It's ambiguous in the film. Karen Allen was 30 when Raiders was made so we could be talking college age which still fits with the dialogue for an affair with a 10+ year older man at that age.
Of course, it's not really remarkable in the film because, in addition to both of them being 10 years older, it's very much a norm in Hollywood to have younger (so long as not too young) women and older men.
Of course, it's not really remarkable in the film because, in addition to both of them being 10 years older, it's very much a norm in Hollywood to have younger (so long as not too young) women and older men.