The survey will form part of a regional group shoot using the Veritas Geophysical ship, MV Veritas Voyager.

Covering 9150 square kilometres, the service contract hosts the Marantao Reef Prospect, with mapped closure of more than 150sq.km. Marantao is about five times bigger than the Shell-operated Malampaya oil and gas field, which is geologically similar and on trend.

Otto estimates that that the structure has the potential to host 500-750 million barrels (MMbbl) of oil, or 2.5-4 trillion cubic feet of gas.

“The commencement of the offshore seismic survey over the giant Marantao prospect marks the start of an exciting new phase in Otto’s short history,” the company said.

“With new seismic over Marantao, the company will be in a position to invite oil majors to join it in its deepwater search in the Philippines.”

Otto currently holds a 55% interest in SC55 through its wholly-owned subsidiary NorAsian Energy, in partnership with Trans-Asia Oil and Energy and Vital Resources.

Nearby in its half-owned SC51, Otto said an engineering study is underway on the Villaba-1ST gas discovery well, located in the northern part of the permit, to determine its commerciality.

Additional geophysical mapping will be undertaken on 250km of seismic currently being reprocessed to identify additional gas resource potential in three satellite reef structures immediately neighbouring the Villaba gas discovery.

Meanwhile in SC50, Otto says it has resumed detailed well planning and design for the re-entry/horizontal drilling and extended well test of the Calauit-1B oil field.

Independent consultant Dr Andrew Wadsley has determined the Calauit-1B oil field has the potential to contain 39.5MMbbl of oil in-place, of which 6.44MMbbl are considered recoverable.

Otto holds a 65% stake in SC50.