# A New Method of Geological Modeling for the Hydrocarbon Secondary Migration Research
## 6 Conclusions  
Understanding the architecture of a reservoir is essential for predicting fluid flow behavior and optimizing the development of oil and gas resources. It is essential for the sustainable oil and gas exploration and recovery, especially in deep and ultra-deep underground zones. In this study, we proposed the following three reservoir architecture characterizations: point bar, braided channel, and river mouth bar. Each of these characterizations captures lower-scale heterogeneity, drawing upon sedimentary processes and evolution laws. These reservoir architecture characterizations act as prototypes for the object-based modeling method that is the focal point of this research. A point bar unit element is composed of inclined alternating packages of lateral accretion sand bodies, mud drapes, and abandonment channel fills. The multi-stage lateral accretion bodies exhibit a diverse planform morphology, categorized into 25 shapes and 4 parent groups, separated by stochastically distributed mud drapes. For the braided unit element, it corresponds to a braided river belt defined by a fifth-order boundary. In order to establish a standardized nomenclature for architecture elements within braided channels, a comparative analysis was conducted, leading to the proposal of a new braided architectural unit. This new unit integrates the key elements necessary for constructing braided reservoirs. The braided unit element exhibits a lenticular cross-section, resembling the geomorphology of river depressions, and an elliptical or lobate planform, representing the inconsistent preservation of river channels. Within this braided unit element, intra-channel deposits include individual 'unit bars', individual channel fills, and interpeds comprising fall-siltseams and upper-floodplain fine-grained sediments. The unit element has a flat bottom and a convex top, superimposing within a convex downward lenticular braided channel sand. Fall-siltseams are extended to cover the perimeter of unit bars. On the other hand, a mouth bar unit element exhibits a dipping longitudinal section and a lenticular cross-section. The base deposits of this unit consist of fine-very fine grains, characterized by poor plastic lithic grains or calcareous cementation. The bodies of these architecture units act as \"objects\" to be filled and fitted into the geological model using stochastic modeling methods under the control of well and seismic data. Internal architecture elements such as mud drapes of meander bends, unit bars deposited in braided channels, and calcareous cementation at the base of mouth bars are randomly generated, controlled by the geometry and size of the unit elements. Physical properties can be assigned to all of the architecture elements, indicating the path or barrier of the fluid flow. A modeling case was explained in detail, aiming to construct a braided environment reservoir and evaluate the target area using this novel object modeling method. The reliability of the reservoir modeling results was tested by comparing the drilled sand thickness with the modeled sand thickness. The overall agreement rate was 92.4%, indicating the credibility of the reservoir modeling results. To illustrate the effectiveness of this novel object-modelling method, a detailed modelling case was presented, focusing on constructing a reservoir in a braided environment and evaluating the target area. The reliability of the reservoir modelling results was assessed by comparing the drilled sand thickness with the modeled sand thickness, yielding an overall agreement rate of 92.4%. This high agreement rate demonstrates the credibility of the reservoir modelling outcomes. In short, the main conclusions from the works can be summarized as follows:  
* The method uses specific reservoir architecture characterizations (point bar, braided channel, and river mouth bar) as \"unit elements\", built upon sedimentary processes and evolution, to represent the reservoir heterogeneity.