Electronic Supplement to
Stress-Drop Variations and Source-Scaling Relations of Moderate Earthquakes of the Indian Tectonic Plate

by Bandana Baruah, Prakash Kumar, M. Ravi Kumar, and Shib S. Ganguli

This electronic supplement contains most of the individual station data that comprise a list of events and associated estimated parameters which are used in the main article and plots consisting of both frequency-independent and frequency-dependent analyses, along with a singular value plot for inversion.


Table

Table S1. List of the events used and the values of estimated parameters in our present analysis.


Figures

Figure S1. Variations of estimated seismic moment (M0, solid gray circle) and corner frequency (fc, open circle) with different chosen window lengths (in seconds) of the waveform to compute the spectrum for the station NGP (located in the central part of India). The estimated values are smoothed and shown as black lines. The shaded region shows the window length where the estimated parameters are fairly constant.

Figure S2. Example of the spectral fitting using the grid-search method for the station indicated as inset. Rightmost panel: the zig-zag black and gray lines are the observed spectra for P and S waves with their best-fitted curves shown by solid black and gray curves for the best search of moment and corner frequency shown in subplots in the left and middle panels, respectively. The thick black and gray dashed curves are the best fitting for the frequency-dependent attenuation factors (Q0 and η) with optimal solutions shown in subplot in the middle panel. The waveforms with P and S phases are also shown as black and gray wiggles. The time windows around P and S phases used for the present analysis are shown as gray-shaded areas. The contours show the optimal estimates of the parameters.

Figure S3. Same as Figure S2.

Figure S4. Same as Figure S2.

Figure S5. Same as Figure S2.

Figure S6. Same as Figure S2.

Figure S7. Same as Figure S2.

Figure S8. Same as Figure S2.

Figure S9. Same as Figure S2.

Figure S10. Same as Figure S2.

Figure S11. Same as Figure S2.

Figure S12. Same as Figure S2.

Figure S13. Same as Figure S2.

Figure S14. Same as Figure S2.

Figure S15. Same as Figure S2.

Figure S16. Same as Figure S2.

Figure S17. Same as Figure S2.

Figure S18. Same as Figure S2.

Figure S19. Same as Figure S2.

Figure S20. Same as Figure S2.

Figure S21. Same as Figure S2.

Figure S22. Same as Figure S2.

Figure S23. Same as Figure S2.

Figure S24. Same as Figure S2.

Figure S25. Same as Figure S2.

Figure S26. Same as Figure S2.

Figure S27. Same as Figure S2.

Figure S28. Same as Figure S2.

Figure S29. Same as Figure S2.

Figure S30. Same as Figure S2.

Figure S31. Same as Figure S2.

Figure S32. Same as Figure S2.

Figure S33. Same as Figure S2.

Figure S34. Same as Figure S2.

Figure S35. Same as Figure S2.

Figure S36. Same as Figure S2.

Figure S37. Same as Figure S2.

Figure S38. Same as Figure S2.

Figure S39. Same as Figure S2.

Figure S40. Same as Figure S2.

Figure S41. Same as Figure S2.

Figure S42. Same as Figure S2.

Figure S43. Same as Figure S2.

Figure S44. Same as Figure S2.

Figure S45. Same as Figure S2.

Figure S46. Same as Figure S2.

Figure S47. Same as Figure S2.

Figure S48. Same as Figure S2.

Figure S49. Same as Figure S2.

Figure S50. Same as Figure S2.

Figure S51. Same as Figure S2.

Figure S52. Example of the spectral fitting using the grid-search method for the station AJMR similar to Figure S9, but the grid search has been performed for the corner frequency versus frequency-independent attenuation parameter as shown in the subplots for P and S waves, respectively, for known M0 (from Global Centroid Moment Tensor [CMT] catalog).

Figure S53. Same as Figure S52.

Figure S54. Same as Figure S52.

Figure S55. Same as Figure S52.

Figure S56. Same as Figure S52.

Figure S57. Same as Figure S52.

Figure S58. Same as Figure S52.

Figure S59. Same as Figure S52.

Figure S60. Same as Figure S52.

Figure S61. Same as Figure S52.

Figure S62. Same as Figure S52.

Figure S63. Same as Figure S52.

Figure S64. Same as Figure S52.

Figure S65. Same as Figure S52.

Figure S66. Same as Figure S52.

Figure S67. Same as Figure S52.

Figure S68. Same as Figure S52.

Figure S69. Same as Figure S52.

Figure S70. Same as Figure S52.

Figure S71. Same as Figure S52.

Figure S72. Same as Figure S52.

Figure S73. Same as Figure S52.

Figure S74. Same as Figure S52.

Figure S75. Same as Figure S52.

Figure S76. Same as Figure S52.

Figure S77. Same as Figure S52.

Figure S78. Same as Figure S52.

Figure S79. Same as Figure S52.

Figure S80. Same as Figure S52.

Figure S81. Same as Figure S52.

Figure S82. Same as Figure S52.

Figure S83. Same as Figure S52.

Figure S84. Same as Figure S52.

Figure S85. Same as Figure S52.

Figure S86. Same as Figure S52.

Figure S87. Same as Figure S52.

Figure S88. Same as Figure S52.

Figure S89. Same as Figure S52.

Figure S90. Same as Figure S52.

Figure S91. Same as Figure S52.

Figure S92. Same as Figure S52.

Figure S93. Same as Figure S52.

Figure S94. Same as Figure S52.

Figure S95. Same as Figure S52.

Figure S96. Same as Figure S52.

Figure S97. Same as Figure S52.

Figure S98. Same as Figure S52.

Figure S99. Same as Figure S52.

Figure S100. Same as Figure S52.

Figure S101. Plot showing the size of the singular value against their index number. The shaded region shows the value of p = 3 taken for inverting the matrix.


Data and Resources

The focal mechanism and seismicity data used in this study are taken from Global Centroid Moment Tensor (Global CMT) catalog (http://www.globalcmt.org/CMTsearch.html, last accessed December 2013).


References

Chopra, S., D. Kumar, and B. K. Rastogi (2011). Attenuation of high frequency P and S waves in the Gujarat region, India, Pure Appl. Geophys. 168, no. 5, 797–813.

Gupta, S. C., V. N. Singh, and A. Kumar (1995). Attenuation of coda waves in the Garhwal Himalaya, India, Phys. Earth Planet. In. 87, 3–4.

Hazarika, P., M. R. Kumar, and D. Kumar (2013). Attenuation character of seismic waves in Sikkim Himalaya, Geophys. J. Int. 195, no. 1, 544–557, doi: 10.1093/gji/ggt241.

Joshi, A. (2006). Use of acceleration spectra for determining the frequency-dependent attenuation coefficient and source parameters, Bull. Seismol. Soc. Am. 96, 2165–2180.

Kumar, N., I. A. Parvez, and H. S. Virk (2005). Estimation of coda wave attenuation for NW Himalayan region using local earthquakes, Phys. Earth Planet. In. 151, nos. 3/4, 243–258.

Mohanty, W. K., R. Prakash, G. Suresh, A. K. Shukla, M. Y. Walling, and J. P. Srivastava (2012). Estimation of coda wave attenuation for the national capital region, Delhi, India using local earthquakes, Pure Appl. Geophys. 166, no. 3, 429–449.

Parvez, I. A., P. Yadav, and K. Nagaraj (2012). Attenuation of P, S and coda waves in the NW-Himalayas, India, Int. J. Geosci. 3, no. 1, 179.

Paul, A., S. C. Gupta, and C. Pant (2012). Coda Q estimates for Kumaun Himalaya, Proc. Indian Acad. Sci. (Earth planet. Sci.) 112, 569–576.

Sharma, B., P. Chingtham, A. K. Sutar, S. Chopra, and H. P. Shukla (2015). Frequency dependent attenuation of seismic waves for Delhi and surrounding area, India, Ann. Geophys. 58, no. 2, S0216.

Singh, C., S. K. Basha, M. Shekar, and R. K. Chadha (2012). Spatial variation of coda wave attenuation in the southern Indian shield and its implications, Geol. Acta 10, 309–318, doi: 10.1344/105.000001751.

Singh, C., A. Singh, V. S. Bharathi, A. R. Bansal, and R. K. Chadha (2012). Frequency-dependent body wave attenuation characteristics in the Kumaun Himalaya, Tectonophysics 524, 37–42.

[ Back ]