Correlativity between short-term change of fault gas radon concentration and air temperature & atmospheric pressure

Using daily values of gas radon concentration from Jiayuguan fault as well as daily values of air temperature and atmospheric pressure in Jiayuguan, this paper studied the influence of air temperature and atmospheric pressure on short-term change of gas radon concentration by calculating the correlation coefficient between air temperature & atmospheric pressure and gas radon concentration. The results showed that both air temperature and atmospheric pressure had obvious influence on short-term change of gas radon concentration. ① The influence from atmospheric pressure is more remarkable than that from air temperature. ② The influences of air temperature and atmospheric pressure both had time-lag characteristic. At 0—8 o’clock, their influences on radon concentration were gradually weakened. The influence of air temperature was the weakest at 7 and 8 o’clock in a day, but the influence of atmospheric pressure was the weakest only at 8 o’clock in a day. At 9 o’clock, their influences were rapidly increasing. Since then, the influence of atmospheric pressure became slower growth and it was up to the strongest at 18 o’clock in a day, but the influence of air temperature became slow down. ③ There were significant differences in influences of air temperature and atmospheric pressure in different months. The influence of atmospheric pressure had good laws such as it was on high level state from January to April and started to decline from May and reached the lowest in August, and then, it rose and reached highest level in October, and it was at a high level. The influence of air temperature had no obvious laws and their monthly frequency values were all low. ④ The analyses on related earthquakes indicated that the short-term sharp changes of gas radon concentration had no ability to forecast earthquake.