Natural uranium (U) occurs as a mixture of three radioactive isotopes: U, U, and U. Only U is fissionable and makes up about 0.7% of natural U, while U is overwhelmingly the most abundant at greater than 99% of the total mass of U. Prior to the 1940s, U was predominantly used as a coloring agent, and U-bearing ores were mined mainly for their radium (Ra) and/or vanadium (V) content; the bulk of...

The effects of breccia pipe uranium mining in the Grand Canyon watershed (Arizona) on ecological and cultural resources are largely unknown. We characterized exposure biota to co-occurring ore body elements during active production at a site where had recently concluded. Our results indicate that have taken up other (e.g., arsenic, cadmium, copper, molybdenum, uranium) from surficial contaminat...

The Oklo phenomenon, natural fission reactors which had taken place in Gabon about 2 billion years ago, provides one of the most stringent constraints on the possible time-variability of the fine-structure constant α. We first review briefly what it is and how reliable it is in constraining α. We then compare the result with a more recent result on the nonzero change of α obtained from the obse...

The harsh environment of high-latitude areas with large amounts snow and ice cover makes it difficult to carry out full geological field surveys. Uranium resources are abundant within the Ilimaussaq Complex in Narsaq region Greenland, where uranium ore body is strictly controlled by Lujavrite formation, which main ore-bearing rock complex mass. Further, aggregations radioactive minerals appear ...

Soil, water and sediment samples collected from in and around Jaduguda, Bagjata and Turamdih mines were analyzed for physicochemical parameters and cultured, and yet to be cultured microbial diversity. Culturable fraction of microbial community measured as Colony Forming Unit (CFU) on R2A medium revealed microbes between 10(4) and 10(9) CFU/g sample. Community DNA was extracted from all the sam...

Uranium reserve estimates in ore deposits can be significantly impacted by 226 Ra/ 238 U disequilibria arising from the differential mobility of uranium and radium during groundwater transport. 1D reactive transport models were developed to investigate long-term effects retention processes (UO 2(am) precipitation, U(VI) Ra sorption on smectite, co-precipitation with barite) repartitioning forma...