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Tabriz Basin has had extensive Cenozoic and Quaternary volcanic activity and lies in NW Iran within the collision zone of the Arabian and Eurasian plates. Formations in the region consist of siliciclastic rocks of the Miocene age (Upper red formation), along with younger dacite volcanic rocks. The Bahlul Daghi volcanic dome in the south of Spiran is variable in terms of the composition between dacite to rhyolite. It usually contains porphyry texture with phenocrysts of quartz, plagioclase, sanidine, hornblende and biotite. Field observations clearly show that they penetrate into the sequence of the Upper Red Formation, so they are younger than these units. In order to determine the exact age of volcanic rocks, Ar-Ar age dating was performed on seven biotite crystals isolated from the dacite sample. This analysis yielded saddle-shaped age spectra with initially old apparent ages followed by decreasing to a well defined plateau age, from which a precise age for volcanic rocks can be determined. Our new ⁴⁰Ar/³⁹Ar isochron results date this volcanic rocks 2.05±0.15 Ma.

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The Grouh area is located about 19 km north-east of Sarduyeh city in Kerman Province. The major lithological units in this area include Eocene andesite and andesitic basalt. Oligo-Miocene intrusive units include diorite, quartz diorite and granodiorite; while pyroclastic units include tuff and breccia. The alteration in the Grouh area is remarkable due to the penetration of the intrusive masses into the volcanic rocks. Propylitic, phyllic and  potassic alteration in the northern and southern parts of the range is widely spread. Copper ore deposits (chalcopyrite and malachite) are found in small outcrops in the microporous porphyry granodiorite in the northeastern region. Mineralization can be seen only in hypogen part, and evidence of supergene zone is very weak.. The presence of potassic alteration at the surface as well as the rough topography of the area indicates a high upsurge and severe erosion in the studied area, which possibly led to the transfer of copper to the downstream areas.

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Qarah Gol area is located in Ahar-Arasbaran metallurgical zone in Ardabil Province, Meshkinshahr city in Moradloo section. The oldest rock units in the study area are related to the Cenozoic (Eocene), which consists of volcanic breccia. In this area, microquartzdiorite have penetrated into volcanic and pyroclastic rocks and alteration and mineralization have taken place on a weak scale. The results of Aster image processing, using absorption bands and selection of the best ratio color composite (5 + 7.6, 9.8, 4.5) respectively for the detection of argillic, phyllic and propylitic alterations, as well as using techniques such as principal component analysis and spectral angle mapping indicate that associated alterations in the central part of this deposit is consistent with petrographic studies in Qarah Gol area. Field studies have shown that the results of Spectral Angle Mapper (SAM) have performed better than the principal component analysis (PCA) in the detection of alterations.