Here is information on the Holocene Start Impact Events

The platinum is no surprise.

ttps://www.youtube.com/watch?v=TbM4vHcRyz0&t=11s&index=8&list=PLQFjoWZeHDMQln37vSd1heFOfte_O_Rhp

http://archaeologica.boardbot.com/viewto...

http://archaeologica.boardbot.com/viewto...

Many people died in the climate collapse following the second impact.

There were several "advanced" societies that dispersed, not just one.

Any maritime people who made dugouts from very large trees were perfectly capable of moving large stones of the same weight.

The current discussion is focusing on how fast neutrons are produced in large hyper velocity impacts.