## 3 Data and Methods  
At present, there are three main criteria for sequence division in sequence stratigraphy. The first one is the classic type, presented by [22]. It is marked by the unconformity surface formed by the beginning and end of the sea level drop or its equivalent integration surface, emphasizing that the cause of the sequence unconformity interface is controlled by the rapid sea level drop. According to the degree of exposure of the shelf-slope break caused by the sea level drop amplitude and rate, the sequence interface is divided into two types: type I and type II sequence interfaces. The second one is the genetic stratigraphic sequence type, presented by [23]. It is marked by the maximum flooding surface as the interface between the top and bottom of the sequence. This scheme fully emphasizes the instantaneous isochronism of the interface between the top and bottom of the sequence, while ignoring the division and correlation of other sedimentary bodies and even unconformities within the sequence. Third, the base-level cycle type is represented by [24]. It is considered that the stratigraphic base-level cycle is key to controlling the formation and division of stratigraphic sequences. The stratum datum level is restricted by sea level change, tectonic subsidence, sediment compensation, material supply rate, and sedimentary topography. This study used geophysical well logs, drill cores, and seismic sections from seven selected wells (wells A, B, C, D, E, F, and G) in the ST gas field. The seismic data cover an area of \(\sim\)1333 km\({}^{2}\). These data, along with the existing knowledge of Jurassic stratigraphic framework in the study area, theories of both classic and high-resolution sequence stratigraphy, fine stratigraphic division, and correlation technology, are all used to identify sequence boundary and flood surface; divide the third-, fourth-, and fifth-order sequences of a single well; delineate core and logging characteristics of each sequence; establish the well-seismic third- and fourth-order stratigraphic correlation framework; and define the evolution characteristics of \"TST-HST\" sequence of Jurassic strata. Compared with shallower reservoirs, the reservoir quality in the deeper Jurassic strata is poorer and the lateral change is fast. Lithologic reservoirs with strong heterogeneity and thin interbeds are gradually becoming the main targets to replace reserves, and the difficulty of hydrocarbon exploration and development is increasing; especially the comprehensive popularization of horizontal wells puts forward higher requirements for fine reservoir prediction. The traditional inversion method is channel-by-channel, mainly considering the vertical variation of seismic amplitude (one-dimensional), but not the lateral variation of seismic waveform (three-dimensional). Moreover, it is a non-phased simulation algorithm with poor cross-well prediction. On the other hand, seismic waveform represents the tuning pattern of the vertical lithology combination of the reservoir, and its lateral change reflects the phase change characteristics of reservoir space, which is related to the sedimentary environment. Therefore, this study plans to adopt the method of \"structural statistical representation driven by seismic waveform\", and use the lateral change of waveform to represent the variability of reservoir spatial structure, which is more in line with the sedimentary geological law (Figure 2).