Geochemical and tectonomagmatic investigation of gabbros in southwest of Shahr-Babak, Kerman province

Abstract

The studied intrusions with parallel northwest – southeast trend, are located in southwest of Robat Village, Shahr-babk. General exposure of the northern trend is massive and consists of urallitized gabbro, hornblende gabbro, olivine gabbro, anortosite and plagiogranitic dikes and are highly altered. The composition of rocks in the southern trend consists of dunite, pyroxenite, olivine gabbro and troctolite and is very fresh and has cumulate textures. On the base of chemical analysis, using of ICPAES and ICP-MS method, these rocks are located in the low potassium tholeiitic filed. Also by using of tectonic setting diagrams, the studied intrusions display extensional marginal basin characteristic. The rare and trace elemental pattern of these rocks have a descending trend from low to high elements and the examples of anomalies are the positive crest of Sr and the negative crest of Nb. Also the study of REE trend show that the tholeiitic magma may have formed in the upper pridotitic mantle.

Keywords


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