PLIOCENE TO RECENT STRATIGRAPHY OF THE CUU LONG AND NAM CON SON BASINS, OFFSHORE VIETNAM

Chris Yarbrough, Texas A&M University, Department of Geology & Geophysics, College Station, TX 77840, [email protected]

The Cuu Long and Nam Con Son basins are located offshore from the present-day Mekong Delta. The Cuu Long Basin has been in its post-rift stage of development since early Miocene time, whereas the Nam Con Son Basin experienced a younger phase of extension during late Miocene time.  Viable petroleum systems are known to exist in both basins, as substantiated by recent petroleum discoveries in both basins.  Regional 2-D seismic reflection data that cover the southern and southeastern continental margin of Vietnam and information from twenty petroleum industry wells contributed to this study. Structural features, seismic facies, and seismic stratigraphic patterns have been mapped within the early Pliocene to Recent succession.  The available data provide a unique opportunity to map sediment dispersal systems, from up-dip fluvial environments to down-dip deep-water slope and basinal environments that operated along the southern continental margin of Vietnam during late Miocene to Recent time. There are few data sets from anywhere on Earth where mapping similar depositional patterns at such large temporal and spatial scales is possible. The stratigraphic framework that is being constructed in this study will also be related to eustatic sea-level change, differential subsidence across the study area, and sediment flux from various continental source areas in Asia.