Estimation of Amplification due to soil

Amplification due to soil estimated by

  • Amplification recorded on Broad Band Sensor (BBS) for natural earthquakes.
  • Shear wave velocity of soil with depth or soil properties.

Soil properties are measured on borehole samples including N value (Soil Strength) by SPT tests or strength from cone penetration test.

Shear wave velocity is measured by

  • P-S Logging.
  • VS 30 (Shear wave velocity to 30 m depth) by seismic method.
  • Micro tremor array measurements.
  • Liquefaction potential is measured by water depth (>50 m may not liquefy), type of soil (sands,silt and gravel are liquefied) N-value (> 30 m may not liquefy), tri-axial cyclic test of failure of soil samples under simulation of repeated seismic waves.
  • Landslide potential is estimated from slope instability in mountainous area.

Peak Ground Acceleration

Announcement

  • ISR has started geophysical surveys for Geothermal Energy in Gujarat state. ISR has pioneered a technique of 3D MT imaging of crust. Geological faults and crustal structure have been mapped in Kachchh.
  • ISR is carrying out Multiparametric Geophysical and Geochemical studies in Kachchh for earthquake prediction research.
  • ISR has upgraded Gujarat State Seismic Network from 19 online seismic stations to 40.