The experimental investigation of soil gas radon migration mechanisms and its implication in earthquake forecast
Tóm tắt
Laboratory experiments were performed to help understand the fluctuations and the spike‐like anomalies of Rn in a time series that was recorded continuously at monitoring stations. One of the experiments indicated that Rn is adsorbed on the surface of sand particles and can be liberated with minor changes in the physical conditions of the containing medium. Another experiment indicated that the liberation of ultra‐trace Rn, adsorbed on the surface of sand, was not very sensitive to small temperature and pressure changes but was responsive to the flow of carrier gases. Among the carrier gases tested, CO2 was preferred because it has a boiling point similar to that of Rn. However, all other gases that are inert to Rn can also be carrier gases. Temperature variation in the supra soil layer can be measured fairly accurately inside double‐insulated PVC pipes that also house the Rn detecting system. Temperature variation appears to be related to localized strain heating that is a part of the earthquake energy variation cycle. Up‐flow of soil gas, caused by the strain heating, induced the sudden release of Rn, which thus appears as a spike‐like anomaly. The migration of soil gases is expected to follow the thermal cycle corresponding to each earthquake cycle. Therefore, the spike‐like anomalies can be used, in conjunction with the temperature variation cycle, as time markers to forecast the time, place, and magnitude of a coming earthquake.
Từ khóa
Tài liệu tham khảo
ChengC‐Y HeinickeJ YangTF FuC‐C HongWL TongL‐T(2009)Emission flux of through an active fault zone and estimation of reservoir in SW Taiwan.The 10th International Conference of Gas Geochemistry Volume of Abstracts p. 17.
Chyi LL, 2000, Continuous radon measurements in faults and earthquake precursor and pattern recognition, Western Pacific Earth Science, 1, 227
Chyi LL, 2005, Soil gas radon spectra and earthquake, Terrestrial, Atmospheric and Oceanic Sciences, 16, 763, 10.3319/TAO.2005.16.4.763(GIG)
Chyi LL, 2007, Proceedings of the International Brainstorming Session on Geochemical Precursors for Earthquakes, 38
Chyi LL, 2010, The origin and detection of spike‐like anomalies in soil gas radon time series, Geochemical Journal
Dobrovolsky IP, 2000, Theory of the tectonic earthquake preparation, United Institute of the Physics of the Earth, Russian Academy of Science, 23, 110
Favre JA, 1976, Removal of Radon from Hydrocarbon Streams
Lide DR, 2009, CRC Handbook of Chemistry and Physics
NesmeyanovAN(1974)Radiochemistry. English translation MIR Publishers Moscow p. 643.
Tanner AB, 1980, The Natural Radiation Environment III, 5
Yakovleva VS, 2005, A theoretical method for estimating the characteristics of radon transport in homogeneous soil, Annals of Geophysics, 48, 195
Zhu C, 1982, 1975 Haicheng Earthquake