Abstract: The analogical observation of radon for earthquake prediction has gone through aperiod of 40 years. Earthquake prediction by means of monitoring the changes of the concentration of radon hass of ar achieved good result and has played an important role in short-time earthquake prediction. By the middle 1980', it was gradually recognized that the amount of information and anomaly of escaped radon from self-flowing well was far greater than that of soluble radon. As aresult, the study of micro-dynamic state of theescaped radon was conducted and the automatic radon meter for observing theesca ped radon was developed. During the “Ninth-Five Year Plan”period, the digital radon meter was developed, whose specification of function and technicalperformance has been the best in domestic at present. However, there are different opinions whetherdigital observation of theescaped radon can replace analogical radon observation. By theoretical analysis and study of the earthquake cases throughescaped radon observation, this paper explains the difference and consistency of analogical radon observation and digitalesca ped radon observation, and reaches the conclusion that digital radon observation can com pletely replace analogical radon observation is wells and springs whereescaped radon can bedetected with betterperformance.

Key words: Digital observation, Analogical observation, Escaped radon, Soluble radon