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located by analyzing arrival times of P and S wave phases. Further these locations were improved by HYPODD relocation program. Intense micro tremor activity (M≤3.5) is confined and clustered around Kopili lineament. More than 97% of the seismicity is observed in the form of micro tremor activity. Very few M 4.0-‐5.0 earthquakes observed during this period. Two clear segments of Kopili lineament is seen, through clear concentration of seismicity along these segments. Depth distribution of the seismicity distribution suggests that the lineament is dipping towards east-‐southeast with the deepest seismicity in the Kopili lineament extends up to a depth of 50 km indicating the seismicity extends into the mantle. Frequency magnitude analysis reveals ‘b’ value of 0.71 for this region. A high value of P-‐wave average velocity of 6.71 km/s and low b value of 0.71 probably indicates the region is under high stress. S1-P2 Seismicity of Gujarat state, Western India. Santosh Kumar*, Sandeep Kumar Aggrawal and B.K. Rastogi, Institute of Seismological Research, Gandhinagar- 382 009, India *Corresponding author email: sundriyal007@gmail.com Physiographically Gujarat state can be divided into three parts– Kachchh, Saurashtra and Mainland. Since 1970, seismicity in Gujarat was monitored with several analogue seismographs in the mainland and at Bhuj and this network has not missed any earthquake of M>3 in Gujarat in last four decades. In 1980s only one or two digital seismic station were operating in Gujarat. From mid 2006 a dense network has been installed by ISR which currently has 50 broadband seismographs and 48 accelerographs in Gujarat state. 36 stations are connected via VSAT to ISR data center which works round the clock. The detectibility is M2.0 in Kachchh active area and M2.5 in other areas. The Kachchh region is considered seismically one of the most active intraplate regions of the World. It was known to have high hazard but low seismicity in view of the occurrence of several large earthquakes but fewer moderate or smaller shocks. After 2001 Bhuj earthquake of 7.7, seismicity defused for some time, but there was a spurt of increased activity for the two years in 2005 and 2006. During this period the activity spread around the aftershock zone and to nearby faults such as to the Wagad area towards East and Gedi fault to the NE. Subsequently it further spread to Allah Bund and Island Belt in the North. Seismicity has increased several fold in Kachchh after the Bhuj (23.44 0 N 70.31 0 E) earthquake of Mw7.6
The main shock and most of the aftershocks occurred along a south dipping (~45 o ) hidden fault from 10 to 40 km depth. In Saurashtra many districts showed the seismic activity prominently Jamnagar, Junagarh, Rajkot, Surendernagar, Bhavnagar and Porbandhar. Near Lalpur about 200 shocks were felt with blast like sound in 2006 and 2007. The maximum magnitude was 4.0 on September 30, 2006. Talala region in Junagarh district was rocked with 2 earthquakes of M 4.8 and M5.0 on 6 th Nov. 2007 and in 2011 earthquake of M5.0 occurred in Talala, on 20 th Oct. 2011. The main shock and most of the aftershocks occurred up to 10-15 km depth. In mainland Gujarat shock of M.4.4 occurred on 2 nd September 2010 near Patan on Cambay rift and lies in east of Kachchh rift. There is no historical earthquake reported nearby the epicenter of current earthquake and this may be a sign of further spreading of Kachchh seismicity. A shock of M3.2 occurred near Mehsana on 30 th March 2010 and other shock of M3.5 occurred on May 20 th , 2008 in Surat. Some microshocks occurred west of Godhra and 50 km east of Gandhinagar also in period 2001-2010. We have prepared a catalogue of Gujarat seismicity since 1668 to 2011 and the adjoining region bound by 20 0 –25.5 0 N and 68 0 –75 0 E with the help of all available earthquake catalogues (historical and recent) pertaining to the region. Historical earthquakes of this region before 1900 were taken from the catalogue prepared by Oldham (1883). The catalogues prepared by Tandon and Srivastava (1974), Chandra (1977) Srivastava and Ramachandran (1985), Ramachandran and Srivastava (1991), Srivastava and Rao (1997), and Malik et al. (1999) for this region has been also used. The sources of modern seismicity database are India Meteorological Department (IMD); Geological Survey of India (GSI); NEIC-USGS; International Seismological Centre (ISC); Gujarat Engineering Research Institute (GERI), National Geophysical Research Institute (NGRI) and Institute of Seismological Research (ISR). Aftershocks have been removed from the whole catalogue. Stochastic analysis of earthquakes of Gujarat region using Weibull, Gamma and Lognormal models indicated recurrence intervals of earthquake of M ≥ 5.0 in Saurashtra, Mainland Gujarat and Kachchh as 40, 20 and 13 years, respectively (Yadav et al. 2008). S2: Recent Intraplate Earthquakes: Source Parameters and Effects
Page 1 and 2: INDO-US WORKSHOP ON “INTRAPLATE S
Page 3 and 4: IUSSTF solicits proposals for its a
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Page 15 and 16: not been a significant earthquake i
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Page 49 and 50: Kanter, 1990). The recent 2001 Bhuj

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indoâ€“us workshop on â€œintraplate seismicityâ€ - The CERI Blog