نشریه علوم زمین خوارزمی

نشریه علوم زمین خوارزمی

مطالعه ژئوشیمی سنگ‌کل دگرسانی‌های گرمابی و ارتباط آن با کانه‌زایی طلا در منطقه‌ی اکتشافی شوراب، اصفهان

نویسندگان
1 دانشگاه آزاد اسلامی
2 دانشگاه فردوسی مشهد
3 دانشگاه اصفهان
چکیده
منطقه اکتشافی شوراب، واقع در بخش باختری پهنه ایران مرکزی، شواهد قابل توجهی از دگرسانی‌های گرمابی و ناهنجاری‌های عناصر کمیاب مرتبط با کانی‌سازی احتمالی از نوع ذخایر اکسید آهن طلادار موسوم به IOCG را نشان می‌دهد. پهنه­‌های دگرسانی با مجموعه‌ای از کانی‌ها شامل کلریت، کلسیت، کوارتز، بیوتیت، فلدسپار پتاسیم، آلبیت، اکتینولیت، سریسیت و تورمالین مشخص می‌شوند که با شدت‌های مختلف در واحدهای آتشفشانی مافیک تا فلسیک توسعه یافته‌اند. نسبت‌های مولی عناصر (MER) و شاخص‌های دگرسانی از جمله AI و CCPI برای ارزیابی شدت و نوع دگرسانی به‌کار گرفته شدند که گویای گذار تدریجی از زون‌های پروپلیتیک پیرامونی به مجموعه‌های پتاسیک و سدیک-کلسیک مرکزی است. ناهنجاری‌های ژئوشیمیایی عناصر Au, Cu, U, Mo, Ba, Ce, Sm و La همبستگی مکانی بالایی با انواع خاصی از دگرسانی‌ها دارند. شواهد کانی‌­شناسی و بررسی آماری شاخص­‌های لیتوژئوشیمیایی همچون غنی‌شدگی آهن، پتاسیم و عناصر نادر خاکی به همراه شاخص‌های گرمابی، نشانگر تطابق و شباهت این مجموعه ماگمایی- گرمابی با سامانه‌­های IOCG است. ترکیب سنگ میزبان، برهم‌کنش سیال-سنگ و ساختارهای منطقه‌ای تأثیر مهمی بر تنوع دگرسانی‌­ها داشته‌اند. این پژوهش چارچوبی جامع برای شناسایی آثار گرمابی مرتبط با کانی‌سازی IOCG در پهنه‌های مجموعه آتشفشانی-نفوذی ارائه داده و می‌تواند راهنمایی مؤثر برای برنامه‌ریزی اکتشافات آینده در غرب ایران مرکزی باشد.
کلیدواژه‌ها

عنوان مقاله English

Whole-rock geochemistry of hydrothermal alterations and its relationship with gold mineralization in the Shourab prospect, Isfahan

نویسندگان English

Alireza Rezaei Alishahdani 1
Alireza Jafari Rad 1
Zahra Alaminia 2
Mehran Arian 1
Hemayat Jamali 3
1 Islamic Azad University
2 Ferdowsi University of Mashhad
3 University of Isfahan
چکیده English

The Shourab prospect, located in the west of Central Iran, exhibits significant hydrothermal alteration and trace element anomalies linked to potential Iron Oxide Copper-Gold systems (IOCG) mineralization. Alteration zones are characterized by chlorite, calcite, quartz, biotite, K-feldspar, albite, actinolite, sericite, and tourmaline, with variable intensities across mafic to felsic volcanic units. Molar element ratio (MER) and alteration indices (AI and CCPI) were employed to quantify alteration processes, revealing progressive alteration from peripheral propylitic zones to core potassic and sodic-calcic assemblages. Spatial geochemical anomalies of elements such as Au, Cu, U, Mo, Ba, Sm, Ce, and La strongly correlate with specific alteration zones. Mineralogical evidence and statistical analysis of lithogeochemical indices such as iron, potassium, and rare earth element enrichment along with hydrothermal alteration indices, indicate a genetic similarity between this magmatic-hydrothermal system and IOCG type systems. Host rock composition, fluid-rock interaction, and structural controls significantly influenced alteration styles. This work provides a comprehensive framework for identifying hydrothermal footprints of IOCG mineralization in complex volcanic-intrusive terrains and contributes to future exploration strategies in the west Central Iran.

کلیدواژه‌ها English

Hydrothermal alteration
Geochemical Anomalies
IOCG systems
Central Iran
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