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The rhyolitic flows and sills in the extremity of Ghal'eh-chay river (East of Ajabshir, East Azerbaidjan) are exposed in the Lalun sandstone deposits. Compositionally, these rocks are rhyolite and are composed of euhedral quartz phenocrystals and subhedral perthitic orthoclases in a glassy to fine grained matrix containing quartz, k-feldspar and minor sodic plagioclases. There are not any ferromagnesian mineral except traces of decomposed and altered biotites. These rocks are highly differentiated and hololeucocratic in color and belong to the A-type series and the parental magma has calc-alkaline to shoshonitic characteristics. The REE distribution pattern in these rocks has a gentle negative slope and gives remarkable negative Eu anomaly. Negative Ba, Eu and P anomalies and non-depleted HREE pattern as well as relatively flat HREE distribution pattern show the emplacement of these bodies in a tensional within-plate regim related to initial movements of Caledonian epirogenic phase in continental crust.

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Gabbroic intrusions are located about 40 Km southeast of Fariman in Central Iran zone along the Fariman- Torbatjam road that could be seen at the end of Bardoo river and in Chahak village. Previous studies have emphasis on the age and genesis relationship between granites and gabbroic rocks. So in order to investigate this matter, granites and gabbroes  dated by using U-Pb method in Oslo University. Granites show the age of 548.3 Ma that is concarrent with the formation of schists during high temperature metamorphism in Fariman area. Dating of gabbroic rocks suggest an age of 471.14 ±0.85 mainly Early Paleozoic age that is younger than magmatism formed granites. Introducing Ordovician plotunism in this area is very important for reconstruction of Caledonian event. It seems that the formation of Gobbroic rocks is as a result of a short orogeny event due to opening of paleotethys during ordovician and Silurian.