## 5 Results and Discussion
### Statistical Analysis Results
#### 5.4.3 Cluster Analysis  
Applying HCA on the studied samples showed two clusters reflecting two types of source rocks (Figure 7). Cluster II was source rock that included the samples from well (b-65-J/94-B-16), Cluster I was the source rock that contained the rest of the samples. The results of this clustering technique were not consistent with the results of the geochemical analysis shown in (Figure 5B).  
\begin{table}
\begin{tabular}{c c c c} \hline \hline  & \multicolumn{2}{c}{**Rotated Component Matrix 1**} \\ \hline  & Factor 1 & Factor 2 & Factor 3 \\ \hline S\({}_{2}\) & 0.902 & & \\ TOC & 0.873 & & \\ S\({}_{1}\) & 0.733 & & \\ OI & \(-\)0.666 & & \\ PI & & 0.853 & \\ S\({}_{3}\) & & 0.689 & \\ Tmax & & & \(-\)0.795 \\ HI & & & 0.790 \\ \hline \hline \end{tabular} Extraction Method: Principal Component Analysis. Rotation Method: Varimax with Kaiser Normalization.  
\({}^{\rm a}\) Rotation converged in 6 iterations.  
\end{table}
Table 3: PCA of the pyrolysis parameters for the studied samples of Montney Formation showing the extraction of three components.  
Figure 6: Graphical modeling of Spearman correlation coefficient for the studied samples of Montney Formation.  
Applying the TwoStep cluster analysis on the pyrolysis results of the studied samples showed two clusters with a fair Silhouette measure of cohesion and separation (Figure 8). The two clusters reflected two different levels of maturity and generating potentials as the samples were related to the same source rock. The first cluster was characterized by TOC > 1.41 wt.%, S1 > 0.71 (mg HC/g rock), S2 > 0.48 (mg HC/g rock), S3 > 0.41 (mg CO2/g TOC), Tmax < 455 \({}^{\circ}\)C, HI > 39.5 mg HC/g TOC, and moderate OI (Figure 9), while the second cluster was characterized by TOC < 1.41 wt.%, S1 < 0.71 (mg HC/g rock), S2 < 0.48 (mg HC/g rock), S3 < 0.41 (mg CO2/g TOC), Tmax > 455 \({}^{\circ}\)C, HI > 39.5 mg HC/g TOC, and moderate OI (Figure 9); these results were consistent with the geochemical results shown in (Figure 5B).  
The results of the TwoStep clustering method divided the samples into two main clusters. The first lay in the oil window zone with relatively high TOC, S1, S2, S3, HI, PI, and GP accompanied by low Tmax and neutral OI (Figure 9). The second cluster was in the dry gas window with relatively low TOC, S1, S2, S3, HI, PI, and GP accompanied by high Tmax and neutral OI (Figure 8).  
The results indicated the efficiency of using this tool in distinguishing between the samples based on generating potential and maturity. Moreover, the clustering technique showed the predictor importance of the different parameters (Figure 10) where the HI forms the significant parameter in evaluating the source rocks followed by moderate to high effect for the S1 and S2 with low impact for the TOC and Tmax and neutral influence for the OI (Figure 9).  
Figure 7: Dendrogram based on hierarchical cluster analysis and average linkage (between groups).  
Figure 8: The TwoStep clustering model details the main five pyrolysis components showing the number and quality of clusters.  
Figure 9: The two clusters resulting from the application of the TwoStep clustering technique.