| Xiangshan-Weiningbeishan region of Ningxia is located in the connection place of northeast corridor transitional belt of north Qilian folds system, south edge of the Alashan block and west margin of the Ordos block, and it is situated in the intersectional part of the EW trending tectonic zone of the western China and SN trending tectonic zone of the eastern China. Also, Xiangshan-Weiningbeishan region, which has been an important part of arc-shaped thrust-nappe structure system of the southern Ningxia, is always the highlight to work for metallic mineral exploration, due to its especial tectonic and complicated geological background. With the progress of mineral exploration, a great number of small iron deposits have been found in the field of Xiangshan mountain and Weiningbeishan mountain and that of Alashanzuoqi, at the southern margin of Tengger Desert, helping the area to turn into the very significant iron deposit-froming and ore-searching perspective zone. In this zone, Zhaobishan deposit, Gujiaxian deposit and Shigaigou deposit are the most typical iron deposits, which have been affected by different geological unit and specific mineralization. By virtue of comprehensive research on mineralization, geological background, geochemistry, geophysics and the typical iron deposits of Xiangshan-Weiningbeishan region of Ningxia. In this paper progresses have been made. They are as follows.(1) Resulted from 4 periods of thrusting nappe events, the complicated and giant arc-shaped structure system of the area have been openning the way to iron mineralization.(2) Iron mineralization ruled by the sedimentary formation. The main iron formation included the chert and siliceous dolostone sequence of the medial Ordovician Xiangshan Group and the Carboniferous as well as the clastic rocks and carbonate formation of the Carboniferous, rich in Fe, S, Ca, Si, et al.(3) The arc-shaped thrusting nappe system that consisted of a series of large-scale faults and folds, have taken control of the distributions and shapes of the ore bodies. And the ore-controlling and host structures is composed of the secondary folds and faults, the interlayered fracture belts, and the fissures caused by compression between the soft rocks and the hard ones. That does a find job of providing direct migration channels and deposition spaces for iron mineralization.(4) The conformation of the iron deposits are on intimate terms with the sedimentary environment and paleogeography of this area. Iron formations or iron-bearing strata occurred in the rocks of transgression sequence. The salty lagoon facies rocks of the lower Carboniferous resulted from the deposition occurred in a comparatively closed or semi-closed inland paleo-basin or paleo-bay, around where ore-forming materials(including Fe) derived from paleo-continent were adequate for supply, to build up an advantageous sedimentary environment and paleogeographic condition.(5) According to the analysis on the geological setting of ore-forming processes, the characteristics of ore, the structure and composition of iron minerals and the features of the the wall-rock alteration, it concluded that Gujiaxian iron deposit and Shigaigou iron deposit had their origin in the processes of oxidation and leaching in the shallow surface, and that Zhaobishan iron deposit resulted from the low-temperature hydrothermal activation and the oxidation of the shallow surface.
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