# Weight Assignment Method and Application of Key Parameters in Shale Gas Resource Evaluation
## 2 Resource Evaluation Methods and Parameters
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Shale Gas Resource Evaluation Method** & **Basic Evaluation Method** \\ \hline \multirow{4}{*}{Static method} & \multirow{2}{*}{Statistical method} & \multicolumn{1}{c}{Geochemical method} \\  & & Basin simulation method \\ \cline{3-3}  & & \multicolumn{1}{c}{Volumetric method} \\  & & \multicolumn{1}{c}{Forspan model method} \\  & & \multicolumn{1}{c}{Random simulation method} \\  & & \multicolumn{1}{c}{Trend analysis method} \\ \cline{3-3}  & & \multicolumn{1}{c}{Resource Abundance Analogy} \\  & & \multicolumn{1}{c}{EUR Analogy} \\  & & \multicolumn{1}{c}{Gas content analogy method} \\ \hline \multirow{4}{*}{Dynamic method} & \multicolumn{1}{c}{Material balance method} \\  & & \multicolumn{1}{c}{Decline curve method} \\ \cline{3-3}  & & \multicolumn{1}{c}{Numerical simulation method} \\ \cline{1-1} \cline{2-3}  & & \multicolumn{1}{c}{Delphi method} \\ \cline{1-1} \cline{2-3}  & & \multicolumn{1}{c}{Expert system method} \\ \hline \hline \end{tabular}
\end{table} 
Table 2: List of resource evaluation methods. There are significant differences between conventional and unconventional oil and gas in terms of distribution characteristics, source reservoir combinations, migration modes, accumulation mechanisms, and seepage characteristics [21]. Similarly, in the process of resource evaluation, different evaluation methods will be selected based on the exploration degree and geological understanding of the basin/region to be evaluated [22; 23; 24; 25]. There are various methods for resource evaluation, and existing research on key parameters generally corresponds to resource evaluation methods, mainly focusing on the selection of specific parameters for a certain method and the selection of parameters based on actual production conditions. There is relatively little research on the analysis of parameters themselves [26]. In resource evaluation, key parameters refer to the direct parameters of quantitative analysis that directly affect the accuracy of resource estimation. Different resource evaluation methods involve different direct parameters, such as genetic methods, which mainly involve geochemical parameters such as the hydrocarbon generation potential index, TOC, total hydrocarbon content, and hydrocarbon production rate. The analogy rule focuses on standard zone parameters and analogy coefficients. The statistical method parameters involve geological parameters such as area and thickness. The comprehensive rules reflect various resource calculation results and weight analogies (Table 4). When conducting resource evaluation, key parameters can be divided into two categories: direct parameters that directly participate in the calculation and indirect parameters that do not directly participate in the calculation. The accuracy of common parameters that participate in direct calculation will affect the accuracy of resource evaluation. There are many existing resource evaluation methods, but the key parameters are relatively consistent, generally considering the shale thickness, area, density, etc. Due to the varying degrees and ranges of parameter values of these key parameters with geological conditions such as sedimentary structures, if the importance of all parameters is considered unified, this will result in significant errors. Therefore, in resource evaluation, it is crucial to conduct a weight analysis of the key parameters in the selected methods. By determining the importance of different parameters, the actual geological conditions of the target block can