Mehrab Moradi Noghondar; Mohammad Hassan Karimpour; Azadeh Malekzadeh Shafaroudi; G. Lang Farmer; Charles Stern
Volume 3, Issue 11 , December 2012, , Pages 77-96
Abstract
Najmabad is located south of Ghonabad in the province of Khorasan Razavi. This area is situated in the northern part of Lut Block. Two types of granitoid, ilmenite series (Jurassic), ...
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Najmabad is located south of Ghonabad in the province of Khorasan Razavi. This area is situated in the northern part of Lut Block. Two types of granitoid, ilmenite series (Jurassic), and magnetite series (Tertiary) are recognized in the study area. The aim of this research is to find out the age and petrogenesis of granitoid (magnetite series). The result of U-Pb zircon age dating of monzonite is 39.9 Ma (Middle Eocene time). Chemically, Monzonitic rocks are meta-aluminous to moderately peraluminous. They are classified as the magnetite-series (I-Type granitoid). Based on enrichment of LREE relative to HREE, enrichment of LILE (K, Rb, Ba and Sr) and depletion of HFSE (Nb, Ti and Ta) monzonitic magma originated in subduction zone. The average of SiO2 (66.52%), Al2O3, (15.26%), MgO (1.13%), Na2O (4.7%), K2O/Na2O (0.31), as well as LREE enrichment , positive Eu, high Sr (492 ppm), high ratio of (La/Yb)N (>13.58), Y (
