Thanks for your post, it's still a current topic of research for me as well.
I come from Central Europe, from Czechoslovakia, from the Krkonoše mountains, which are located in the northeast of the country. We've been finding petrified trilobites and petrified wood in these mountains since we were kids (no one ever thought about how wood could be petrified when normally wood rots and decays - hahaha). In addition, there is still sea sand in the soil deposits in the mountains, especially in the deep woods, you can tell. Near where I lived are the Prachovské rocks - they show clear signs of water washing - dents (the wind makes horizontal lines), so there must have been a sea or ocean and a silicon-based environment (fossilized wood and organisms) in the central European area.
But no one thinks about it at all and it MUST NOT be taught in schools - that's what a teacher told me in elementary school...

Yes - so true - must keep all the people ignorant. In North Georgia USA, there are trilobite fossils there also. It definitely was a global event but it I believe that it was much more recent than we are taught. Not millions of years but maybe ten thousand years or less.