| As the result of certain geological anomalous process, deposit is located at the area where the spatio-temporal coincidence of a series of geological anomalies. The aim of geological anomaly research is to reveal the mineral deposit controlling factors and indictor, and the key of quantitative mineral resources assessment based on geological anomaly is researching the geoanomaly associated with mineralization. Therefor, how to recognize the conceal geoanomaly information associated with mineralization effectively is becoming the difficulty and the key point of geological anomaly research. Meanwhile, quantitative mineral resources assessment based on geological anomaly is the theory in sequence and emphasized on quantitative extraction of geoanomaly information associated with mineralization. In mineral resources prediction process, how to identify the relationship between multi-scale and multi-type geoanomaly associated with mineralization and different stage of ore-finding process is the basic of quantitative mineral resources assessment based on geological anomaly, the precondition of ore-finding and the evidence of target selection.This study is based on the geological anomaly ore-forming theory, using different information processing techniques to obtain geoanomaly information associated with mineralization in different level, specially focus on researching and applying multi-statistical analysis, geostatistics, multi spectrum and area filtering (S-A) technique, and Bidimensional empirical mode decomposition (BEMD) method on extracting the conceal geoanomaly information associated with mineralization, then, explore application of the telescoping ore targets at multiple scales base on geological anomaly. The studied results show as follows.1. Eastern Yunnan area-the important Cu-Au-PGE ore-forming perspective area in China is selected as the study area. The factor analysis, geostatistical and multifractal S-A filtering method are applied to quantitatively extract and estimate the Pt-Cu-Au mineralization anomalies from the complicated geological background. The research shows that: (1) The results of factor analysis illustrate that there are three element associations existing in Eastern Yunnan area; (2) The semivariation analysis illustrates that the concentrations of Pt, Cu and Au are continuous in NE trend (9°~18.6°) and the maximal ranges are about 95km. The geochemical maps obtained by the Universal Kringing imply the concentration distributions of Pt, Cu and Au are mainly controlled by the faults and magmatism; (3) The multifractal S-A filtering method characterizes the detailed information of local mineralization, extract the conceal mineralization information.2. A bidimensional empirical mode decomposition (BEMD) program on a MATLAB platform was effectively used to handle gravity signals for the Tongshi gold field. This yielded a three-dimensional intrinsic mode function image that meticulously depicts the spatial distribution relationship between various gold deposits and the different geological units of the gold field rather than Fourier transform. By combining the IMF image with geological features yields a geological–geophysical pattern for the Tongshi gold field showing the formation and distribution of gold deposits, which shows that concealed gold deposits might be discovered on the northeastern side of the Tongshi intrusive complex and the contact metasomatic zone covered by early Cretaceous volcanic sedimentary rocks.3. Different geological and ore-forming problems can be solved by different geomathematic methods. The linear geomathematic methods such as the factor analysis and geostatistics can be used to explore the regional ore-forming background and the regional spatial variability of the ore-forming elements and the element associations, while the nonlinear geomathematic methods such as S-A method are efficient in extracting the local ore-forming information and the BEMD method are efficient in decomposing the complex superimposed field singles such as gravity data into several components to obtain the geoanomaly information associated with mineralization under cover. These methods are of benefit to the concealed ore-forming anomaly information extraction.4. Following the method of quantitative delineation of"5P"ore finding area, the Pt-Pd geochemical province in Eastern Yunnan was defined as permissive ore-finding area for Pt and the telescoping ore targets at multiple scales was applied in this area. The semi-variograms were used to quantitatively describe the variability of Pt anomalies and further analyze the factors controlling the variability, preferable ore-finding area and potential mineral resource area were quantitatively delineated based on multi-scale exploration data. During the process of telescoping ore targets, multi level of ore-control factors were revealed while the amount of geoanomaly information gradually increased, the target areas gradually decreased while the Pt resource amount concentrated singularly. So, the telescoping ore targets at multiple scales has a good exploration function that efficiently focuses on ore targets and easily and quick to apply, especially in the green field exploration.
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