Baghak mine (central part of Sangan mines): The metallogenic relationship between minerals containing rare earth with radioactivity

According to strong evidence based on existence of relationship between rare earth elements and radioactivity, sampling from Baghak anomaly in Sangan mine (NE of Iran, in Khorasan Razavi province and near the border of Iran-Afghanistan) has been carried out based on radioactivity and radiation measurement methods. In fact,the goal of this study, in addition to the presence or absence of such relation in a skarn mine, is introducing and providing an exploration method and optimal sampling pattern to explore REE and investigation of REE distribution in Baghak mine. Results of the microscopic studies and statistical analyses show that there is an acceptable correlation between these elements in Sangan Fe-skarn mineralization in addition to presence of such relation in central Iran’s mineralization. Chondrite normalized REE pattern shows enrichment of LREE and a positive pattern close to flat HREE due to the entry of LREE ions into allanites network. Moreover, REE patterns show negative Eu anomaly in whole rock. Primitive mantle normalized multi-element patterns are enriched in LREE (La, Ce, Pr, Nd), large ion lithophile (LILE, Cs, Rb, Ba, K), radioactive elements (Th, U), and are strongly depleted in high field strength elements (HFSE, Y, Zr, Ta, Nb, Ti) and HREE (Yb, Lu) compared to the primitive mantle. These features are typical of the subduction related magma.