Preparation of 1:50,000-scale geochemical exploration and heavy mineral maps

Principal Investigator: Dr. Afshin Akbarpour

Project Period: 2024–2026 (1403–1405)

Six 1:50,000-scale geochemical exploration and heavy mineral map sheets in South Khorasan Province (Darreh, Parang, Khoshab, Dastgerd, Zeydan, and Ardoul) were initiated in 2024 (1403) and completed in 2026 (1405). In 2025 (1404), four additional map sheets in the Naein Zone (Mishab, Zefreh, Soheil, and Kahyaz) were launched and are currently in the report preparation stage.

In 1:50,000-scale geological map sheets, geochemical exploration and heavy mineral studies play a key role in identifying prospective areas for mineral deposits. These map sheets provide detailed baseline information for the interpretation of exploration data.

Heavy mineral investigations in stream sediments represent one of the most cost-effective regional exploration methods, allowing rapid coverage of large areas. Heavy minerals with densities greater than 4.5 g/cm³, such as zircon, rutile, cassiterite, and magnetite, naturally accumulate in stream sediments and serve as important indicators of upstream mineralization. For specific indicator minerals, such as scheelite (a tungsten-bearing mineral), geochemical analysis can provide an accurate guide toward potential mineral sources. This approach has also been successfully applied in the exploration of a wide range of mineral resources, including gold, copper, diamonds, and rare earth elements.

The application of stream-sediment geochemistry at the 1:50,000 scale involves sampling the −80 mesh fraction of stream sediments followed by multi-element geochemical analysis, providing valuable information for subsurface geological interpretation. In many areas where bedrock exposure is limited, this technique represents the most effective approach for regional exploration mapping. Integrating heavy mineral data with geochemical analytical results provides a powerful model for identifying geochemical anomalies and prioritizing target areas for more detailed exploration.