OCR Text |
Show Approximately 5k miles west of Denver, Colorado, Bethel Mountain overhangs transcontinental highway ü. S. 6. A large avalanche chute with an SE aspect produces very large snow slides at least once a winter on to the highway. The snow satchment basin is a large área where a tremendous volume of snow accumulates at the release point of the avalanche. When the catchment basin discharges its load of snow the avalanche splits into two distinct chutes. At the lower third of the slide path the snow comes together again and descends in a single chute in which large volumes of snow are moving at extremely high speeds toward the highway. The slide path is approximately 1 mile long. Width ranges from 3000 ft. at the deposition zone to 400 ft. in the center of the slide path to 1500 ft. in the lower transition above the highway. When the avalanche discharges in large proportions the snow covers the highway to a depth of 15 ft. for an área 1500 ft. wide. Some snow continues on across the highway for a distance of * f00 to 500 feet, finally coming to rest against the opposite slope. Assuming that the average width of the slide path is 1630 ft. and the length is 5280 ft. while average depth of snow involved when released is 6 ft., the volume of snow involved exceeds 50 million cubic ft. Making a further assump-tion that the average density of the snow at the time of release is 20516 ( 12.5 lb/ cu ft) it is seen that the total mass of snow that overruns the highway can exceed 310,000 tons. |