Metalogenic Regularity And Prosecting Target Of Dalaimiao Cu-Mo Polymetallic Deposit In Inner Mongolia

The survey region, an important part of Palaeo-Asia metallogenic domain, is located in the Late Paleozoic terrigenous hyperplasia belt of southeast continental margin of the Siberian plate. The survey region has complicated structure due to the multi-period structural movement in geological history. The main tectonic line mainly strikes NE trending, secondly NW trending, which is also the main ore-controlling structure. The regional stratigraphy is composed of Ordovician system, Devonian system, Carboniferous system of Palaeozoic and Jurassic, the Cenozoic and Quaternary system.Through the analysis of regional geological features, geophysical and chemical anomaly characteristics, combined with dating of typical deposits, summarize the metallogenic regularity and prospecting method of copper-molybdenum deposit in this area, and predictic metallogenic target area.According to the field investigation and further research work, main achievements are as following:1.The Cu-Mo deposits in this region are mostly porphyry type deposits and magmatic hydrothermal deposits. The geochronological data show that the Cu-Mo deposits in this region are mostly the product of the tectonic-magmatic activities during the Yanshanian. The Yanshanian fine-grained granite and quartz-porphyry are the main metallogenic granitic bodies. The Variscan granodiorite and quartz diorite are the main wall rocks and indicators for prospecting.2.The targets of the Cu-Mo deposit are mostly located to the north of the Haorigalangtu-baiyinbaoligesumu-wulanhuduge N-W fault. The geochemical anomaly is the direct indicator for prospecting. The mineralization occurs in the first member of the Baoligaomiao formation. The geochemical exploration shows obvious anomaly in the Baoligaomiao formation, which makes this formation a indicator for prospecting Cu-Mo deposits in this region. The small-scale annular magnetic amomaly indicates the concealed granite, while the high resistivity indicates the concealed ore body. The silicification, beresitization, biotitization and chloritization are the main alteration types in this region.3.The comprehensive study of the geological characteristics, geophysical-geochemical anomaly and the geochronological data marked2prospecting target areas for Cu-Mo polymetallic deposits. They are Haerdeersi Cu-Mo polymetallic ore prospecting target area, and Wutenggenhuduge Cu-Mo polymetallic ore prospecting target area.