Earthquake Source Parameters and Micro-tremor Site Characteristics Study-Geochemical Monitoring

Earthquake Source Parameters and Micro-tremor Site Characteristics Study-Geochemical Monitoring

The study of active faults and earthquake precursory provides a basis for anticipating of future earthquakes and related phenomena such as surface faulting, and other geological/tectonic features. Taiwan is product of ongoing collision of Eurasian plate with Philippine Sea plate. The ongoing collision between the different plates makes Taiwan and highly active tectonically and intensively faulted. The present work is focused on Hsincheng fault in Hsinchu area and the Hsinhua fault in Tainan for earthquake monitoring using soil-gas method to determine the influence of such formations on enhanced concentrations of different gases in soil to monitor the tectonic activity in the region, along with some weekly monitoring results for the establishment of monitoring station at Jiaosi in Ilan area. To carry out the present investigation variation in temporal soil-gases compositions was measured at established continuous earthquake monitoring stations along the above said faults. Observations have shown potential precursory signals for some major earthquakes in the region. Previous year’s results have shown that Hsinhua and Hsincheng faults have different tectonic settings and a tectonic based physical model was proposed. Based on the anomalous signatures from monitoring stations we are in a state to identify the area for impending earthquakes and we have tested it for some major earthquakes which rocked the whole Taiwan in recent times.