Seismic sedimentology is a subject using seismic information and technology to study sedimentary rocks and their formation process.It is a new edge inter-discipline after seismic stratigraphy and sequence stratigraphy.After ten years' development, unified understandings about the theoretical basis, research ideas and content of seismic sedimentology are formed currently in China, but the key technologies for realization are still being explored. In this thesis, aimed at the study methods and technical limitations of traditional seismic sedimentology, new concepts of the seismic sedimentology are proposed.The geophysical technologies are used to fully tap the effective geological information carried by seismic data and to achieve a completed study on the depositional process of sedimentary systems, from macro-depositional sequence division to reservoir fine description of micro-sand formation.According to this concept, Dongying Delta in Jiyang Depression is selected as the main target study area, through the combined analysis of seismic with geology, namely seismic well-tie framework profile, structure seismic facies, sequence boundary and inner structure, wheeler forward / inverse transform, reservoir fine prediction constrained by stratigraphic sequence as well as depositional history, a series of new technologies including depositional phase division, establishment of 3D stratigraphic isochronous framework, inner structure analysis of unit sedimentary body, sedimentary body prediction based on genesis model are established.Based on the depositional phase division, the seismic time-frequency analysis technology is developed based on high-order statistics, through which, Dongying Delta is divided into 9 phases using the analysis method of plus time window third-order amplitude spectrum; based on the establishment of stratigraphic framework, using seismic wheeler domain transform technology, the 3D isochronous delta stratigraphic framework of each phase is built up according to the isochronous tracking of spatial sequence boundary and delta phase boundary constrained by dip angle.On this basis, the internal stratigraphic structures of each delta phase are characterized through the development of seismic facies analysis method based on structure; according to the development of backstripping forward and shore line trajectory method, the paleo-geomorphology and paleo-water-depth of this area are recovered and the delta genesis model based on paleo-geomorphology and paleo-hydrodynamic conditions are established, in the model, the detailed structure features including sand-mud ratio, geometry, sedimentary slope and planner distance are clarified, combined with multiple-attribute seismic analysis and wave impedance inversion technology, the prediction of depositional systems spatial distribution is completed. Through the comprehensive seismic and geological study, a set of seismic sedimentology study technologies and methods aimed at Jiyang Depression Dongying Delta are formed, according to which the favorable turbidite development area are predicted and the exploration potential evaluation of the non-structural traps of corresponding area are proposed.
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