Hi All. I have a question on this subject. I'm sure there are plenty of people on the board who can give some good answers. I just watched a documentary about the Tunguska event on the UK tv channel More4. It was actually fairly disappointing (it focused more on the investigators involved than on the science of the event), but there was one thing that puzzled me. There were a couple of scientists from Italy that were taking photographs of the bottom of Lake Cheko, which they suspected was formed by a fragment of the body that exploded. They were happy to find tree stumps on the bottom of the lake, which I understand showed that the formation of the lake was a recent event. My question is this: If the lake is a flooded bolide impact crater, why would there be trees preserved at the bottom of it? Wouldn't they have been destroyed utterly when the crater was excavated? Thanks for your attention. PS: Apologies if this has been posted in the wrong place. Please feel free to move it somewhere more appropriate.