بررسي پراكندگي اندازه بلورهاي (CSD) گارنت در دگرگوني مجاورتي روستاي حسن آباد يزد

The Study of the Crystal Size Distribution (CSD) of Garnet in the Hassan-Abaad Contact Metamorphism of Yazd

The crystallization history of a rock is recorded by the size and the distribution of its minerals. The porphyroblast crystal size in metamorphic rocks can give notable information about its growing medium. Considering the varieties of mineralogy in the Hassan-Abadʹs skarn and high frequency of garnet porphyroblasts in different metamorphic zones and special different sizes in the first metamorphic zone of the NE skarn, the crystal size distributions of this mineral is studied. With regard to this, digital photos of cutting surface were provided and analyzed by JMicrovision software. It has been expected, two different slopes can show three suspections: 1- parent rock composition effect; 2- crystal growing time; 3- fluid flow around plutonic rock. According to the presence of clintonite, vesuvianite and garnet and as many as joints in the region, the role of fluid in growing the size of garnet porphyroblast in part of the first metamorphic zone seem to be noticeable.