Lens-shaped ore bodies, hosted at depths of 200-300 m at the base of a sequence of Jurassic sedimentary rocks at the eastern margin of the Shengyuan basin. The primary uranium mineralization, consisting mainly of uraniferous collophane, is overprinted by a small-scale U-Mo mineralization.

It is a large-sized U deposit with estimated resources exceeding 3000 t U with an average ore grade of 0.112%. Uranium mineralization is chiefly hosted in Member 3 of the Ehuling Formation, particularly in its middle-lower portions. Lithologically, the ore-bearing volcaniclastic-sedimentary succession shows a clear fining-upward trend, i.e., tuffaceous conglomerate at the base passes upward into medium- to coarse-grained tuffaceous sandstone, and finally into fine-grained siltstone and shale at the top. Two major faults, F1 and F2, in the eastern part of the deposit acted as syn-sedimentary faults, strongly influencing facies and thickness variations within the ore-hosting units. All economic U orebodies at Xiongjia are confined within the block bounded by F1 and F2h. The No. 11 orebody, for example, generally conforms to stratification, although local cross-bedding and continuity of mineralization are observed. Orebodies mostly occur at 200–350 m depth and are stratiform to lenticular with gentle dips. Individual lenses are typically 90–130 m in length, with an average thickness of ∼3 m and a maximum thickness up to ∼27 m. The U mineralization can be divided into two stages, i.e., the dominant U-P mineralization in the early stage and the inferior U-Mo mineralization in the late stage.

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