Libing

Now, they could build a makeshift shelter but it would be unlikely to survive the storm. No, they'd have to find a natural shelter.

The brash boy had already left, likely wandering around aimlessly; but, the old man had other plans.

He walked over to the river he had heard earlier, still gushing. He bent over and cupped his hands to get some water--but, he wasn't thirsty. He sniffed the water.

"Smells like iron." he thought.

He took a sip. It tasted metallic;

"Must have been limestone mixed into the water."

Over time, the flow of water can break down stone to form a cave, and all the dissolved minerals get mixed into the water, giving it a harsh, impure taste.

"Yes... I might find a cave if I follow this river."