| Qicun iron deposits is located in the east of taihang uplift belt, the northern section ofHandan-Xingtai iron deposits metallogenic belt, the tectonic location is located in geotectogenewhich is the southern of Zanhuang uplift belt in the central section of north China platform,and is one of the important skarn iron deposits concentration area in the Handan-Xingtai area.The regional tectonic characteristics of the area is the development of north-northeast andnorth-south to fracture structure, the direction of the overall geological structure is northwest,The northwestern end of anticlinal structure raise and incline toward the southeast, andXihaozhuang iron deposits and Xiaotunqiao iron deposits constitute together the northwesternof metallogenic tectonic magmatic belt.The iron deposits resource is rich, good quality, highgrade, and important industrial value, the study of the iron deposits in Qicun has importanteconomic value and prospecting significance.Combining with field investigations,this paper is based on making full use of previous data,which starts with geological features and ore-controlling structure of Qicun ore deposits.Baijian iron deposits and Fenghuangshan iron deposits as a typical iron deposits was analyzed,and through the stable isotopes and fluid inclusions tests of rock ore and so on.The skarn irondeposits were further studied, discussed the ore-forming material sources of Qicun ore deposits,and presumed the prospecting direction. The main achievements and understanding are asfollows:1. Wall-rock is the Middle Ordovician limestone Majiagou.The main rock types aredolomitic limestone, and dolomite lime. They belong to calcium magnesium carbonate,and arethe most favorable wall-rock. The chemical composition of MgO and Majiagou groupbrecciated limestones related to mineralization, as the most important rock prospectingprospecting layer.2. Field and laboratory study shows that the wall-rock alteration zone has obviouszonation. From the intrusion to carbonate rock,the alteration of wall rocks can be divided intosix alteration zones:primary rock, albitization zone, albitite zone, skarn zone, ore zone andmarble zone.There are gradual changes between the five alteration zones. Albitization zone andalbitite zone correlate closely to mineralization. The size of ore is in direct proportion toalbitization zone and albitite zone in scale and scope. Mineralization occurs mainly in skarnstage. Diopsidezation and phlogopitization are closely related with the mineralization.Albitization, diopsidezation and phlogopitization are the main indications of wall rockalteration for prospecting.The interface morphology of rockmass and surrounding rock plays an important controlling role in ore deposit, fracture, fault, and weak interlayer are places whichore fluid aggregates metallogenic belt.Complex contact boundary which stop and detain someore fluid only form small ore body.3. To the source of ore-forming materials research shows that the main source ofore-forming materials is the precipitation of iron objects which from the albitization of rockmass around the ore bodies and iron objects that from deep source and magnetite quartziterocks in the old crystalline base-ment, which plays a role in the increase of iron content in themagma, but is not the main source of ore-forming materials.4. The precipitated iron objects of albitization was mainly in the hydrothermal fluids（Na,K）3[Fe3+（Cl,F）6],（Na,K）2[Fe2+（Cl,F）4],（Na,K）[Fe3+（Cl,F）4] complex formsof migration. Diopside and carbonate which are rich in calcium caused the precipitation of iron. |
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