OK, AM. we may have confirmation of sorts that Jane was indeed in Iceland even if Natalie Portman was not.... (per what I was suggesting earlier about long shots being done of them travelling and so Natalie not needed in Iceland for that reason)
http://www.castingcallpro.com/uk/view.php?uid=271384
She is also listed as Natalie's double in IMDB, notice after Thor the Dark World at the end Company/Venue it says Marvel Studios UK/Iceland