Crevasses

Crevasses are deep fissures or cracks formed on snowfields due to varying glacier velocities. More the speed with which a glacier moves down, more are the chances of extension and formation of a crevasse. Crevasses can be of various types-transverse crevasses, marginal crevasses and longitudinal crevasses. Stretching across the full glacier, transverse crevasses are the most common types of crevasses. Marginal crevasses are formed due to the pressure of the glacier at the center rather than at the margins, these crevasses reach up-glacier by extending diagonally from the edge of the glacier. With expanding glacier width, longitudinal crevasses are formed.

Crevasses are notoriously renowned for gulping down skilled skiers and highly skilled travelers. Training is provided to skiers and travelers in rope rescue techniques prior venturing out on skiing and trekking expeditions. Depths of the crevasses can reach up to 30meters or more and the width also varies depending on the mass of the glacier and snow. Rescue from crevasses can be done by trained crevasse rescuers. The initial action to be taken if an individual slips into a crevasse is to stabilize the total situation and make everyone panic free. The next step involves pulling out the person from the crevasse with the help of a rope. Many a times single pulley technique is also applied to pull back the victim to the ground. Prusik knots with slings can be used by the victim to ascend the rope if he/she can move in the crevasse. Though rescuing from crevasse seems to be an easy job, but practically is very painstaking and dangerous.