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Recognition of environmentally caused variations in radon time series


Four techniques (pattern recognition, Fourier transformation, cross-correlation, and multiple linear regression) have been used to recognize nontectonic environmental factors affecting groundwater radon data collected by the Caltech automated geochemical network. Several factors, including air temperature, rainfall, water level, carbon dioxide concentration in the water, and barometric pressure, were found to correlate with radon level at some stations in the network. For example, approximately 60% of the variance in radon signal at one site studied (Pacoima) could be accounted for by nontectonic influences. However, it was not possible to correlate all the observed changes in radon concentration with nontectonic environmental variables. Some of the observed radon ‘anomalies’ did appear to be related to either regional changes in tectonic strain or some individual earthquakes. A model is developed to account for spike-like increases in radon caused by carbon dioxide emission.

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  • Callison, J. (1983), private communication.

  • Fleischer, R. L., andMogro-Campero, A. (1978),Mapping of Intergrated Radon for Detection of Long-Distance Migration of Gases Within the Earth: Techniques and Principles, J. Geophys. Res.83, 3539–3549.

    Google Scholar 

  • Fleischer R. L., Hart, H. R. Jr, andMogro-Campero, A. (1980),Radon Emanation Over an Ore Body: Search for Long Distance Transport of Radon. Nucl. Inst. Meth.,173, 169–181.

    Google Scholar 

  • Harrison, J. C., andHerbst, K. (1977),Thermoelastic, Strains and Tilts Revisited. Geophys. Res. Lett.4, 535–537.

    Google Scholar 

  • Hauksson, E. (1981),Radon Content of Groundwater as an Earthquake Precursor: Evaluation of World-wide Data and Physical Basis. J. Geophys. Res.86, 9397–9410.

    Google Scholar 

  • Jiang, F.-L., andLi, G.-R. (1981),The Application of Geochemical Methods in Earthquake Prediction in China. Geophys. Res. Lett.8, 469–472.

    Google Scholar 

  • Klusman, R. W. (1981),Variations in Mercury and Radon at an Aseismic Site. Geophys. Res. Lett.8, 471–464.

    Google Scholar 

  • Klusman, R. W., andWebster, J. D. (1981),Preliminary Analysis of Meteorological and Seasonal Influences on Crustal Gas Emission Relevant to Earthquake Prediction. B.S.S.A.71, 211–222.

    Google Scholar 

  • Melvin, J. D., Shapiro, M. H., andCopping, N. A. (1978),An Automated Radon-Thoron Monitor for Earthquake Prediction Research. Nuclear Instr. Methods153, 239–251.

    Google Scholar 

  • Mendenhall, M. H., Shapiro, M. H., Melvin, J. D., andTombrello, T. A. (1981),Preliminary Spectral Analysis of Near-Real-Time Radon Data. Geophys. Res. Lett.8, 449–452.

    Google Scholar 

  • Shapiro, M. H., et al. (1980),Automated Radon Monitoring at a Hard Rock Site in the Southern California Transverse Ranges. J. Geophys. Res.85, 3058–3064.

    Google Scholar 

  • Shapiro, M. H., et al. (1981),Relationship of the 1979 Southern California Radon Anomaly to a Possible Regional Strain Event. J. Geophys. Res.86, 1725–1730.

    Google Scholar 

  • Shapiro, M. H., et al. (1982).Corrected Radon and CO 2 Variations Near the San Andreas Fault. Geophys. Res. Lett.9, 503–506.

    Google Scholar 

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Shapiro, M.H., Rice, A., Mendenhall, M.H. et al. Recognition of environmentally caused variations in radon time series. PAGEOPH 122, 309–326 (1984).

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Key words

  • Radon anomalies
  • Environmental effects
  • Time series
  • Fourier transform
  • Correlation with environmental factors
  • Earthquakes