 FACT: When Annie and Elliott are in the crevasse, Annie crosses to  get the pack frozen into the wrong. She brings the pack back over  and is checking the supplies. One of the items, a flask, she shakes  and you can hear there is liquid still inside it. Even with the  effects of a vacuum flask, the contents would have frozen,  especially considering this pack was frozen into the rock indicating  it had been there for some time.