Mineral system modeling of Lithium-Cesium-Tantalum (LCT)-type pegmatites: Regional-scale exploration targeting and uncertainty analysis in the Sanandaj-Sirjan zone, Western Iran

Abstract

Granitic pegmatites, particularly lithium‑cesium‑tantalum (LCT) types, are vital sources of rare metals crucial for modern technologies, including sustainability, energy storage, and green energy applications. Exploring and targeting LCT pegmatites are essential to meet the increasing demand for critical metals like lithium in green technologies. Mineral prospectivity modeling provides a systematic approach to identifying these deposits, especially in regions such as western Iran, where the Sanandaj-Sirjan Zone (SaSZ) is the potential host of LCT pegmatites. This study aims to model the prospectivity of LCT pegmatites in the SaSZ, with three primary objectives: (i) to construct a mineral systems framework that defines the critical processes controlling the genesis of LCT pegmatites and their mappable proxies, (ii) to identify high-priority exploration targets using knowledge-driven approaches, and (iii) address uncertainties stemming from limited data availability (epistemic) and from the integration of multiple models (systemic) to improve exploration reliability. To achieve these objectives, three well-known knowledge-based algorithms—fuzzy inference systems, continuous fuzzy gamma, and geometric average—were employed using publicly available geo-exploration datasets to generate prospectivity models based on the mineral systems approach. These were subsequently combined into a final predictive model using a majority voting (MV) ensemble technique. A confidence index (CI) was incorporated to quantify and mitigate uncertainties associated with the multi-algorithm approaches, delineating low-risk, high-confidence zones for future exploration. The results show high prospectivity zones (~2 % of the study area) in the northern and southern parts of the SaSZ, particularly near the Alvand complexes, predominantly located farther from their host plutons and within metamorphic aureoles. This study highlights the efficacy of integrating mineral systems frameworks with geospatial modeling to optimize exploration strategies. Future research should prioritize acquiring high-resolution geophysical and geochemical data and conducting systematic ground-truthing to validate and refine these targets, ensuring economic feasibility and resource-efficient exploration.