## 5 Conclusions  
1. A technical workflow for the characterization of shallow-water fan-delta reservoir architecture is developed in this study. Guided by the main points of seismic sedimentology, the characterization of fan-delta complexes and single-stage fan-delta single lobes are realized. Mixed-phase wavelet frequency broadening is employed to increase the quality of seismic data; thus, the ability to identify the thin layer of about 10 m is enhanced; for the characterization of the fan-delta complex, which is about 50 m, the RMS amplitude attribute is employed; for the characterization of the single-stage fan delta, which is about 25 meters, INPEFA is employed to identify the numbers of stages and the continuous stratal slice is employed to describe the plane  
Figure 13: Near-source (**a**) and far-source (**b**) well sections (position of the section line is shown in Figure 10e,f). development of the single-stage fan delta; for the characterization of single lobes, the color fusion of frequency decomposition data is employed to offer an improved characterization of the fan boundary and show the plane development with thickness information; the inner structure of a single lobe is revealed by two typical well profiles of near source and far source. In summary, the fine anatomy of the shallow fan-delta complex is realized. 2. A shallow-water fan delta has been identified in the study area. This delta is characterized by coarse clastic deposits, such as glutenite and gravel-bearing coarse sandstone. At the base of the fan body, there is the development of mudflow. Within the delta plain, three types of microfacies were observed, namely mudflow, braided channels, and flood plains. The delta front exhibits the presence of an underwater main channel, underwater distributary channels, an estuary bar, sheet sand, overbank channel deposits, and interchannel deposits. Notably, the estuary bar of the shallow-water fan delta is found to be laterally associated with the underwater distributary channel. In contrast to the typical fan delta, the estuary bar in this case is widely developed and shows lateral connectivity with the distributary channel sand body. Furthermore, the presence of interlaced continuous sheet sand bodies within the channels and estuary bars is also observed. 3. In the study area, two extensive fan-delta complexes were formed in the S3 sand group, specifically in the S31 and S32 sublayers, both of which exhibit inherited characteristics. Within each sublayer, two large individual fans were developed, contributing to the formation of the shallow-water fan-delta complex. One of these individual fans is located in the northern part of the study area and extends toward the southeast, while the other is situated between the central and southern parts. The central and southern individual fan further developed into two lobes. Throughout the S31 period, the fan-delta complex experienced expansion. Although the size of the northern fan remained consistent, it gradually migrated toward the south. 4. Deposition in areas near the source is primarily influenced by the distribution of rivers on the fan delta. Two vertical stacking patterns of sand bodies in S32 were observed: one is characterized by an upward transition from estuary bars to channels, and the other exhibits a vertical transition from channels to estuary bars. These stacking patterns indicate different water level evolution. In S31, the sandstone is thick and shows limited development of interlayers. The sandstone formed later and eroded the structures that were formed earlier. 5. Deposition in areas far away from the source is primarily dominated by underwater distributary channels and sheet sand in the shallow-water fan-delta front. Although the presence of estuary bars can be observed, they do not constitute the dominant types of sand bodies. Furthermore, the mudstone interlayers in this region are more pronounced compared to those in the near-source area. Laterally, sand bodies overlap, and their connectivity on the plane is good.