Soot

[I originally wrote this in October 2011, but never posted this series on the local geology. The pictures are still worth seeing. The Las Conchas fire burned Santa Clara canyon in 2011.]

This morning I walked to the far arroyo for the first time since Wednesday’s rain. Everywhere there were signs of the Las Conchas fire.

When I entered below the ranch road I saw black soot laying in water paths left on the bottom.

As I walked up stream I saw the charcoal trails along the low left banks. As I came back down, they were also on the right side, swirling along the base of the high walls.

I could only think it’s a Goldilocks situation. Earlier this summer, when water scoured the bottom of the arroyo, it was passing through so quickly it left little behind. Other times, the rain was so gentle it only moved silt a few feet. The traces of black were slight.

Wednesday it rain most of the day and much of the night, a gentle rain that soaked in. I’m guessing that it washed a layer of sand from the surface of those blocks I noticed earlier where it had accumulated and the soot and sand landed somewhere down stream.

Upstream, there must have been other patches of ash waiting to move. Each time this year when some ash moved from higher up the arroyo, it replaced some that had been washed down stream. Perhaps it had slowly become concentrated in areas near the main water paths. Finally, there was enough rain to collect it and move it slowly where it could drop between Wednesday’s showers.

The fire was suddenly visible everywhere again.