer no trace of animal life. This is thought to be because very little life existed on Earth at this time except for life in the ocean….and the inland sea that formed these rocks was not connected to the ocean.
- Mudcracks are abundant between layers of Belt rocks; These were caused by surfaces that dried in the sun before being flooded by water that brought more mud or silt, which preserved the delicate features.
- Many of the layers of mudstone in the Belt Supergroup are colored interesting shades of green or reddish purple. The red, purple, and maroon color is due to the red mineral called “hematite” formed as iron reacts with oxygen from the atmosphere. It is believed that the green rocks were formed in deeper water where oxygen was less available. The alternating green and red layers suggest fluctuations in the depth of the Belt Inland Sea.
During the last ice age, approximately 20,000 years ago, the Clark Fork Valley rested along the southern edge of the Cordilleran Ice Sheet, which covered much of western North America. The ice sheet advanced and formed a frozen dam on the river, creating Glacial Lake Missoula, stretched across the Clark Fork Valley and central Montana. The periodic rupturing and rebuilding of the ice dam released the Missoula Floods, a series of catastrophic floods which roared down the Clark Fork and Pend Oreille Rivers and into the Columbia, sculpting many of the geologic features you see on the Alberton Gorge today.