Geochemical Dispersion Associated with Uranium in Sandstone Roll Front Type Deposits and its Relationship to the Orinoco Oil Belt, Venezuela

In Venezuela there is a potential for the formation of uranium deposits in areas such as the Guiana Shield, the south of Eastern Basin, the Andes, and the massif of Baúl, among other areas. Of especially great interest is the exploration for uranium redox interface type (roll front) deposits in areas such as the southern part of the Orinoco Oil Belt, and north and northwest of the Guiana Shield, where groundwater-uranium weathered from the shield flows northward in the sandstones and mudstones which constitute the southern boundary of the Eastern Basin of Venezuela. The presence of gas, crude oil, bitumen and lignite of the Orinoco Oil Belt can be an effective barrier for uranium in solution, which may have precipitated at the redox interface of this groundwater. This work was based on a qualitative model describing geochemical dispersion associated with uranium deposits in sandstone, roll front type, which indicates that the daughter isotopes ²³⁸U which can migrate extensively are: ²²²Rn, ⁴He, and smaller proportion: ²²⁶Ra and ²²²Rn daughters (²¹⁴Bi, ²¹⁰Pb). The main exploration methods were established, which can be applied in areas of the Orinoco Oil Belt, north of the Guiana Shield, and areas west of there. (author)