Organisers say the event has attracted more than 900 delegates from Papua New Guinea, the Pacific region, Australia, the US, Japan, China and Timor-Leste. The conference's main sponsors include ExxonMobil PNG, Newcrest Mining, Total, Oil Search, the Porgera JV, Ok Tedi Mining, Santos, ANZ, and Spiecapag.
Sharing the podium with Marape in the opening session were Oil Search MD Peter Botten and Ok Tedi's Peter Graham.
This year's event, being held at the Stanley Hotel, has the theme 'PNG resources: developing shared value'.
They were followed by Kumul Petroleum Holdings' Wapu Sonk and Total business director Sangkaran Ratnam.
Also on the program yesterday were the Mineral Resources Authority's Jerry Garry and Barrick Niugini's executive MD Anthony Esplin.
Today, Treasury Minister Ian Ling-Stuckey will speak on the National Budget and the 2020 vision for PNG. He will share the stage with companies updating the status of their oil and gas projects, followed by the miners.
Frieda River, Ramu, Simberi and Hidden Valley are all part of this afternoon's session, with the graveyard shift devoted to training and gender diversity issues.
Tomorrow will be the turn of the junior miners, with John Lewins (Kainantu), Ron Heeks (Woodlark), Andrew Corbett (Misima) and Wanfu Huang (Coppermoly exploration) telling their stories.
The mining juniors will be followed by oil and gas exploration updates from Twinz, Kina, Oil Search and ExxonMobil.
Thursday's program will end with a ministerial address by Petroleum Minister Kerenga Kua, followed by a panel session on the 'business perspective on shared value for PNG'.