نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه زمینشناسی، دانشکده علوم، دانشگاه فردوسی مشهد، مشهد، ایران
2 -مرکز پژوهشی علوم جغرافیایی و مطالعات اجتماعی، دانشگاه حکیم سبزواری، سبزوار، ایران -هستۀ پژوهشی فلزات سنگین، دانشگاه حکیم سبزواری،
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
The Arghash region, situated in the southern sector of the Sabzevar ophiolitic belt, represents a key area for investigating tectonomagmatic evolution and mineralization potential within paleo-oceanic settings. This study examines the geochemical characteristics, petrogenesis, and alteration signatures of the volcanic and plutonic rocks in the region, with the aim of constraining their tectonic environment of formation and assessing their relationship to submarine hydrothermal systems. The findings indicate that the pillow lavas exhibit geochemical affinities akin to E-MORB (enriched mid-ocean ridge basalt), and were derived from an enriched mantle source within an extensional regime associated with oceanic crustal spreading. In contrast, the mafic intrusive bodies and dykes display IAT (island-arc tholeiite) characteristics, implying the influence of subduction-related components during the basin’s evolutionary history. Evidence of spilitic alteration, extensive pyritization, malachite impregnation, and fossilized chimney-like structures points to the activity of a submarine hydrothermal system and the circulation of hydrothermal fluids within the basaltic crust. Despite these indicators, the absence of massive sulfide mineralization suggests that the Arghash hydrothermal system likely did not attain the stage of economic sulfide concentration. This may be attributed to incomplete system evolution, insufficient concentration of metal-bearing hydrothermal fluids, or the lack of preservation of the ore-bearing portion of the system. The results of this study demonstrate that E-MORB basalts can be associated with VMS (volcanogenic massive sulfide) systems in suitable settings; however, the formation of an economic deposit requires complete system evolution and effective focusing of ore-forming fluids.
کلیدواژهها [English]
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