Non Structural Traps in the Miocene Sedimentary Succession of the Phu Khanh Basin

Summary “Phu Khanh Basin is situated along the narrowest part of the Bien Dong Sea’s shelf and considered as a prospective petroleum basin. Stratigraphic evolution and structural analyses of the Phu Khanh Basin indicate that is a rift basin. Thick sequences of lacustrine and alluvial sediments were deposited during the Paleogene rift periods. The Late Oligocene rifting ended due to inversion, triggered by right-lateral wrenching. Following the onset of this in version regional uplift and volcanism took place in the southern half of the study area and contemporaneous subsidence and transgression took place farther north, leading to wide spread carbonate deposition. As the right-lateral wrenching decreased during the early Neogene, thermal subsidence and siliclastic sedimentation became dominant, resulting in the buildup and south ward propagation of the shelf slope. Sediment accumulation and subsidence rates increased after the Middle Miocene times due to east ward tilting of Central Vietnam. Very large and rapidly sediments deposited within the tectonic development have generated a various type of non structural traps with potential reservoirs including sand bodies, turbidities, and carbonates buildups as well as reefs. These non structural trap plays an important role in Oil and Gas exploration in the Phu Khanh Basin.”