Metallogenic Characteristics And Comprehensive Information Prediction Of Fe And Au Deposits In Jiantang Area, Heilongjiang Province

Survey region located in the eastern part of Heilongjiang province and the southeast edge of Jiangsu massif, it with Songnen massif adjacent is bounded in Mudanjiang Fault, which belongs to Shuangyashan-Boli sub-metallogenic belts of Jiamusi-Xingkai metallogenic belt. It is a good geological background of Fe, Au and W mineralization. The study area has the lower lever of prospecting and exploration and it has a great prospecting potential. Analysis and study 4 the typical deposits in the area to extract the ore-prospecting criteria and summarizes metallogenic characteristics of Au and Fe deposts. Based on analyzing and researching 1:50 000 the existing information prospecting of the geological, geophysical, geochemical, remote sensing and mineral, we mark out metallogenic prospect areas. It is evaluated by ore-prospecting potential of metallogenic prospect and select the favorable metallogenic prospective area, to indicate the direction of the prospecting work in the future.The strata exposed in the region are mainly Dapandao group and Jiantang group of Xingdong rock group in Neoproterozoic; Chengzihe group, Muling group, Dongshan group and Houshigou group of Cretaceous in Mesozoic; Fujin group and Chuandishan group of Neogene of Cainozoic; Quaternary sediments. The intrusive rock in the region are mainly Xibeileng diamictite of paleoproterozoic era; Granodiorite, Syenogranite, Alkali-feldspar granite and Monzonitic granite of Middle-late Permian. It is favorable metallogenic area near the contact zone of.the acidic intrusive rock of Middle-late and Xingdong group. It is derived from Xingdong group that are Au and Fe. Part of the Au comes from the magma of the same period with the ore-forming hydrothermal. The NE and NW fault trending are the major structure as passageway and host for ore fluid.The zircon U-Pb dating of metallogenic rockbody show that the mineralization for sedimentary and metamorphic stages of iron mine have formation in the late Proterozoic era to late Cambrian period(655±1.3~486±13 Ma). The deposit of hydrothermal ore has two stages: first, the migmatization formed a large area of mixed granite in the Cambrian period(481±10 Ma); second, there was happened large-scale magmatism in late Hercynian(267.1±1.8 Ma) to early Indosinian(227.8±4.0 Ma). Two stages of the magmatic activity provide plenty of hydrothermal origin for mineralize. The wall rock alteration of hydrothermal(skarn) type deposit is mainly composed of containing hydroxyl minerals, such as silicification, sericitization, chloritization, carbonatization, kaolinization, skarn lithification. The deposit of metallogenetic element derived from Xingdong group has a lot of magnetite. The place occurred orebody show higher magnetic anomaly.The margin of gravity uplift is favorable metallogenic area. Aeromagnetic anomalies are mainly divided into three types, deciphering 12 th ring structures and 90 th fracture structure of different size. SN trending structure is the basic framework in the area, NE and NW trending faults well development. Aeromagnetic anomaly area of higher values is important area to looking for sedimentary-metamorphic iron ore and the edge of ring structures is favourable metallogenic area for hydrothermal type. Iron alteration and hydroxy corrosion of remote sensing interpretation mainly locate in the west of survey region. The data statistics of 1: 50000 stream sediment shows that Au-Ag-As-Sb have obvious associated relations. There are 21 single-element anomalous of Au, 4 single-element anomalous of Fe and 7 combination element anomaly contain Au. Metallogenic element anomalies are mainly distributed near the contact zone of intrusive rock in middle-late Permian and Xingdong group.Combined with geology, geophysical, geochemical exploration, remote sensing and mineral information in Jiantang area, we selecte 4 metallogenic prospection: including 2 I grade(Class A) metallogenic prospection area, 1 Ⅱ grade(Class B) metallogenic prospection area and 1 III grade(class C) metallogenic prospection area. Finally, we optimization select the 3 area for ore prospecting target area by evaluation of prospective area for ore prospecting potential.