Interpretation of magnetometry data in Northwest of Natanz, Central Iran

Study area is located in the northwest of Natanz in Isfahan province, in the Uromieh-Dokhtar volcanic belt. It s lithology consists of granodiorite, diorite, dolomitic limestone of Shotori formation and magnetic veins. The genesis of iron mineralization is epigenetic. Mineralization is along with Natanz fault with NWSE strike and 40° to 90° dip. The main vein has 12m length and 5m width. According to field observations, five veins are exposed on the surface. Magnetometry studies were done in 26 profiles by average distance of 25m and 5m points distance (N-S trend) perpendicular to trend of mineralization. In this study, TMI (total magnetic intensity, by magnetic field range between 46510 and 48039 nT), residual magnetic anomaly (by magnetic field range between - 1159 and + 629 nT), returned to pole (RTP), upward continuation, analytic signal, Euler depth estimate (structural Index) are used for determining magnetic anomaly and estimation of vein’s depths. Result s interpretation confirmed that magnetic anomaly is located along with the Natanz fault with NW-SE strike. Based on results of Euler depth estimation and 3D inversion of magnetic data, the depths and extension of the structures were determined which has a good correlation with the geological information. The average depth of the veins was estimated 40 to 50m.