Wang and six co-authors repored in 2017 that the Ordos Basin is one of the largest proliferous basins and also one of the most important uranium-bearing basins in China. It is characterized by the coexistence of petroleum and uranium in the northern part of the basin. To understand the coexistence mechanism, more studies are called for on the genesis of sandstone-type uranium deposits in the northern part of the basin, especially on the role of hydrocarbon in uranium mineralization.
The authors investigated the relationship between uranium and hydrocarbon in the northern Ordos Basin using the methods of petrology, mineralogy and geochemistry. Our results show that the hydrocarbon seepage plays an important role in the mineralization of sandstone-type uranium deposits. It greatly affects the reduction in mineralization and the environmental rehabilitation to protect the ore body from being destroyed by the groundwater after mineralization.
The authors concluded that:
(1) The green alteration in Zhiluo Formation results from the secondary reduction of oil and gas. Its predecessor is the red sandstone formed in the oxidizing environment. The oil and gas seeping to the northeastern part of the basin could form green alteration, white alteration and pyrite as a result of the fluid-rock interaction.
(2) The oil and gas plays an important role in uranium mineralization. The seepage of oil and gas interacts with the uranium-containing and oxygen-containing fluid, reducing U6+ to U4+. After being precipitated in Zhiluo Formation, the uranium element would concentrate to form the uranium deposit.
(3) The reduction environment due to the hydrocarbon seepage can protect the ore body from being destroyed by the groundwater after mineralization.
(4) In the northern part of the basin, the Yimeng Uplift area serves as a good indicator of the hydrocarbon seepage, where the sandstone-type uranium deposits are likely to form. Its exploration potential is tremendous.
Managed & Built by I2M Consulting, LLC | © 2010-
