The country was moving.
She registered the lateral roll first, the long low-frequency sweep of a shallow karst release somewhere east-northeast of the saddle, and her body — which had been listening to the earth’s interior since 2008 — read the magnitude as the magnitude landed, and the magnitude was a six, possibly a six-point-two, with a hypocenter shallow enough that the roll was traveling through the limestone of the country at the speed and amplitude of a near-field event, and the limestone of the country was responding the way Triassic carbonates with old solution voids and recent reactivation along bedding planes responded to a near-field magnitude six, which was to fail at the weak structural points, and the weak structural points of this particular saddle, which she had read off the topo at the bench fifteen minutes ago, were the mass-wasting margins on the canyon-side of the trail.
Paul’s right hand was on her right shoulder.
His left hand was at the small of her back.
She was being moved off the trail and into the lee of the dead pine, not lifted, not pushed, just moved with the smooth direction of a hand on her shoulder and a hand at her back and the fast sequence of a man who had been getting people out of the line of failing terrain for fifteen years.
The pine they had been sitting under thirty seconds ago was no longer under them.
The pine was twenty meters above them on the saddle.
The ground had moved twenty meters.
Or — her body knew it as her mind was naming it — the ground had not moved twenty meters. They had moved twenty meters. The slope below the trail had failed. The slope had failed in the predictable way Triassic carbonate slopes failed under near-field magnitude six events, and a section of the trail and the bench and the limestone shoulder above the canyon-side mass-wasting margin had separated from the saddle and was, at the moment her body caught up to it, sliding.
The sliding was not a fall.
The sliding was a slow rolling translation of about thirty cubic meters of saddle material on a bed of failure-plane debris, moving down-slope at less than a meter a second, with Iris and Paul on the upper surface of the moving mass and the canyon below them and the morning sun on the limestone and the dust of the slide rising into the air around them, and under all of it a low grinding roar she heard less with her ears than through her sternum.
She heard Paul say, “Doc.”
She heard herself say, “I am here.”
She heard Paul say, “Stay low. We are riding this. We are not jumping.”
She heard herself say, “Copy.”