Geology, Altration, Mineralization and Geochemical Study in Copper Mine, Gholcheshmeh Area, South of Neyshabor
Message:
Abstract:
The Golcheshmeh copper deposit is located in the north-easth of Iran (south of Neyshabour) at the margin of Sabzevar Structural Zone. Based on geological and labratory studies, the outcroped rocks consist of Eocene volcanic rocks such as andesite, basaltic- andesite and basalt, that associated with the sedimentary and volcanosedimentry rocks including limestone, tuff and breccia. The alteration is hosted andesitic layers that includes carbonatization, propylitic and less argilic and sericitic. The carbonatization zone is the most important alteration zone in this area. Mineralization mainly occurs in Eocene or younger volcanic rocks as vein- veinlets, amygdaloidal fillings and some replacement and disseminated styles. According to the minerallographic studies, the main ores containing copper are divided into oxide and sulfide types. Mineralization mainly consists of oxide phases and can be seen as contamination of surface fractures and pores or voids filling in host rocks. The main oxide minerals are malachite, azurite and chrysocolla and sulfide minerals are chalcocite, covellite, with minor chalcopyrite, bornite, digenit and also native copper. Chalcocite is the most abundant sulfide ore in this area. There are probably two generations: The first generation is a primary ore that was formed directly in joints, cracks, and fractures from the ore-containing solution and currently is replaced covellites, and the second generation is chalcocite that was probably formed from the conversion of bornite and chalcopyrite through substitution and under supergene conditions. In most cases, the observed intergrowth between copper ores suggests the multi-stage mineralization in this region. Geochemical studies based on minor and trace elements obtained from this research indicate that the igneous rocks in this region were characterized by the calc-alkaline basalt characteristics and in terms of tectonic setting, could be attributed to subduction zone-related continental arc magmatism. In addition, based on the results of the analyses of trace and rare earth elements, the high amount of Nb (more than 16 ppm), Rb-rich, (Zr / Nb)N (less than 2 and between 0.7 to 0.46), could be an indication of contamination of magma with continental crust. The absence of Eu anomaly suggests a broadly defined melting conditions at oxidation state. On the basis of this study and with respect to some evidences such as tectonic setting, host rock types, structure and texture of ore body, mineral paragenesis, shape of the ore body and associated elements, this area is comparabale to a Manto type deposit located in Chile regardless of some differences. Thus, it is suggested that the Golcheshmeh copper mine classified a Cu- Manto type deposit.
Language:
Persian
Published:
Iranian Journal of Geology, Volume:10 Issue: 40, 2017
Pages:
1 to 19
magiran.com/p1675380  
دانلود و مطالعه متن این مقاله با یکی از روشهای زیر امکان پذیر است:
اشتراک شخصی
با عضویت و پرداخت آنلاین حق اشتراک یک‌ساله به مبلغ 990,000ريال می‌توانید 70 عنوان مطلب دانلود کنید!
اشتراک سازمانی
به کتابخانه دانشگاه یا محل کار خود پیشنهاد کنید تا اشتراک سازمانی این پایگاه را برای دسترسی نامحدود همه کاربران به متن مطالب تهیه نمایند!
توجه!
  • حق عضویت دریافتی صرف حمایت از نشریات عضو و نگهداری، تکمیل و توسعه مگیران می‌شود.
  • پرداخت حق اشتراک و دانلود مقالات اجازه بازنشر آن در سایر رسانه‌های چاپی و دیجیتال را به کاربر نمی‌دهد.
دسترسی سراسری کاربران دانشگاه پیام نور!
اعضای هیئت علمی و دانشجویان دانشگاه پیام نور در سراسر کشور، در صورت ثبت نام با ایمیل دانشگاهی، تا پایان فروردین ماه 1403 به مقالات سایت دسترسی خواهند داشت!
In order to view content subscription is required

Personal subscription
Subscribe magiran.com for 50 € euros via PayPal and download 70 articles during a year.
Organization subscription
Please contact us to subscribe your university or library for unlimited access!