Present Day Stress Orientation in Brunei : A Snapshot of ‘ Prograding Deltaic Tectonics ’

The Baram Delta province of northwest Borneo is unusual when compared to other Tertiary deltas, as it has built up upon an active margin. Hence, structures observed in the Baram Delta province are the result of both margin-parallel gravity-driven deltaic tectonics and approximately margin-normal transpressive tectonics associated with the active margin. Image and dipmeter logs have been examined for breakouts and drilling-induced tensile fractures (DITFs) in 46 wells throughout Brunei. Breakouts and DITFs observed in 19 wells suggest that the maximum horizontal stress is oriented margin-normal (NW-SE) in the proximal parts of the basin and margin-parallel (NE-SW) in the distal region. The margin-

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