Study on Basin-Filling and Reservoir Sedimentology of Zhu Ⅲ Depression of Pearl River Mouth Basin, South China Sea

摘要

Through basin-filling analysis, one coarsening-upward and two fining-upward sequences have been identified in Zhu Ⅲ depression. In accondance with the general model proposed by Ravnas and Steel (1998), the basin-filling has two large cycles-rift (sediment-balanced and -overfilled) and postrift (sediment-underfilled and -starved). During the rifting process, the rifted lake devel- oped through three stages: early, climax and late. The sedimentary characteristics of reservoir rocks show that barrier bar, lagoon and tidal channel facies well developed in Zhuhai Formation; offshore, tidal and barrier bar well developed in Zhujiang Formation. Neighborly, Shenhu, Wen- chang and Enping formations deposited in rifted lackes during Paleogen time; Zhujiang Formation deposited in bay, lagoon and shoreface in late Paleogene. Zhujiang and other formations deposited in offshore and open shallow sea to shelf.