Petrology and geochemistry of andesitic dykes in the north of Rabor, Kerman province

Abstract

The study area is located in the Kerman province, 10 Km north of Rabor. Geologically, the area is situated in the eastern section of Dehaj-Sarduiyeh belt which is a part of Urumieh-Dokhtar magmatic assemblage. The dykes were intruded in the Eocene pyroclastic rocks and Pliocene sedimentary units. Petrographic studies show that these rocks are andesitic in composition. Mineralogically they are composed of plagioclase, hornblende, biotite and clinopyroxene. Phenocrysts of plagioclase show disequilibrium textures such as oscillatory zoning and sieve texture. Hornblende and biotites are affected by opacitization process. The dykes have mainly hyalloporphyritic, microlitic porphyric and flow textures. Based on geochemical studies, the rocks show enrichment in LREE rather than HREE The lack of significant Eu anomalies in REE patterns indicates oxidation state of magma during crystallization. These properties are signatures of calc- alkaline series formed in a volcanic arc setting.                                                                                                    

Keywords


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