The Penyu Basin, situated offshore eastern Peninsular Malaysia, stands as the smallest among the Cenozoic extensional basins within Sundaland. The basin has sedimentary thickness reaching up to 9 km (Figure 1), filled by predominantly Oligocene-Miocene successions, transitioning from lacustrine at the base to fluvio-deltaic and shallow marine environments in the younger section. Despite exploration efforts since 1970’s, only 17 wells have been drilled, signifying the relative under-exploration of this basin (Madon et al., 2019). The hydrocarbon potential and working petroleum system of the Penyu Basin has been proven by several wells, however, the scale of discoveries remains sub-economic (Madon et al., 2019). This paper provides a concise overview of our integrated efforts in the data enhancement and studies, illustrating how they have contributed to a more refined geological and geophysical understanding of the area.

PETRONAS, in collaboration with industry experts, spearheaded an integrated effort aimed at revisiting petroleum system modeling, reprocessing selected 2D seismic data, and conducting Amplitude Versus Offset (AVO) evaluations. In addition to our collaboration with established industry experts, PETRONAS has formed close partnerships with the leading universities. A recent collaborative effort focused on evaluating the potential of Pre-Tertiary carbonate play in the Penyu Basin. This study leveraged existing seismic surveys, complimented with non-seismic datasets, including Full Tensor Gradiometry (FTG), aeromagnetic, and satellite gravity data. This comprehensive project yielded significant insights into the untapped hydrocarbon potential, including shallow gas, syn-rift margin ramps, fractured Mesozoic formations and Pre-Tertiary carbonate within the basin (Figure 2).

These endeavors have proven instrumental for PETRONAS in identifying underexplored potential, offering compelling new insights that can significantly enhance the basin’s attractiveness for future exploration or area promotion. PETRONAS is also initiating a new 3D seismic program alongside an integrated source-to-sink study, to facilitate a seamless evaluation process, contributing to a more refined understanding of the area.