Seismo-Geochemical Variations in SW Taiwan: Multi-Parameter Automatic Gas Monitoring Results

Abstract

Gas variations of many mud volcanoes and hot springs distributed along the tectonic sutures in southwestern Taiwan are considered to be sensitive to the earthquake activity. Therefore, a multi-parameter automatic gas station was built on the bank of one of the largest mud-pools at an active fault zone of southwestern Taiwan, for continuous monitoring of CO 2 , CH 4 , N 2 and H 2 O, the major constituents of its bubbling gases. During the year round monitoring from October 2001 to October 2002, the gas composition, especially, CH 4 and CO 2 , of the mud pool showed significant variations. Taking the CO 2 /CH 4 ratio as the main indicator, anomalous variations can be recognized from a few days to a few weeks before earthquakes and correlated well with those with a local magnitude >4.0 and local intensities >2. It is concluded that the gas composition in the area is sensitive to the local crustal stress/ strain and is worthy to conduct real-time monitoring for the seismo-geochemical precursors.

Hydrochemical characteristics of hot spring waters in the Kangding district related to the Lushan <i>M</i><sub>S</sub> = 7.0 earthquake in Sichuan, China

“…The short-term hydrogeochemical precursors for earthquakes (King et al, 1995;Favara et al, 2001;Quattrocchi et al, 2003;Du et al, 2008;Dadomo et al, 2009), the co-seismic response of hydrochemistry Yang et al, 2006;Reddy et al, 2011) and post-seismic geochemical changes in hot springs have been observed throughout the world (Thomas, 1988;Woith et al, 2013;Italiano et al, 2010;Zhou et al, 2010;Malakootian and Nouri, 2010;İnan et al, 2012). Claesson et al (2004) observed changes in multicomponent constituents and δ 18 O of groundwater due to a seismic event (M = 5.1) in northern Iceland.…”

Continuous, Direct Gas-Geochemical Monitoring in Hydrothermal Vents: Installation and Long-Term Operation on Nisyros Island (Greece)

“…They also review other papers describing the application of gas-monitoring equipment. Recently an automatically operated monitoring system based on a quadrupole mass spectrometer for the surveillance of seismic and geochemical variations on mud volcanoes in southwest Taiwan was described by YANG et al (2006).…”

Soil-gas radon/helium surveys in some neotectonic areas of NW Himalayan foothills, India

“…Correspondence to: V. Walia (vivekwalia@rediffmail.com) gases like radon ( 222 Rn) and helium ( 4 He) are widely applied in studies to locate buried/blind faults and in seismic monitoring activities (Yang et al, , 2006. Both radon and helium are products of the uranium decay series.…”