We know about the KT extinction layer (which contains a lot of iridium, a potentially extremely useful but rare metal) but attribute it to meteorite ejecta. It

We know about the KT extinction layer (which contains a lot of iridium, a potentially extremely useful but rare metal) but attribute it to meteorite ejecta. It also coincided with large scale climate and environmental changes. That's the only candidate I know of as a non-geologist.