مطالعه دگرشکلی غیریکنواخت در پهنه‎ها‎ی برشی کمربند دگرگونی سنندج- سیرجان، نیریز

نوع مقاله: مقاله پژوهشی

نویسندگان

1 استادیار دانشگاه تحصیلات تکمیلی صنعتی و فناوری پیشرفته کرمان، ایران.

2 دانشیار بخش علوم زمین، دانشگاه شیراز، ایران

3 . دانشیار دانشگاه تحصیلات تکمیلی صنعتی و فناوری پیشرفته کرمان، ایران

4 دکتری زمین‌شناسی، داشنگاه خلیج فارس، بوشهر، ایران

چکیده

چکیده:
مطالعات ساختاری و جنبش شناختی بر روی سنگهای دگرشکل شده کمربند دگرگونی سنندج- سیرجان به عنوان بخشی از کوهزاد زاگرس نشان میدهد که دگرشکلی در شرایط رخساره شیست سبز- آمفیبولیت صورت گرفته است. جهت برش غالب top-to-the-SEبوسیله ساختارهایی مانند بودینهای نامتقارن، میکاهای ماهی‎گون، پورفیروکلاستهای غلافی، چینهای کشیده، رخکنگره­ای نامتقارن و بافتارهای محور c کوارتز تأیید می­گردد. واکاوی عدد تاوایی جنبشی متوسط با استفاده از روشهای مبتنی بر بافتار کوارتز و پورفیروکلاستهای چرخیده نشاندهنده وجود 44 درصد برش ساده و 56 درصد برش محض در طی دگرشکلی شکلپذیر برش عمومی می‌باشد که در ارتباط با رژیم جریان ترافشارشی مایل بوجود آمده است. مقادیر متغیر برش ساده نسبت به زمان دگرشکلی نشان دهنده آنست که در مراحل ابتدایی دگرشکلی مولفه برش محض نقش اساسی داشته و با پیشرفت دگرشکلی مولفه برش ساده افزایش یافته است.

کلیدواژه‌ها


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