THE OIL-GAS EXPLORATION POTENTIAL OF CHINDWIN SAG IN THE CENTRAL BASIN IN BURMA

On the basis of analyzing regional structure and evolution characteristics, It is considered that undergoing 3 evolutions of Eocene-Oligocene, Miocene and Pliocene exploration, Burma central basin Formed in Tertiary and can be divided into 2 secondary grade structural units, i.e. western deep depression and eastern shallow depression, and 11 third grade structural units, such as Irrawaddy sag, Prome sag, Salin sag, Chindwin sag, Hukawng sag, Putao sag, Shwebo sag, Inlelake sag, Salween sag, Sittang sag and Pegu upwarping. The detritus transported into sea from north to south to form the longitudinal progradation delta and its Cenozoic thickness is more than 20000 m. The outcrop and drilled data indicate: the source rocks of Chindwin sag mainly are the shales of Yaw Formation, Laungshe Formation and Kabaw Formation; the reservoirs are Cretaceous-Eocene sandstone and the cap rocks are mud shales with great thickness and extensive distribution. Chindwin sag is of upper, middle and lower 3 sets of favorable source-reservoir-cap assemblage and its peak period of hydrocarbon-generating is the late stage of Miocene. The oil and gas formed from Yaw Formation, Laungshe Formation and Kabaw Formation migrated up along the slope. With a large scale, the INDAW structure and YENAN structure have favorable preservation conditions and abundant recoverable resources. So, it is possible to find large-medium oil and gas fields in Chindwin sag.