Potential use of Radon in Earthquake Predictions

Recently, it was published in the media that Dipak Ghosh, emeritus UGC fellow, who had embedded a solid-state nuclear track detector 70cm underground beside the Faculty Club at Jadavpur University, recorded abnormal fluctuations in radon gas emission from below. This was followed by Earthquakes in Sikkim and other parts of India.

Its worth note that underground Radon concentration has been a subject of study for earthquake prediction. Radon is a radioactive noble gas, which has a half-life of approximately 3.8 days, which means that it can be found only shortly after it has been produced in the radioactive decay chain. For this reason, it has been hypothesized that increases in radon concentration is due to the generation of new cracks underground, which would allow increased ground water circulation, flushing out radon. The generation of new cracks might not unreasonably be assumed to precede major earthquakes. In the 1970s and 1980s, scientific measurements of radon emissions near faults found that earthquakes often occurred with no radon signal, and radon was often detected with no earthquake to follow. It was then dismissed by many as an unreliable indicator. However, as of 2009, it is under investigation as a possible precursor by NASA also.

Ghosh knew what Italian researcher Giampaolo Giuliani had to face when he went a step ahead and predicted the date and time of the earthquake that didn’t come true.He says that its not an easy task but what he gathered from the data is that there is a direct correlation between the soil radon anomaly within 1,000 kilometres from the measuring site, and for intensity above 4 in the Richter scale. They occur 7-15 days before an earthquake with few exceptions.

Research is going on all over the world. Recently Nobel Laureate Georges Charpak has devised a sophisticated detector for radon anomaly as a precursor to earthquake. Radon concentrations are in the air and underground. This is quite normal. We have to collate data from across the country and analyse them over the years before we can predict an earthquake. Unfortunately, not more scientists in India are into this research. (Inputs TOI and Wikipedia)

Month: Current Affairs - November, 2011