Writers : Esmaeli,Dariush;Razaghi,Mohammadreza
Refference : 10th Symposium of Geological Society of Iran-Tehran
Publishing Year : 1385

Abstract :

The Ghoche Palarig area is located in the NE of Kashmar province and belongs to the Central Iran Zone (CIZ). The outcrops of Eocene volcanic rocks with intermediate composition (andesite to latite) associated with pyroclastics are exposed in the area. According to field and petrographic studies, three alteration zones including propylitic, argillic-silicic and quartz-sericite alteration zones are recognized.
This study focuses on mass changes during the alteration in above mentioned zones using the results of chemical analysis for 12 samples of major and trace elements which have been analyzed by means of ICP-MS method. Calculations of mass changes show:
1- The oxides including Fe2o3, Lol, Mno, Cao, Mgo and Na2o have been increased in the propylitic alteration zone, whereas, Bao, K2o and Sio2 oxides have been decreased. As well as, HFSE have not significant mass change, but, LREE in comparison to HREE shows depletion.
2- In Argillic alteration zone, Fe2o3, Mgo, Cao, Mno, Bao and 1(20 oxides have been decreased, but, Sio2 have been increased due to silicification. In this zone, LREE in comparisonto HREE show enrichment. As well as, in this zone HFSE do not show any mass changes, however, Zr shows a significant enrichment.
3- Calculations of mass changes in quartz-sericite alteration zone demonstrate that Sio2 and K2o have enrichment, where as, Mno, Fe2o3, Mgo, Na2o and Cao oxides show depletion. The LREE excluding Eu have been increased, but, HREE do not have mass changes.

Subject List : Altration