PRESSURE MELTING

When a rock falls and then rests on a glacier, its weight causes pressure to build up on the ice beneath it. This pressure causes the ice to melt, allowing the rock to sink into the glacier, with the melt water displaced up and around the rock. As the pressure melting continues, the the rock slips further inside the ice. Above the rock, where there is no longer pressure being exerted, the melt water begins to refreeze, encompassing the rock entirely in ice. This process of ice melting of ice due to pressure and then refreezing is called regelation.