Ms Noonan, from Co Clare, was living and working in Annonay as an English language teacher.
Police in Lyon and Annonay are both involved in a search operation to find her.
She is not believed to have a wallet, purse or ID on her.
Riders moving on to East final after 31-20 win over Ottawa
Kienan LaFrance with two catches for 26 yards would set up Kevin Glenn for the one yard plunge making it 14-8 Saskatchewan. Ottawa countered at 4:07 with Harris's 56-yard TD pass to Spencer before finding Criner on the two-point convert.
Eimear hasn't been since Wednesday, and had not informed work she would be absent.
She was described as a "warm, bubbly person who had already made a wide circle of friends there through her love of music and singing".
"She graduated last month from UCC with an honours degree in Irish and French, was a talented violinist and to our vast pride was head of the UCC orchestra for her final year there".
"My younger sister Eimear has gone missing in Annonay, France, half an hour outside Lyon", one family member wrote on Facebook.