Two children, aged 10 and 12, who were also on the same ride, survived the accident on Tuesday when their raft flipped.
Dreamworld's chief executive, Craig Davidson, laid a wreath yesterday (wed)and has promised to help the two young survivors.
"These children will have our full support into the future. More broadly we recognise this event has affected the entire Dreamworld family, our local communities, our guests and the emergency services and other first responders."
A private ceremony for staff, friends and emergency services who were at the scene will also be held on Friday together with grief counselling for those at the park at the time.
Dreamworld says at the time of the incident the park was fully compliant with all required safety certifications, and that details of an external audit undertaken last month will be provided to the Coroner and workplace safety investigators.