Document Type : Research Paper

Authors

• Kh. Khoshnoodi
• S. Ziapour

Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.Box: 11365-8486, Tehran - Iran

Abstract

Khoshoumi Anomaly 6 is one of the important uranium deposits in the Bafq-Saghand metallogenic belt in the Central Iran zone. The gneiss is the main host of uranium mineralization in block 1 of Khoshoumi Anomaly 6, and based on field emission electron microscopy studies, two stages of uranium mineralization including primary mineralization (hypogene) and uranyl silicate (supergene) were observed in it. Primary uranium minerals in the hypogene zone include uraninite with minor amounts of thorouraninite, brannerite, and uranothorite. Uranyl silicate mineralization occurred along fractures in the form of boltwoodite and soddyite, and subsequently boltwoodite underwent alteration and turned into sodium-boltwoodite and uranophane. Based on field evidence and mineralogical studies, probably meteoric fluids with neutral to alkaline pH and low temperature during movement leached uranium, silicon, potassium, sodium and calcium from the gneiss and along fractures as uranyl silicate minerals with calcite, clay and chlorite have been deposited. Based on field evidence and mineralogical studies, it is likely that circulating meteoric fluid of with neutral to alkaline pH and low temperature leached uranium, silicon, potassium, sodium, and calcium from the gneiss and They deposited as uranyl silicate minerals accompanied with calcite, clay and chlorite along the fractures. The presence of paragenesis calcite with uranyl silicates indicates the transport of uranium in the form of uranyl carbonate complexes in the fluid.

Keywords

• Uranium
• Uranyl silicate
• Khoshoumi
• Bafq-Saghand

Main Subjects

• GEO SCIENCES