Analysis Of Sequence Filling Characteristics Of Paleogene Dongying Formation In Liaoxi Sag, Liaodongwan Area

According to dozens of drilling core's sedimentary structure marks, electrofacies marks and fossil marks, it can identify several depositional systems in Liaoxi sag area of Liaodongwan Basin, Based on geophysical data(logging and seismic interpretation) and palaeontology identification,observation of the core,including braided-river delta, meandering-river delta, fan dalta, lacustrine and turbidite fan.The paper have analyzed in detail the sedimentary facies, parfacies and microfacies.On the basis of identification and tracking of fine sequence boundaries.Combining with three-dimensional seismic date, based on the theory of sequence stratigraphy, the Dongying foration of Paleogene was divided into three third-order sequences and established the isochronal stratigraphic frame.On the basis of Identification and tracking of fine sequence boundaries, and get the sequence characteristics of the study area, then compared with the wells in the linked-well section.Based on the comprehensive consideration of the difference of sequence filling between the Dongying formation of the Paleogene System, we selected four representative sections from the south to the North to discuss the controlling factors of the characteristics of sequence filling structure.The results show that: The sequence development of the Liaoxi Sag is mainly influenced by tectonic movement, source supply, raising and falling of lake watertable and the palaeogeomorphology, and the strong tectonic movement and source supply are dominant factors.