Does each core have a similar level of load? Is that just an extreme example, is the ~14 degree difference common?
Do other programs show the same disparity?
It isn't too uncommon for temperatures to vary a bit. I know earlier Wolfdales (like the C0 stepping Core 2 Duo E8400) were infamous for having varying and/or inaccurate sensors. Some CPUs just run that way as well, and the cooler and I think even the orientation/direction can play a part (albeit small).