Document Type : Original Research Paper
Authors
- Keytash Moshtaghian 1
- Seyed Mohammad Abtahi Forooshani 1
- Hooshang Asadi Harooni 1
- Mohammad Hajheidari 2
- Ghazal Janghorban 1
1 Department of Exploration, Faculty of Mining Engineering, Isfahan University of Technology, Isfahan, Iran
2 Mining Exploration Engineering/Department of Mining Engineering/Isfahan University of Technology/Isfahan/Iran
Abstract
The Dalli porphyry Copper-Gold deposit consists of two northern and southern indexes located on the Urmia-Dokhtar Volcanic Belt in Markazi province. Due to the presence of magnetite beneath the potassic alteration zone in the center of porphyry mineralization, a magnetometric survey was performed in the region. In the current study in the northern index, first, we extracted the local anomaly via removing the regional and aliasing effects from the magnetic data. Then, using three-dimensional inverse modeling of the reducted data illustrates the presence of a body with high magnetic susceptibility, in the depth range of 40 to 640 meters of the study area. A comparison between geochemical analysis of two exploratory core drilling with the depth variational model of the estimated magnetic susceptibility in the study area indicates a spatial correlation between increases in the grades of copper and gold and large variations of the magnetic susceptibility. Also, comparison between the magnetic susceptibility model and resistivity and chargeability models estimated from IP/RS data of three parallel profiles indicates a relation between sulfidic and altered mineralized zones and magnetic susceptibility variations. Therefore, the current study shows a high potential for the copper-gold mineralization in the northern Dalli index.
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