Pegmatite and Fault Spatial Distribution Patterns in Kalba-Narym Zone, East Kazakhstan: Integrated Field Observation, GIS, and Remote Sensing Analysis

This study is an attempt to compile and complete structural features of the Kalba-Narym Zone in East Kazakhstan belonging to the western Central Asian Orogenic Belt, which is known to be well-endowed with the occurrence of pegmatite rare-metal mineralization. Remote sensing and GIS-based 2D are utilized to map the geological structural lineaments of faults and granitic pegmatite and pegmatite dikes. This includes lineament extraction on regional and district scales. Then, the spatial relationship between pegmatite dikes and faults is analyzed, including the lineament trends and proximity patterns. The spatial analyses are performed via the geo-computational method of Distance to Nearest Neighbors (DNN), Ripley’s L′ function, and pegmatite orientation families were employed to study the spatial distribution pattern of the pegmatites. The results of this study demonstrate that the occurrence of pegmatite dikes in various Greenfields and Brownfields of the Kalba-Narym Zone follows clustered distributions, the orientation of pegmatite swarms is dominantly NW-SE, and pegmatite emplacement is proximal to the intersection of multiple faulting systems. Extracted fault strikes, demonstrating a pronounced NW–SE to NNW–SSE structural fabric across the zone, show orientation association with the pegmatite dikes. Extraction and demarcation of pegmatites on a regional scale via remote sensing techniques help efficiently narrow down the target areas before conducting geological campaigns. This investigation proposes several new districts of pegmatite occurrence in the Kalba-Narym Zone as potential targets for exploration of critical metals.