I agree that Lovecraft was a key influecence, but the name 'Chthon' is not from Lovecraft. It comes from the word chthonic, which comes from khth�n, the Greek word for earth.
Kell wrote an article on this very subject, though he spells my name wrong, AND the name of my website! Anyway, the link is http://www.signsofkoth.co.uk/stuff_lovecraftinquake.html
thanx for the link to the article, a well written and interesting read indeed.
I had never read that article before (honest!). Its also interesting that Kell mentions Giger near the end, just as i did in my post above.
If nothing else... Giger himself has named Lovecraft as an influence. In fact i first learned about Lovecraft by reading through one of Giger's art books -- Arh+, i think.