تحلیل توزیع اندازه بلور کوارتز در گارنت شیست بطور بخشی منطقه بندی شده با استفاده از تصاویر پراش پراکندگی الکترونی

نویسندگان

1 دانشگاه گلستان

2 دانشگاه لیورپول

چکیده

نمونه مورد مطالعه،گارنت بطور بخشی منطقه‌بندی شده بافتی را در دو نوع ادخال از گارنت شیست مورلیکس، شمال غربی بریتنی، فرانسه معرفی می‌کند. توزیع اندازه بلوری کانی کوارتز در هر دو نوع ادخال، زمینه سنگ و سایه استرینی اطراف  پورفیروبلاست‌های گارنت با استفاده از تصاویر پراش پراکندگی الکترونی اندازه‌گیری شده است. نمودارهای توزیع اندازه بلوری کوارتزها یک روند افزایش در میانگین اندازه از ادخال نوع اول ٦٠ میکرون، زمینه سنگ ١١٦ میکرون و سایه استرینی ٢٤٨ میکرون را نشان می‌دهند. این تفاوت در توزیع اندازه کوارتزها را می‌توان توسط فرآیندهای همچون محاصره کردن توسط پورفیروبلاست، سطح بلوری، بازپخت و مهاجرت مرز دانه توضیح داد.

کلیدواژه‌ها


عنوان مقاله [English]

Crystal size distribution analysis of quartz in sector- zoned of garnet schist using Back-scatter electron images

چکیده [English]

The studied sample presents garnet textural sector-zoning as inclusions in two types in garnet schist from Morlaix, North-West Brittany, France. Crystal size distributions (CSD) of quartz crystals were measured in both types inclusions, in the matrix and strain shadows around garnet porphyroblasts using Back-scatter electron (BSE) images. The CSD plots of quartz crystals show an increase of average in sizes from type 1 inclusion,60mm, to the matrix,116 mm, and strain shadow,248 mm,. These differences could be explained of quartzes size distribution by many processes such as capturing by pophyroblast, crystal face, annealing and grain boundary migration 

کلیدواژه‌ها [English]

  • BSE
  • quartz
  • sector- zoning
  • crystal size distribution
  • strain shadow
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