Monitoring fluorescence of groundwater, mineral and thermal water at distinct wavelengths as potential tool for earthquake precursor research

In previous studies on-line measurements with an on-line flowthrough fluorometer, that was developed for the monitoring of tracer tests in karst areas using fluorescence substances as e.g. uranin, sulforhodamin or naphthionate was used for long term monitoring of fluorescence variations of groundwater and thermal water springs in Switzerland. The variation of the fluorescence intensity of the monitored groundwater yielded some coincidences with occurring earthquakes, depending on their magnitudes, depth and distances from the fluorescence monitoring stations. In this proposed presentation now for the first time a newly developed on line spectrometric instruments for on-line spectral fluorescence analysis dedicated for groundwater quality survey was used for comparison with occurring earthquakes. The quite interesting first results of such a new instrumental approach are shown for the Tamina Spa (Eastern Switzerland). In the conclusion the insights towards earthquake precursor research are discussed with reference to the actual literature.