| The study region is located in the area of Kumaling in Changshan County, Zhejiang province. In regional structure, it is located in Huabu-Xindeng fold belt, southwest of Shangfang-Luocun fold system, and west of Bamianshan ore field. The research object is concealed skarn type W,Sn,Mo poly metallic fluorite ore whose formation is related to contact between Yanshanian biotite adamellite and Cambrian limestone. In the 70th-90th of last century, Zhejiang Regional Geology Survey Team, Metallurgic Geological Brigade and the Third Geological Brigade had carried out different scales of regional geological survey and reconnaissance work, preliminary studied the strata, structure and magma features, and found quite a few fluorite and W, Sn polymetallic mineralization exposed on the surface. But there is none further exploration and evaluation of deep metallogenic characteristics because of small scale orebody, low-grade ore and limited technique of preparing. Then the local small enterprises and indigene had largely mined the easily found orebody. In 1998 to 2006 years, Zhejiang Geological Prospecting Institute had conducted fluorite deposit survey and reconnaissance work in research area, and found obvious fluorite and Mo, Sn polymetallic mineralization in drill holes and adits. But there is no meritorious industrial orebody. In 2004 to 2005 years, Henan Geological Prospecting Institute Geophysical institute carried out electrical prospecting work in research area, and delineated three fluorite ore anomaly and one polymetallic anomaly. The later engineering verification (the maximum prospecting depth was 200m) proved that Sn and Po anomaly was obviously, but the grade could not reach industrial requirement. The previous achievements had basically ascertained the strata, structure and magmatic characteristics, and held that Yanqian the granite body, controlled by Yanqian branchy-pitching-anticline, which was spreading in NE-short axis dome structure and pitching in southwest in north of Yanqian village. Based on the inference of the past research that the rock is controlled with the anticline in deep earth, and compared to the research in the past years which is limited to the parts of the surface and shallow, the buried depth of rock mass is gradually increased in NE-SW direction; the contact zones between the rock mass and its country rock where the depth of the rock is shallow and the depositing possibility is less. The research emphasis of this paper is to ascertain the deep interfacial morphology and the depth of the granite body delineate the mineralization anomaly extension and distribution regularity and evaluate resource potential by adopting induced polarization sounding in the plunging crown of anticline.The conditions in research area are complex, such as poor topographic conditions, flourishing vegetation coverage, complex tectonic conditions and kinds of interference factors, and the prospecting effect is not good as low work efficiency by adopting conventional electrical method in complex region deep prospecting. So it is necessary and work premise to find out a fast positioning prediction method that is applicable for complex topography and geology condition. Dual-frequency induced polarization method is appropriate for complex terrain, bad environment and interference regions which is benefited from its advantages such as strong anti-interference ability, light and stability, high observation accuracy. The method which is put forward and bring about by Hejishan academician in 1980s, also is an effective geophysical exploration method and widely used in domestic and overseas geological prospecting and water exploration. So it is adopted in data collecting in the research work. Based on collecting and analyzing the application and development status of induced polarization method at home and abroad, the paper confirms the research purpose and significance, and introduces the dual-frequency induced polarization method in allusion to the complexity of the research area, expounds basic principle and working methods. The feasibility analysis that Dual-frequency induced polarization method applied in research area has be made. We have taken the symmetrical four-pole sounding work by increasing investigation depth, analyzed interference factors met in the data gathering process, gave reasonable precautions and methods to avoid and overcome these interferences. The interior data processing and interpretation is conducted by using computer combine with field records. Finally, we discover and delineate three mineralization abnormals through correctly understand electric sounding curves and knee of curve. Meanwhile, the top depth and changing regularity of granite mass are ascertained, and the drilling verification effect is good. The research work that Dual-frequency induced polarization method applied in Kumaling area has important theoretical and practical significance in later similar area prospecting.
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