اكتشاف ژئوشيميايي رسوب هاي آبراهه اي اورانيوم در منطقه ناريگان استان يزد

Stream-Sediment Geochemical Exploration for Uranium in Narigan Area Central Iran

Uranium depo sits of Iran occ ur mainly in the Central Iran zo ne. Several uranium deposits have been discovered in thi s zone. Th e Nari gan area is one of the most important uranium mineralized area in this zo ne. The uranium bearing sequences in thi s area arc contained in the plutonic to volcanic rock s of Narigan which intruded to the Pre-Cambrian pyroclastics roc ks. Plutonic and volcanic rocks are granite, ryolite and volcanocl astic , Diabasic dyk es have been intruded to these igneous rock s. The plutonic and volcanic rock s have been covered by Cretaceous lime stons which seem to be younges t the rock s in this area . The aim of our proje ct is to develop a regional exploration strategy for uran ium in these igneous rocks . A grid-based sampling was planned following the results of the previous geochemical mapp ing at a scale of 1:100.000, integrated with geophysical data and alteration zones and outcrop of intrusive rocks. Th e following results arc based on geological, and stream geochemica l explorations in 1:20000 sca le of this area . During this study 121 samples were collected from the stream sed iments of <80 mesh for final sampling. Ten percent of the samples were used for checking laboratories enolʹs. The samples were co llec ted acc ordin g to conventi onal methods from 30-40 ern depth of stream sediments. Fin ally, geochemical and radiometric data were combined and the results introduced 3 anomalies in the Narigan area