A geochemical approach to earthquake reconnaissance at the Baratang mud volcano, Andaman and Nicobar Islands

作者：Chaudhuri Hirok^*; Ghose Debasis; Bhandari Rakesh K; Sen Prasanta; Sinha Bikash

来源：Journal of Asian Earth Sciences, 2012, 46: 52-60.

DOI：10.1016/j.jseaes.2011.10.007

• Geochemical monitoring
• Helium
• Radon
• Mud volcano
• Earthquake

Variations in the relative composition of constituent gases coming out of the mud volcano near Jarwa Creek in Baratang Island, Middle Andaman, are discussed on the basis of regional tectonic settings and seismo-geochemical features. The most abundant gas is CH4 (55.7 vol.%) followed by N-2 (32.2%), O-2 + Ar (9.9%), CO2 (2.0%) and He (0.2%). Concentration of the radioactive gas Rn-222 is relatively high (7500 Bq/m(3)). This paper discusses the experimental methods adopted to continuously monitor He, CH4, CO2 and Rn-222 with a view to identify pre-seismic gas concentration anomalies associated with regional seismic occurrences. Results related to this gas-geochemical monitoring are presented with a purpose to develop ability in ascribing a distinct geochemical anomaly to a particular seismic activity in the region.

• 出版日期2012-3-2