View More View Less
  • 1 Variable Energy Cyclotron Centre 1/AF Bidhannagar Kolkata 700 064 India
  • | 2 Saha Institute of Nuclear Physics 1/AF Bidhannagar Kolkata 700 064 India
Restricted access

Strong anomalies in the concentration of helium, radon and gamma were observed in gases at the geochemical monitoring station, Bakreswar, West Bengal, India, about two weeks before the 7.9 M earthquake at Sichuan, China. The distance between the epicenter of the earthquake and the monitoring site is about 1800 km. This long distance preseismic observation indicates that the radius of influence of large magnitude earthquakes may be substantially large and may cut across plate boundaries. This paper presents the observed geochemical anomalies for the Sichuan earthquake and discusses empirical postulates between earthquake magnitude and its radius of influence.

  • Das N K, Bhandari R K, Ghose D, Sen P, Sinha B 2005: Curr. Sci. , 89, 1399–1404.

    Sinha B. , '' (2005 ) 89 Curr. Sci. : 1399 -1404.

  • Das N K, Chaudhuri H, Bhandari R K, Ghose D, Sen P, Sinha B 2006: Appl. Rad. Isotope , 64, 144–148.

    Sinha B. , '' (2006 ) 64 Appl. Rad. Isotope : 144 -148.

  • Das N K, Bhandari R K, Ghose D, Sen P, Sinha B 2007: Geochemical precursors for earthquakes. Macmillan, India, 12–21.

  • Dobrovolsky I P, Zubkov S I, Miachkin V I 1979: Pure Appl. Geophys. , 117, 1025–1044.

    Miachkin V. I. , '' (1979 ) 117 Pure Appl. Geophys. : 1025 -1044.

  • Fleischer R L, Mogro-Campero A 1978: J. Geophys. Res. Tech. News Bull. , 83, No. 73, 3539–3549.

    Mogro-Campero A. , '' (1978 ) 83 J. Geophys. Res. Tech. News Bull. : 3539 -3549.

  • Fleischer R L, Mogro-Campero A 1985: Geochim. Cosmochim Acta , 49, 1061–1071.

    Mogro-Campero A. , '' (1985 ) 49 Geochim. Cosmochim Acta : 1061 -1071.

  • Freund F T 2007: Nat. Hazards Earth Syst. Sci. , 7, 535–541.

    Freund F. T. , '' (2007 ) 7 Nat. Hazards Earth Syst. Sci. : 535 -541.

  • Majumdar R K, Majumdar N, Mukherjee A L 2000: J. Appl. Geophys. , 45, 3, 187–202.

    Mukherjee A. L. , '' (2000 ) 45 J. Appl. Geophys. : 187 -202.

  • Morgounov V A, Malzev A 2007: Tectonophysics , 431, 61–72.

    Malzev A. , '' (2007 ) 431 Tectonophysics : 61 -72.

  • Ravi Shankar 1991: J. Geol. Soc. India , 211–220.

  • Rikitake T 1988: Tectonophysics , 148, 195–210.

    Rikitake T. , '' (1988 ) 148 Tectonophysics : 195 -210.

  • Sarkar A N 1982: Tectonophysics , 86, 363–397.

    Sarkar A. N. , '' (1982 ) 86 Tectonophysics : 363 -397.

  • Walia V, Virk H S, Bajwa B S, Sharma N 2003: Radiat. Meas. , 36, 393–396.

    Sharma N. , '' (2003 ) 36 Radiat. Meas. : 393 -396.