پلاژیوکلاز به‌عنوان شاهدی از تحولات سیستم ماگمایی کانسار مس پورفیری ظفرقند، شمال‌شرق اصفهان

زمین شناسی اقتصادی

مقاله 3، دوره 10، شماره 1 - شماره پیاپی 18، 1397، صفحه 61-76   

نوع مقاله: علمی- پژوهشی

شناسه دیجیتال (DOI): 10.22067/econg.v10i1.49039

نویسندگان

مریم امین الرعایایی یمینی^{* 1}؛ فرامرز طوطی¹؛ محمدرضا امین الرعایایی یمینی²؛ جمشید احمدیان³

¹تهران

²صنعتی اصفهان

³پیام نور اصفهان

چکیده

کانسار مس پورفیری ظفرقند در شمال‌شرق اصفهان و در بخش مرکزی کمان ماگمایی ارومیه- دختر واقع شده است. این کانسار با دارا بودن پهنه‌های دگرسانی پتاسیک، فیلیک، آرژیلیک و پروپیلیتی در نتیجه نفوذ استوک پورفیری (گرانودیوریت با سن 19-21 میلیون سال) در واحدهای آتشفشانی و نیمه نفوذی با سن 56 میلیون سال تشکیل شده است. پیریت، کالکوپیریت، بورنیت و مولیبدنیت با بافت‌های گوناگون افشان و رگه‌ای، کانی‌های سولفیدی اولیه وکوولیت و کالکوسیت از سولفیدهای ثانویه این کانسار به شمار می‌آیند. در این پژوهش با بررسی داده‌های ریزبافت‌ها و منطقه‌بندی An%-FeO در درشت بلور‌های پلاژیوکلاز موجود در این سنگ‌ها، مدل ژرف‌یابی ماگمایی برای سنگ‌های نفوذی-آتشفشانی میزبان کانسار مس پورفیری ظفرقند پیشنهاد می‌شود که تبلور در آشیانه ماگمایی پوسته‌ای اساساً توسط فرآیند رشد- انحلال و اختلاط ماگمای مافیک در پوسته انجام شده و احتمالاً مقادیر زیادی مس برای کانی‌زایی در این کانسار فراهم کرده است.

کلیدواژه‌ها

پلاژیوکلاز؛ مدل ژرف یابی ماگمایی؛ مس پورفیری ظفرقند؛ کمان ماگمایی ارومیه دختر

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