oa New Insights on the Structural Configuration and Evolution of the Deepwater Offshore Margin of Sabah

Offshore Sabah has a complex history, from the pre-rift Mesozoic to the Miocene and recent times. Here we present a model for the tectonic evolution of the deepwater offshore Sabah region based on recent observations on seismic and structural restoration of semi-regional lines through the Sabah trough and the Dangerous Grounds. We will illustrate the tectonic controls on the basin architecture, fault style, the timing of events and implications in terms of petroleum systems and prospectivity.

The area experienced rifting starting in Palaeocene- early Eocene, until the Breakup Unconformity in the Oligocene. At the end of the rifting there is evidence of volcanic activity around volcanic centers. Then starts a sag phase and the buildup of carbonate mounds on topographic highs. Subsidence continues in the Sabah trough during the Miocene and a fold-and-thrust belt starts forming to the SE of the Sabah trough. This drowns the carbonate mounds at the edge of the trough and a more siliciclastic sedimentation takes the relay in the trough. In this work we also look at the early configuration of the basin and fault systems involved, as well as the inversion episodes recorded on this part of the margin.