Iranian Journal of Geophysics

Iranian Journal of Geophysics

Identification of copper-gold porphyry mineralization zones using airborne magnetic data, a case study of the British Columbia study area, Canada

Articles in Press

Document Type : Research Article

Authors
Moslem Jahantigh 1
Hamid Reza Ramazi 2
1 Ph.D. Student in Mineral Exploration, Amir Kabir University, Tehran, Iran
2 Professor, Mineral Exploration Group, Amir Kabir University, Tehran, Iran
10.30499/ijg.2026.425940.1553
Abstract
The study area are located in British Coloumbia in Canada. This area consist of numerous cu- Au porphyry indication. Most of studied area is covered with sedimentary rocks. Igneous rocks caused caused metamorphosis in sedimentary rocks. Igneous rocks were intruded along faults. The most of volcanic rocks include of basalt and volcano sediments. The ignous rocks in the study area include of gabbro, diorite, volcanic rocks, ultramafic roks and…Airborne magnetic data have been used in British Columbia in Canada to interpret and extract lineaments and geological structures. Aeromagnetic method is a well known method to extract geological formation and structures. Different filter can be applied on aeromagnetic data to extract geological information. For example tilt angle method can be used to extract linear structures. First vertical derivative can be used to extract near surface structures and bodies. CET grid analysis is useful tool to extract lineaments automatically. This method distinguishes alteration zone in porphyry mineralization very well. The high alteration zones can be related to potassic alteration and igneous rocks and low ateration can be relate to phyllic alteration. In this article, the automatic method is used to extract the structures. Then reduction to pole transformation was done on total magnetic intensity map. Reduction to the pole (RTP) is a standard part of magnetic data processing method, especially for large-scale mapping. RTP operation can transform a magnetic anomaly caused by an arbitrary source into the anomaly that the same source would produce if it is located at the pole and magnetized by induction only. The study area is located in Canada and it is important in terms of copper-gold mineralization of Haer porphyry. Geosoft software was used to extract porphyry structures and intrusions from the Ecntre of Exploration Targeting(CET). High magnetic anomalies were extracted as porphyry intrusion from reduction to pole map and with automatic method. High magnetic anomalies in first vertical derivative were extracted as near surface structure. Lineament structures were extracted with automat method and with CET grid analysis menu in Geosoft software. The results show that the structures in the studied area mainly have a northwest-southeast trend, but sometimes structures with a north-south, east-west and northeast-southwest trend are also observed in the area. The areas with high density of magnetic lines are consistent with porphyry copper indices in the study area. The matching of porphyry copper indices with magnetic structures confirms the effective role of faults in the formation of porphyry copper deposits.
Keywords
Porphyry
centre of exploration targeting
British Collumbia
aermagnetic data

Subjects

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Iranian Journal of Geophysics

Articles in Press, Accepted Manuscript
Available Online from 23 February 2026