All articles by Wretch Fossil are here: http://www.wretch.cc/blog/lin440315&category_id=0
There were humans 300 million years ago:
Giant's Causeway was man-made: http://wretchfossil.blogspot.tw/search?q=giant%27s+causeway
In view of the above, Tessellated pavements should also be man-made.
Wretch Fossil’s website:http://wretchfossil.blogspot.com/