human
Produce a detailed written description of a risky scene outside a gorge with vertical walls and marbleized limestone.
assistant
A large stream, or perhaps a small river, has carved a deep, narrow gorge into the native sedimentary stone here. The walls of the gorge are almost vertical and provide no purchase. In places, the limestone walls turn to glassy marbleized outcrops, as though some intense heat or force had crystallized or fused the rock together. Such patches make it impossible to climb your way out.