Rio Tinto executives could face harsher punishment for destruction of Juukan Gorge within days, after investors made clear over the past two weeks that the financial penalties handed down were inadequate.

This week, Rio's board of directors are expected to discuss an escalation of the company's response beyond cancelling executive bonuses, leaving open the possibility that some might face dismissal or demotion over the destruction of 46,000-year-old Indigenous heritage in Western Australia.