# Signatures of acid rain at KT boundary

I read in Walter Alvarez' book T. Rex and the Crater of Doom that the Earth's collision with the large meteor leading to the K-T extinction catalyzed the reaction of atmospheric oxygen and nitrogen molecules to form nitric oxide, which in turn formed highly corrosive nitric acid when combined with water. In addition the impact is thought to have volatilized huge amounts of sulfur contained in anhydrite, which in turn formed sulfuric acid.

This question refers to a thickness of $$\pu{1.8m}$$ for the section where iridium could be detected in the K-T boundary, suggesting that the resolution may be too low to note the effects of acid rain following the collision.

Is there evidence in the geological record of the formation of these acid species thought to be associated with the collision, say from deposits and/or effects of the ensuing acid rain?

so the release is $$\approx 1000\times$$ today's annual sulfur cycle.
• I'm sort of thinking out loud here. I see that the oceans are 3% sulfate so the increase in sulfur concentration is negligible in the oceans (1.332 billion cubic kilometers ). (Cubic kilometer $\approx$ gigatonne.) – Keith McClary Feb 27 at 17:58