نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشگاه شهید بهشتی
2 دانشکده علوم. دانشگاه شهید بهشتی. دانشکده علوم زمین
3 دانشکده زمین شناسی، دانشگاه تهران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Northern Hired mining area with an area of about 25 square kilometers is located in South Khorasan province and 140 kilometers south of Birjand city. in this area, intermediate to acidic intrusive masses with the composition of granodiorite to granite have penetrated and affected the Tertiary sedimentary-volcanic sequence. The most important changes that have been detected on the surface are:1) quartz-tourmaline-sericite, 2) carbonate and 3) propylitic. In observations and field studies with 20 times magnification and also petrographic and mineralogical studies: hematite, limonite, goethite, specularite, pyrite, pyrite oxide, chalcopyrite, bornite, malachite, quartz, malachite, Milky quartz, azurite, tourmaline, cinnabar, stibnite, realgar, orpiment, galena, sphalerite have been observed in different parts of this area. Mineralization in faulted and altered zones is veined. In the analyzed samples from this area, 57 samples have values higher than 100 ppb of gold, of which 17 samples have values higher than 500 ppb of gold and a maximum of 3362 ppb of gold and 24 samples have values between 200 and 500 ppb of gold. By drawing a cluster diagram of the analyzed elements and considering the correlation of aluminum and titanium elements as well as chromium and nickel, it can represent a subduction environment. Also, the correlation of iron and sulfur elements with gold element indicates epithermal mineralization
کلیدواژهها [English]
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