COMPUTING OF TEMPERATURE CORRELATIONS BETWEEN SOIL LAYERS IN RESEARCH WITH SHALLOW BOREHOLES

Abstract

The relevance of the research is caused by the need to study geological objects by direct geophysical measurements of their parameters and applications of the obtained data and the results of mathematical processing for solving environmental management problems. Effective solution of these problems is especially important when research the influence of meteorological parameters on the water-thermal regime of rocks in areas with deep seasonal freezing. The main aim of the research is to develop a geophysical complex to determine the spatial distribution of temperature in the ground, to research the dynamics of changes in this distribution over time, to compute correlation of freezing various soil horizons in the conditions of Siberia and the Far North. Objects of researches are the federal highway «Surgut–Salekhard» within the Yamal-Nenets Autonomous District and the road of territorial importance «Korotchaevo–Urengoy». Methods: methods of analyzing statistical data to research the relationship between the values of variables, including the study of the statistical relationship of two or more random variables (correlation analysis), functional analysis methods for the research of statistical data in the time-frequency range (wavelet transform). Results. It was shown that with an increase in soil depth the freezing pattern is more flat and with increasing distance between observation horizons the correlation between them decreases. In particular, in soil layers 1,9–2,1 m the values of the coefficients of temperature correlation practically do not change at all time scales of the sample. In the soil layers 0,9–1,2 m, 1,2–1,5 m, 1,5–1,8 m on the average time scales of the sample, there is an insignificant change in the coefficients of temperature correlation, and the maximum deviation of the correlation coefficients is observed at large sample time scales. In the soil layers 0,3–2,1 m, 0,3–1,8 m, 0,6–2,1 m on the average time scales of the sample, there is a significant deviation of the coefficients of temperature correlation, and the maximum deviation of the coefficients of temperature correlation is also observed at large scales of the sample. On the basis of the obtained temperature series, spectrograms of wavelet transforms for classical basic wavelets (Morlet wavelet, DOG wavelet, Paul wavelet) were obtained, which indirectly demonstrate the wavelike «promotion» of the cold front (phase) in the ground.

Keywords

• geological environment
• correlation analysis
• environmental management
• wavelet transform
• shallow well method
• geophysical research
• thermal regime of rocks