TITLE:
A preliminary study of the anisotropy of magnetic susceptibility (AMS) of Boroujerd granitoids, Sanandaj-Sirjan Zone, West Iran
AUTHORS:
Jamal Rasouli, Vahid Ahadnejad, Dariush Esmaeily
KEYWORDS:
Gousheh; Boroujerd; Sanandaj-Sirjan; Iran; AMS; Granitoid; Neotethys
JOURNAL NAME:
Natural Science,
Vol.4 No.2,
February
22,
2012
ABSTRACT: The Boroujerd pluton (ca 175 Ma) was emplaced in the Sanandaj-Sirjan zone (SSZ) active margin of Central Iran consists of monzogranite, granodiorite, and quartz-diorite. Microstructural studies show a continuum from magmatic to (sub) mylonitic deformations fabric. Intensity of deformation decreases from W-NW to E-SE. The over- all magnetic fabric of the pluton yields steep NW- SE striking foliations and sub-horizontal lineations plunging both to the northwest and south- east. These features imply that during intrusion of the pluton, a NW-SE trending stretching was dominant. This stretching is ascribed to the trans- pressive deformation of the overriding SSZ during northeastward subduction of the Neotethys under the Iranian plate. The NW-SE trending lineations of the Gousheh pluton (ca 35 Ma) suggest that the transpressive regime was ongoing from the Mesozoic to late Eocene.