Geology, petrography and geochemistry of igneous rocks related to Chaloo Fe skarn, south of Damghan, Semnan province


Faculty of Earth Sciences, Damghan University, Damghan, Iran


Chaloo skarn deposit is located in the south of Damghan. Massive limestone with andesite and andesitic dacite volcanic rocks are wall rocks of mineralization. Diorite intrusive rocks are related to Fe mineralization in Chaloo skarn deposit. Geochemically, intrusion rocks in this deposit is calc alkaline and display I type granitoid metalminous related to volcanic arcs. Negative anomalies of HFS elements like Nb, Ti, Ta and P and positive anomalies of K and Pb show a volcanic continent arc related to subduction. SiO2 content of intrusive rocks in Chaloo deposit coincides with intrusive rocks related to Fe skarn mineralization. But major oxide content of Al2O3, TiO2, MgO, P2O5 of this diorite intrusions coincides with average content of intrusion compositions related to worldwide Cu and Fe skarn mineralizations. The ratios of Rb/Nb, Rb/Ba and Zr/TiO2 of intrusion body of Chaloo skarn are similar to intrusion compositions of Cu skarns. The ratio of Ga/Al if Chaloo skarn is similar to intrusion body is related to Fe skarn deposit. Comparison of average compositions of intrusion body of Chaloo deposit with average content of intrusive rocks related to Cu and Fe skarn systems suggests new exploration possibilities for copper in Chaloo deposit.


اشراقی، س.، الف.، جلیلی، الف.، 1385، نقشه زمین شناسی 100000/1 معلمان، انتشارات سازمان زمین شناسی کشور
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