Abstract:

The paper first attempts to use blind source separation technique for geochemical field, and uses FastICA algorithm in the theory of blind source separation for the study of ore-forming anomaly identification of 1∶10,000 soil geochemical survey data in Dong Gapu copper exploration area,Tibet. First, we established the anti-combination model of the evolution of geochemical data elements based on blind source separation algorithm in order to determine the geochemistry of combined ore-forming elements. Then, we determined the single-element geochemical anomalies and elemental composition of the lower limit, the delineation of abnormal concentration centers using fractal method, and determine the abnormal zonation. Finally, we combined the elemental characteristics of the study area with geological features, compare  single-element anomaly map and the combination of anomaly, and explain the anomaly classification and anomaly evaluation of geochemical elements of the study area. Division of four anomalous areas in the latter part of the validation project achieved good results.

Key words: geochemical anomaly, blind source separation, fractal, content-area method, content-grads method, Dong Gapu copper exploration area, Tibet