Miguta Faustine Ngulimi (Tanzania)

Thesis title:  Geochemical examination of surficial soil overlying uranium deposit in Manyoni, Central Tanzania and its associated geologic depositional environment.

Supervisor:  Professor Hiroaki Ishiga (2014-2016).

Uranium deposits are widely distributed in central, western and southern parts of Tanzania mainland, East Africa. Manyoni uranium deposit is one of the deposits located in central Tanzania. It is described as a surficial type uranium deposit (Bianconi and Borshoff, 1984). It has been revealed that the source of uranium mineralization was related to the surrounding granites, which are enriched in uranium concentrations (Bianconi and Borshoff, 1984). This uranium deposits is known as the largest deposits of the world (IAEA, 2009). Surficial uranium deposits are normally defined as young mineralization (Tertiary to recent), which occurs, in surface sediments or soils (IAEA, 2009). Secondary precipitates in these deposits are calcite, gypsum and dolomite (Rob et al, 2009; Carlisle, 1984).

Aims of the Study:

The study research is aimed at analyzing the geochemical compositions of major and trace elements of the surface to shallow depth (0 - 2.5 m) soils overlying the Manyoni uranium deposit. Also, the study can test the radiation exposures near ground surface.

Specific Objectives:

1. to identify the trace and major elemental composition of the top to shallow depth soil that overlie the uranium deposit,
2. to identify the depositional environment of the uranium mineral ores,

Significance:

The result will be useful to understand the effects of hazardous chemical elements to the surrounding environments. Also, result of this research can be used as background data for monitoring uranium mining development and management. On the other hand, this research will outline some environmental precautions for uranium ore extractions with respect to the geochemical composition of the soil.

References:

Bianconi, F. and Borshoff, J. (1984), Surficial Uranium occurrences in United Republic of Tanzania. Surficial Uranium Deposit, IAEA, VIENNA, 231 – 235.

Carlisle, D. (1984), Surficial uranium occurrences in relation to climate and physical setting. Surficial Uranium Deposit, IAEA, VIENNA, 25 – 35.

Rob, J. Bowell., A. Barnes., J. Grogan. and Matthew Dey, 2009, Geochemical control on Uranium precipitation in calcrete palaeochannel deposits of Namibia. SRK publications, June 2009, 1 – 4.