## 6 Discussion  
### Tectonic Setting  
The R1-R2 tectonic setting discrimination diagram developed by [24] and the tectonic setting fields based on [31] can be used to classify different types of granitoids based on their geochemical signatures and relate them to specific tectonic environments (Figure 11a): (1) Subduction-related granitoids that are represented by the granodiorite-diorite association. These granitoids are typically related to an early stage in the orogenic cycle, characterized by subduction or pre-plate collision magmatism; (2) collision-related granitoids that are represented by monzogranites. The presence of monzogranites in the studied granitoids indicates a transitional stage in the orogenic cycle, where the tectonic collision has occurred, leading to the generation of collision-related magmas; (3) post-orogenic/Anrogenic granitoids that are represented by peralkaline granites. The presence of these rocks suggests a late stage in the orogenic cycle, characterized by post-orogenic or anorogenic magmatism. These observations support the idea that the granitoids in the Jabal Sayid and Dayheen areas may represent different stages within a single orogenic cycle, reflecting the evolving tectonic processes that occurred during their formation (blue dashed lines with arrows in Figure 11a).  
Figure 11: (**a**) The R1-R2 tectonic setting discrimination diagram of [24], with tectonic setting fields based on [31]. The blue dashed line with arrows reflects different stages within a single orogenic cycle. (**b**) Y + Nb vs. Rb discrimination diagram [29], post-collisional field (red dashed circle) after [PERSON] (1996). VAG = volcanic arc granite, SYN-COLG = syn-collision granite, ORG = ocean ridge granite, and WPG = within-plate granite. Symbols as in Figure 6.  
In the Y + Nb vs. Rb discrimination diagram ([29]; Figure 11b), the Jabal Sayid and Dayheen peralkaline granite samples fall within the within-plate field. This indicates that these samples have geochemical characteristics consistent with an intraplate tectonic setting. In contrast, the Dayheen granodiorite-diorite samples fall within the volcanic-arc granite field. This suggests that these samples have geochemical characteristics similar to those of subduction-related granitoids. Furthermore, the Dayheen monzogranite samples fall within the post-collisional field as defined [32]. This indicates that these samples have geochemical characteristics consistent with collision-related granitoids.  
The chemical characteristics described for the Jabal Sayid and Dayheen peralkaline granites suggest a within-plate tectonic setting. These characteristics include significant depletions in CaO, MgO, Sr, and transition metals, along with high alkali contents and notable enrichments in High-Field-Strength Elements (HFSEs) such as Zr, Nb, Ta, and rare earth elements (REEs). The pronounced negative Eu anomalies in the REE patterns of the granites (Figure 9a,b) indicate the involvement of plagioclase feldspar fractionation in their petrogenesis, where the preferential removal of Eu\({}^{2+}\) from the melt leads to the relative depletion of Eu compared to the other REEs. Overall, the described geochemical features are consistent with the within-plate tectonic setting of the Jabal Sayid and Dayheen peralkaline granites, indicating their formation in an intraplate environment away from plate boundaries [33; 34; 35].