Abstract: Making use of soil and water radon measurement and soil gamma ray spectrometric measurement, the exploration for favorable prospecting area of thermal underground water in Jiamusi urban area of 50 km² was conducted. Factor analysis was employed to reduce the number of parameters deduced from multiple radiometric methods. The derived principal components f₁, f₂ are undependent with each other and of identified geological means. The trend analysis on f₁ and f₂ was conducted to extract the remainder anomalies which reflect the radioactivity elements enrichment formed by fracture structures and locate the spatial positions of thermal underground water. The results coincided well with the linear structure intersections interpreted by remote sensing, reflecting the effectiveness of radiometric measurements in underground thermal water exploration.

Key words: radiometric measure, radon concentration, γ spectrum, fracture structures, underground thermal water, spatial storage location