Systematic exploration and identification of promising mineralized zones in the Karaj-Damavand zone: by processing, compilation, and modeling geological, geophysical, geochemical, remote sensing and mineral data with GIS
In order to perform the Third Development Program of Country, the Geomatics department of GSI started a systematic exploration project for 20-defined zones across Iran. The Karaj-Damavand zone is one these defined zones that is located in the Central Alborz and includes four 1:100000 sheets (Karaj, Tehran, Fasham and Damavand). This zone is number 18 of 20 defined zones. It is located between 50 30' to 52 30' E and 35 30' to 36 30' N.
For identification of metallogenic phenomena we should focus on three factors of the Intrinsic Geologic Unit (source rock), Critical Genetic Factors (host rock, structure …) and Critical Recognition Criteria (alteration, geochemical and geophysical anomalies and mineralization evidence).
The study was done through determination of genetic model (epithermal gold mineralization for this zone), determination of genetic parameters (structure, thermal source, geology and mineralization process) and identification of genetic parameters using the geological, geophysical, geochemical, remote sensing and mineral data. Then the genetic parameters will be prioritized based on their importance in the genetic model. Modeling and identification of promising zones is done by GIS methods. The identified promising areas are controlled in the filed and then introduced or omitted for further studies.
The result of study shows that two methods of Index Overlay and Weight of Evidence are applicable for identification of promising areas; however the filed checking step cited that the Index Overlay method has more reliable result. Heavy mineral studies also confirmed the correctness of compilation procedure. The report includes the map of promising mineralized area that can be studied in the future.