Mapping Gravity Flow Depositional Systems using Seismic Sedimentology

Key words: 
• rifted lake basin /
• seismic sedimentology /
• gravity flow channel /
• stratal slices /
• the first member of Shahejie Formation (Es₁) /
• Qikou sag

Abstract: This paper discusses the research idea of mapping gravity flow depositional systems based on seismic sedimentology method. Case study on the thick layer sandstone of the first member of Shahejie Formation in Qinan slope, according to the theory and method of seismic sedimentology, this paper puts forward a program of seismic sedimentology suitable for China's continental fault basins with gravity flow depositional systems:first, the high frequency sequence stratigraphic framework are performed through time-frequency analysis and frequency decomposing technology; then application of seismic geomorphology and macroscopic attribute constraint source direction; Combining with core calibration to determine sedimentary facies types; and lastly, stratal slicing, seismic inversion and 3D visualization showing the spatial and temporal distribution of the gravity flow channel, application of this method and techniques to seismic sedimentology study, gravity flow channel sand body is clearly characterized. This study provides favorable exploration areas for finding hydrocarbon reservoirs in lacustrine mudstones in Qikou sag, good results have been produced and enriched fundamental research of seismic sedimentology.