High-Resolution Sequence Stratigraphy and Paleogeographic
Evolution of the Middle Miocene Gas-Bearing Successions in Northern
Mohamed Som, Mohd Rapi1, Abdul Hadi Abd Rahman2, Moh’D. Nurein Bushara3 (1) PETRONAS Research Malaysia, Bangi, Selangor, Malaysia (2) Universiti Sains Malaysia, Penang, Malaysia (3) PETRONAS Carigali Sdn Bhd, Kuala Lumpur, Malaysia
High resolution sequence stratigraphic analysis and interpretation, based on the facies description, log analysis and paleoenvironmental
interpretation, identified major sequence boundaries and sequences within the E
and D Groups (Middle Miocene) of the northwest of
The succession of sequences of the E-D-B Groups is the product of multiple cycles of relative sea-level fall and rise onto an incised valley. The E Group forms the Early Transgressive Interval, and comprises at least five high-frequency sequences (4th order?) of LST-TST-dominated, fluvial sequences. The Late Transgressive D Group was deposited as the result of relative sea-level rise. The inundation of the incised valley resulted in the development of an estuary at the beginning of Sequence D1, reaching its maximum size during the deposition of Sequence D5. The Regressive Interval (the HST) of the incised valley is partly or completely absent. It may have been eroded during the rapid regression marked by the fluvial-dominated, delta-forming system of the B Group. These paleogeographic facies models and sequence stratigraphic interpretation may be utilized as working models for future well planning.