Abstract: In this paper, according to the spatial auto-correlation characteristics of radiation field, the general Kriging method in geo-statistical spatial interpolation combined with logarithmic transformation is used to reconstruct the radiation field under the condition of unknown radioactive source. The method is tested through two measured radiation field data sets. The results show that when the Exponential model or Spherical model is selected for semi-variance fitting and the measuring points are selected randomly, the mean deviation of the of the reconstructed result ranges from 21.51% to 74.01%, which proves that the method is effective and feasible in practical application. In addition, the relationship between the distribution of measuring points and the accuracy of reconstructed radiation field is preliminarily analyzed and studied, and the selection scheme that the distribution of measuring points should be as uniform as possible is determined.

Key words: 3D radiation field, Geo-statistical interpolation, Kriging method