نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه اقیانوسشناسی، دانشکده علوم دریایی، دانشگاه دریانوردی و علوم دریایی چابهار، چابهار، ایران
2 مدرس زمینشناسی، آموزش و پرورش منطقه آزاد چابهار
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
The Bajkan-Durkan complex is located in southeastern Iran, within the Makran accretionary wedge. Despite different interpretations, the origin and tectonic setting of the intrusive rocks of this complex remain unclear and controversial. The Bajakan-Dorkan complex is composed of metamorphic-sedimentary basement rocks overlain by intermediate- to acidic-intrusive rocks and carbonate deposits. Based on petrological studies, intrusive rocks have been classified into three groups: granite, diorite,, and plagiogranite. Potassium feldspar (3 mm), plagioclase (< 0.1 mm), and quartz, associated with amphibole, biotite, zircon, ilmenite, and hematite, are the main rock-forming minerals. Granular and semi-granular, micrographic and granophyric textures resulting from intergrowth of quartz and feldspar, along with traces and evidence of pertitization and replacement of biotite by chlorite, have been in most samples. The Bajkan-Durkan granitoids exhibit geochemical characteristics of A-type metaluminous granites and are of high-potassium calc-alkaline magmatic nature. The enrichment in LREE and LILE associated with Nb, P, Ba, and Ti negative anomalies in these rocks indicates a melt segregated from crustal origin. Based on discriminant tectonic diagrams, the studied granites are located in the range of volcanic arc granites (VAG) and intraplate granites (WPG). Based on geographical location and petrological and geochemical characteristics, the Bajakan-Dorkan complex is the southeastern continuation of the Sanandaj-Sirjan zone, and the granites of this complex were formed in a subduction tectonic setting with local pull-apart tensions.
کلیدواژهها [English]
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