STRUCTURAL TRAP MODELLING OF THE BIAK-YAPEN BASIN AS A NEOGEN FRONTIER BASIN IN NORTH PAPUA

摘要

The Biak-Yapen Basin is a frontier basin located in offshore Northern Papua New Guinea. The results of gravity and magnetotelluric's measurements shows an indication that the sediments thickness reach >2000 metres with a density value of 2.45 gr/enr and resistivity' value between 0-60 Dm. The presence of candidate petroleum system rocks can be analogized as ideal surface data is found in the northern and southern Neogen-Supiori track segment. This segment is characterized in the Wainukendi Formatian and Wafordori Formation with a black shale and carbonaceous claystone as a source rock and are candidates as reservoir rocks derived from sandy limestones and candidates as sealing rocks derived from silty limestones. The 78 stations measurement of structure along the Biak track segment showing a stress horizontal minimum (Shmin) is 7 stations intensity with NE -SW oriented, 6 stations directed at ENE - WSW and 8 stations directed at NE-SW. Shmin also can be known from the stress regime in Biak trajectory segment which is categorized as transtensive regime with 47,40% intensity. The Neogen-aged hydrocarbon trap model of the Biak-Yapen Basin which is based on the geological modelling surfarce analogy and geophysical cross section in Biak Island and Supiori island can be assumed as a structured trap. It is estimated to be trapped in the hanging wall and foot wall of the fault structure. Hydrocarbon is predicted to have accumulated between the depths of 1000 meters to 3000 meters.