Pegmatite Cluster Aggregation Patterns and Tectonic-Magmatic Coupling Ore-Controlling Mechanisms in the Ke'eryin Lithium Ore Field, Sichuan Province

Objective The Ke'eryin pegmatite field in Sichuan Province, a critical lithium ore concentration area in China, has been designated as a key target zone in the new round of prospecting breakthrough strategy. However, insufficient studies on ore-controlling factors, particularly the mechanisms governing the distribution and morphological characteristics of pegmatite veins and lithium orebodies, have hindered regional target prediction and exploration. Methods This study systematically investigates the spatial distribution patterns of pegmatites in the Ke'eryin area, statistically analyzes their attitudes, and evaluates their relationships with the Ke'eryin pluton and regional structures to decipher the structural controls on lithium mineralization. Results The spatial distribution, morphology, and scale of pegmatites exhibit intrinsic correlations with the pluton, regional structures, and joint-fracture systems. A tectonic-magmatic coupling mechanism is proposed, identifying anticlinal cores and adjacent regions at specific distances from the Ke'eryin pluton as favorable structural loci for mineralization. Three pegmatite cluster patterns are established based on morphological and spatial aggregation characteristics: parallel, en echelon, and network types. The distribution, scale, and geometry of pegmatites and lithium orebodies are dominantly controlled by two-phase structural fracture systems: longitudinal tension joints associated with NW- and E-W-trending folds, and sub-circular/radial joints formed by magmatic doming of the Ke'eryin pluton. Conclusion The tectonic-magmatic coupling model effectively delineates mineralization-favorable zones, while pegmatite cluster patterns provide critical guidance for lithium exploration. This approach has led to the discovery of one large and one medium-sized lithium deposit in the Ke'eryin area, with nine prospective targets further proposed. The findings offer significant theoretical foundations and exploration strategies for regional lithium resource assessment.