Please note..David, from World Book Dictionary
TSUNAMI
Quote: an oceanic tidal wave caused by a submarine earthquake or volcanic eruption [Japanese tsu = harbour, + nami = wave]
Yes I did mean tidal wave - ie one tide brought millions of tonnes of trees (stripped from the rainforest) and dumped them - say - in a valley in Wales. The next tide delivered more trees, then silt, then dead animals.
Then under great weight, those trees turned into coal
Possible???
What caused these monster tides??? Good 'ol Mars HA HA