RESERVOIR DISTRIBUTION IN DEEPWATER AREA OF THE QIONGDONGNAN BASIN

The Qiongdongnan Basin has undergone 3 stages of tectonic-sedimentary evolution,i.e.rift-ing,fault-depressing and depressing.There are 4 sedimentary systems which respectively develop 4 major types of reservoirs:a) the fan deltaic or littoral sandstone of Ling-III Member;b) the littoral facies sandstone of Sanya-Meishan Formations;c) the sandstone of lowstand system tract of Sanya-Yinghuang Formations;and d) the Miocene platform limestone of Meishan Formation.Spatially the reservoirs develop in 3 different zones,i.e.the northern shallow shelf zone developing deltaic and littoral facies sandstones,the central depression zone developing LST sand bodies,and the southern Yongle Uplift zone developing carbonate rocks.The deepwater area mainly covers the latter 2 zones.Due to the difference of controlling factors,each reservoir zone can be further divided into several areas,and each area may develop several reservoir-seal combinations.The Miocene platform limestone may be an important exploration reservoir in the southern Yongle Uplift.