In the local geological context, the study area represents the southern segment of the Kohistan Batholith (KB), adjacent to the Chilas Complex. In this region, the KB is composed entirely of granite, syenite, and pegmatite, which represent stage 3 intrusions that were emplaced into pre-existing gabbroic rocks. The syenite contains irregularly shaped patches and dikes of pegmatite enriched in REE–bearing minerals, including chevkinite (5–15 vol%), monazite (10–20 vol%), and apatite. In contrast, the pegmatite associated with the syenite in this study is peralkaline, reflecting a distinct source and tectonic control during emplacement. The mineralization style also differs significantly: LCT-type pegmatites are typically zoned, associated with Li-Be mineralization, genetically linked to post-collisional S-type granites, and lack REE enrichment. In the upper reaches of the Tangir and Darel valleys, the syenite hosts alkaline pegmatites ranging in thickness from approximately one meter to several meters. These pegmatites exhibit no typical internal zoning and are highly enriched in REEs. The alkaline nature of both the syenite and its associated pegmatites distinguishes them from the highly peraluminous LCT-type pegmatite fields distributed along the MMT suture zone. This contrast highlights a fundamental difference in petrogenesis, reflecting distinct tectonomagmatic regimes operating along the MMT during the post-collisional evolution of the KIA.

Other Regions, Features and Areas containing this locality

References