Sparse lodgepole pines had rooted in the cracks wherever soil had accumulated, their trunks growing at odd angles as the rock beneath them shifted across the years.
At 9:40 in the morning, one of the investigators, a 34year-old NPS special agent named Tomas Guerrero, who had joined the investigative services branch 4 years earlier after a decade with the FBI, located an anomaly in the rock face approximately 22 m below the ridge crest.
It was a horizontal crack between two large riolyte slabs approximately 3 ft wide and [music] 18 in tall partially oluded by a third slab that had shifted inward from the left creating an irregular triangular opening.
The opening exhaled air that was measurably warmer than the ambient temperature. Agent Guerrero estimated the difference at 12 degrees using a digital thermometer and that carried a stronger sulfur compound than the surrounding area.
A thin orange brown mineral stain framed the upper edge of the opening consistent with the stain in the second recovered image.
