Gordon joined Chrysalis in 1994 as corporate development director, becoming, at 28, the youngest woman to join the board of an LSE-quoted company.
She announced this week she was to leave the company to spend more time with her young family.
The investor relations aspect of her brief has passed to Harriet Finney, who joins in January in the newly created role of investor relations manager.
She will not have Gordon's board level status and it has not yet been decided whether she will have corporate comms responsibilities.
Finney, who joins from Orange where she has the same title, will report to Chrysalis CEO Richard Huntingford.
Announcing her decision to leave, Gordon said: 'The time is now right to do what I've been promising myself for ages, to spend some time enjoying my children while they, and I, are still young.'
She leaves at a time of recovery for the media group, which turned around pre-tax losses last year of £16.8m to profits of £5.8m this year.
This week the group, which owns Galaxy, Heart 106.2 and LBC radio stations, also announced a 17 per cent growth in ad revenue.