ژئوشیمی رسوب‌های رودخانه‌ای، آب و بی‌هنجاری پرتوهای U و Thمعدن فیروزه نیشابور و تاثیر زیست محیطی آن در زندگی روستاهای منطقه

Fyrouzeh mine is located about 55 km northwest of Nyshabour in the Provice of Khorasan Razavi. The exposed rocks are mainly volcanic and intrusive with intermediate composition and all of them are altered. This mine is the first type of IOCG reconized in Iran with Cu-Au-LREE-U. Besides Cu-Au-U, this area shows As, Mo, Zn and Th anomalies. Geochemical evaluation of stream sediment with regard to environmental concern revealed high Cu anomalies.  Rocks show high uranium anomalies (up to 35 ppm) higher than the standard values (1 ppm). Airborne radiometric maps show high U and Th anomalies in a broad area. Ag, Hg and Mn show anomalies within the stream sediments. Cu, Pb, Zn, Ag, Ni, Mn, Sb, Hg, and U content of both drinking and agricultural water are fourtunatly within the range of standard, only two samples have higher As content (more than 10 ppb).  High level of U-Th radiation and contamination of stream sediment with respect to Cu, Hg, Ag, Mn and agricultural water to As are important environmental issues and people health therefore they need to be study.