Alberta, Rocky Mountains, Deltaform Mountain
At 6:30 a.m. on August 18, 1981, four men began an ascent of Deltaform Mountain via the north glacier route. By noon they had gained the rock rib above the most difficult ice. They left the ice and climbed right out onto a rock rib below a steep rock prow to have lunch. As they started to move back onto the ice, a massive rockfall occurred from approximately 1,000 feet above them. One climber was hit on the head by a falling rock and suffered head injuries. He complained of tingling and numbness in the head, neck and arms. He was evacuated by a rescue team using helicopter sling techniques. (Source: C. Israelson, Banff National Park)
The lives of the entire party were saved by stopping for lunch under a steep face that offered protection. Most of the rocks passed harmlessly overhead, with only a few of the smaller ones striking the climbers.
In the Canadian Rockies, gullies and ice chutes are prone to natural rockfall and should be avoided when possible. If such a route is chosen, all possible efforts should be made to use the terrain for protection from falling rocks. (Source: C. Israelson, Banff National Park)