GSA Data Repository Item Upper mantle anisotropy beneath the south Indian shield: influenced by ancient and recent Earth processes

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1 Page 1 of 2 GSA Data Repository Item 2146 Upper mantle anisotropy beneath the south Indian shield: influenced by ancient and recent Earth processes V.Pavan Kumar 1, K. S. Prakasam 2, S. S. Rai 3, and Sandeep Gupta 2 1 Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai-4, India. 2 CSIR - National Geophysical Research Institute, Hyderabad 7, India. 3 Indian-Institute of Science Education and Research (IISER), Homi Bhabha Road, Pune-4118, India. LITHOSPHERE, 214 This data set contains the data from 1 seismographs operated between 29 and 211 (Rai et al., 213) and 1 seismographs during (Gupta et al., 23). Operation period for these instruments vary from 6 to 24 months and they are given in Table DR1. To improve the lateral resolution we also include results from 9 stations published from Kumar and Singh (28) and Roy et al. (212). Shear wave splitting measurements have been performed using semi-automated approach of Teanby et al. (24) based on shear wave splitting method of Silver and Chan (1988). The shear wave splitting measurements are given in Table DR2. Detailed statistical analysis of good measurements from 7 stations depicting (i) the delay time t and associated error ( t), and (ii) fast polarization direction and associated error for east Dharwar, west Dharwar and southern Granulite is presented in Figure DR1, Figure DR2 and Figure DR3, respectively. Fast Polarization Direction, and their 2 sigma error bars plotted as a function of backazimuth for all the stations on different geological provinces are shown in Figure DR4, Same figure for delay times are plotted in Figure DR. Figure DR6, represents the Individual null results computed at each seismological station. Due to the 9 uncertainty inherent to the definition of a null, the two potential perpendicular directions of anisotropy are materialized by a cross. REFERENCES CITED Gupta, S., Rai, S.S., Prakasam, K.S., Srinagesh, D., Bansal, B.K., Chadha, R.K., Priestley, K., and Gaur, V.K., 23, The nature of the crust in southern India: Implications for Precambrian crustal evolution: Geophysical Research Letters, v. 3, no. 8, p. 1419, doi:1.129/22gl1677. Kumar, M.R., and Singh, A., 28, Evidence for plate motion related strain in the Indian shield from shear wave splitting measurements: Journal of Geophysical Research, v. 113, p. B836, doi:1.129/27jb128. Rai, S.S., Borah, K., Das, R., Gupta, S., Shalivahan, S., Prakasam, K.S., Sivaram, K., Kumar, S., and Meena, R., 213, The south India precambrian crust and shallow lithospheric mantle: Initial results from the India Deep Earth Imaging Experiment (INDEX): Journal of Earth System Science, v. 122, no. 6, p , doi:1.17/s

2 Roy, S.K., Srinagesh, D., Saikia, D., Singh, A., and Kumar, M.R., 212, Seismic anisotropy beneath the eastern Dharwar craton: Lithosphere, v. 4, p , doi:1.113/l Silver, P.G., and Chan, W.W., 1988, Implications for continental structure and evolution from seismic anisotropy: Nature, v. 33, p , doi:1.138/3334a. Teanby, N.A., Kendall, J.M., and Van Der Baan, M., 24, Automation of shear-wave splitting measurements using cluster analysis: Bulletin of the Seismological Society of America, v. 94, p , doi:1.178/ Page 2 of 2

3 Table DR1: Details of South India broad-band seismograph network stations (Rai et al., 213). Stn. Code Latitude ( o N) Longitude ( o E) Elevation (m) Period of operation East Dharwar Craton MBN /1999 7/2 AMT /29 4/21 ARK /29 9/211 APT /29 8/211 CUP /21 6/21 UKD /29 /211 LTV /1998 /2 PKD /29 /211 KDR /2 6/21 MCR /29 1/211 GBA / /21 BGL /1998 9/2 SLR /29 1/211 VBD /29 1/211 Cuddapah Basin SLM /1998 6/2 TDT /29 8/211 Closepet Granite HPT /29 3/21 HGL /211 8/211 TMK /2 11/21 TGH /29 4/21 Kaladgi Basin BGM /29 8/211 Western Dharwar Craton SUP /29 3/211 BDT /29 1/211 BNR /211 8/211 CRP /21 6/22 GDG /211 8/211 JOG /211 8/211

4 Table DR1. (Continued) HVR /29 3/211 DVR /29 1/211 HYR /29 3/211 TPT /2 12/21 NLR /29 8/211 SKP /29 1/211 HSN /2 12/21 SUL /211 8/211 MYS /21 6/22 GDP /29 4/21 Western Ghats MLN /29 8/211 ANK /211 8/211 MGL /29 8/211 KNR /29 1/211 KZD /21 2/212 Southern Granulite Terrain MTD /29 8/211 CBR /21 /211 MTP /21 6/22 HNR /211 4/212 ATR /211 4/212 YCD /29 2/211 NKL /21 /211 PBR /21 4/212 KKL /29 4/21 UTR /211 4/212 THR /211 4/212 MPR /211 4/212 Madurai Block/Kerala Khondelite Block KOD /21 /211 MVT /211 3/212 ELP /211 3/212 AKT /211 4/212 MVK /211 3/212 TKS /211 3/212 TYD /211 3/212 NGC /211 3/212

5 Table DR1. (Continued) Eastern Ghats MGR /21 8/211 PMR /29 8/211 PDR /29 8/211 PDC /29 1/211

6 Table DR2: Events information (origin time, latitude, longitude, depth), station to event great circle arc length (Distance, in degrees), back azimuth (Baz, in degrees); and results of shear wave splitting measurements from different core-refracted phases at each seismological station. The seismological stations are sorted by geographical locations and/or networks. The quality of the measurements with is rated G (good), F (fair) and N (null). STN Event Event Event Event Distance Baz Phi +/- Error δt +/- Error Phase Quality Lat( o ) Long( o ) Depth East Dharwar Craton MBN / /-.6 SKS G SKS N SKKS N SKS N SKS N / /-.33 SKS F SKS N / /-.2 SKKS G SKS N SKS N / /-.12 SKKS G / /-.7 SKKS G SKS N SKKS N AMT / /-.19 SKS G SKS N / /-.4 SKS F / /-.14 SKKS G / /-.6 SKKS G / /-.33 SKKS F SKS N / /-.42 SKKS F / /-.3 SKKS F / /-.12 PKS G / /-.11 PKS F / /-.14 SKS G / /-.29 SKS G / /-.28 SKKS G / /-.23 SKS G ARK / /-.23 SKKS G / /-.49 SKKS G SKS N / /-.31 SKKS G SKS N / /-.9 SKKS G / /-.18 SKS G / /-.19 SKKS G / /-.4 SKS G SKKS N /-..62+/-.2 SKS G / /-.22 SKKS G SKS N APT / /-.29 SKKS F / /-.36 SKS F / /-.14 SKKS G / /-.39 SKS F

7 Table DR2. (Continued) / /-.1 SKKS G / /-.19 PKS G / /-.11 SKKS G / /-.1 SKS G / /-.9 SKKS G SKS N / /-.21 SKS G /-..8+/-.1 SKKS G / /-.14 SKKS G CUP SKS N SKKS N / /-. SKKS G UKD / /-.6 SKS F SKS N / /-.6 SKS G / /-.4 PKS G / /-.14 SKS G / /-.1 SKS G / /-.19 SKS F / /-.26 SKS G SKKS N LTV / /-.1 SKS F / /-.2 SKS G / /-.24 SKS F SKS N SKS N / /-.23 SKS F / /-.6 SKS F SKKS N SKKS N SKS N / /-.14 SKKS F / /-.16 SKKS G PKD / /-.33 SKS G SKS N / /-.13 SKKS G / /-.23 SKS F SKS N / /-.16 PKS G / /-.17 SKKS G / /-.14 SKS G / /-.34 SKKS G / /-.4 SKS G / /-.14 SKKS F SKS N / /-.1 SKKS G / /-.1 SKS F KDR SKS N SKS N SKS N / /-.9 SKKS G / /-.18 SKKS G

8 Table DR2. (Continued) MCR / /-.18 SKS G / /-.21 SKS G / /-.1 SKS F / /-.46 SKKS G SKS N / /-.77 SKKS G / /-.17 PKS G GBA SKS N SKKS N SKS N SKKS N SKS N SKS N SKKS N SKS N SKS N SKS N SKKS N SKS N SKKS N / /-.1 SKKS G / /-.3 PKS G SKS N / /-.14 SKS G / /-.31 SKKS F SKKS N SKS N BGL / /-.6 SKS F SKS N / /-.7 SKS G SKS N / /-.41 SKS F SKS N SKKS N SKS N / /-.19 SKS F / /-.1 SKKS G SKS N SKS N / /-.11 SKKS G / /-.7 SKKS F SKS N / /-.21 SKKS G / /-.6 SKS F / /-.6 SKKS F SLR / /-.16 SKKS F SKS N / /-.38 SKKS G / /-.16 SKS G / /-.19 SKS G / /-.6 SKKS G / /-.32 SKS G / /-.33 SKS G

9 Table DR2. (Continued) / /-.46 PKS F SKS N VBD / /-.14 SKKS G / /-.11 PKS G / /-.1 SKKS G SKKS N SKS N / /-.6 SKKS G Cuddapah Basin SLM / /-.17 SKS G / /-.8 SKS G SKS N / /-.21 SKS G / /-.4 SKKS G SKS N / /-.2 SKKS G / /-.11 SKKS G / /-.12 SKS F / /-.1 SKS F / /-.9 SKKS G SKKS N /- 8..+/-.7 SKKS G SKS N / /-.1 SKS F TDT / /-.14 SKKS G / /-.17 SKKS G / /-.31 SKS G / /-.29 SKS F / /-.64 SKKS F / /-.33 SKS G / /-.1 SKKS G SKS N / /-.29 SKKS G / /-.7 SKS G / /-.9 SKS F / /-.28 SKS G / /-.14 SKKS G / /-.31 SKKS G Closepet Granite HPT / /-.4 SKS F / /-.18 SKS G / /-.29 SKKS F / /-.31 SKKS G / /-.12 SKKS F / /-.16 SKKS G / /-.9 SKS G HGL / /-.31 SKKS G TMK / /-.14 SKS G /-.7.7+/-.6 SKKS G

10 Table DR2. (Continued) N / /-.31 SKS F TGH / /-.32 SKS G SKS N / /-.2 SKS F / /-.23 SKKS F / /-.2 SKS G / /-.19 SKS G / /-.1 SKKS G / /-. SKS F / /-.13 PKS F / /-.1 SKS G / /-.3 SKS G / /-.19 SKKS F / /-.32 PKS G Kaladgi Basin BGM / /-.26 SKS G / /-.8 SKKS G / /-.7 SKS G / /-.22 SKS G / /-.9 SKS G /-13..+/-.11 SKS G / /-.14 SKKS G / /-.34 SKS F / /-.8 SKS G / /-.34 SKS F / /-.34 SKKS F / /-.14 SKS G / /-.16 SKS G West Dharwar Craton SUP / /-.12 SKKS G / /-.31 SKS F / /-.24 SKS G / /-.47 SKKS G / /-.62 SKKS G / /-.17 PKS F BDT / /-.39 SKS G /-.7.9+/-.2 SKS G / /-.17 SKS G SKS N SKKS N SKS N BNR / /-.21 SKKS G / /-.26 SKS F / /-.33 SKKS G CRP / /-.11 SKS G / /-.33 SKS F SKKS N

11 Table DR2 (Continued) / /-.9 SKS G / /-.41 SKS F GDG / /-.26 SKS F / /-.12 SKS G / /-.12 SKKS G / /-.23 SKS F / /-.44 SKS G / /-.2 SKS G / /-.19 SKKS G JOG / /-.7 SKS G / /-.1 SKKS G SKS N / /-.11 SKKS G HVR / /-.28 SKS G / /-.1 SKS F / /-.9 SKS G / /-.4 SKKS G SKS N DVR /-1..6+/-.11 SKS G / /-.3 SKS F / /-.19 SKS F SKKS N HYR / /-.17 SKS F / /-.16 SKS G / /-.1 SKS F / /-.17 SKS G SKS N / /-.2 SKS G / /-.11 SKKS G / /-.16 SKS G TPT / /-.1 SKS G / /-.41 SKS F SKS N / /-.2 SKS G / /-.7 SKS G SKKS N NLR / /-.9 SKKS G / /-.11 PKS G SKS N SKS N / /-.27 SKKS G / /-.29 SKS F / /-.6 PKS G SKS N / /-.13 SKS G SKS N / /-.17 SKKS G SKP / /-.21 SKKS G

12 Table DR2 (Continued) / /-.33 SKS F / /-.28 SKS F SKS N / /-.26 SKKS F SKS N / /-.23 SKKS G / /-.16 SKS G SKS N / /-. PKS G / /-.16 SKS G HSN SKS N SKS N / /-.36 SKS G SKS N SKS N / /-.8 SKS G SKKS N SKS N SKS N SUL SKS N / /-.47 SKKS G / /-.33 SKS G / /-.26 SKKS G / /-.86 SKS G MYS SKS N SKKS N / /-.42 SKKS G / /-.12 SKS G GDP / /-.9 SKKS G SKKS N / /-.47 SKS G / /-.19 SKS F / /-.31 SKS G SKS N / /-.6 SKKS G / /-.28 SKS F / /-.28 SKS G / /-.18 SKKS F / /-.6 SKS G Western Ghats MLN / /-.12 SKKS G / /-.19 SKKS G / /-.16 SKKS G / /-.14 SKKS G / /-.6 SKKS G ANK / /-.12 SKS F / /-.17 SKS G / /-.1 SKKS G / /-.19 SKKS F

13 Table DR2 (Continued) /-..8+/-.11 SKS G / /-.34 SKKS G / /-.17 SKS G MGL / /-.19 SKS G / /-.2 SKS G /-1.2.+/-.16 SKS G / /-.34 SKS F SKS N / /-.9 SKS G KNR / /-.14 SKS G / /-.23 SKS G / /-.46 SKS F / /-.8 SKS G / /-.46 SKKS G / /-.7 SKS F / /-.26 SKKS G /-.2.8+/-.16 SKS G / /-.98 SKS F KZD SKS N / /-.12 SKKS G / /-.38 SKS G SKS N / /-.9 SKKS G SKS N / /-.26 SKKS G /-1..4+/-.12 SKS G / /-.11 PKS G / /-.24 SKKS G Southern Granulite Terrain MTD /-..82+/-.11 SKS G / /-.26 SKS G / /-.44 SKKS G /-1.2.+/-.11 SKS G / /-.2 SKKS G CBR / /-.16 SKS G SKS N / /-.1 SKKS G / /-.26 SKS G / /-.24 PKS G SKS N / /-.11 SKKS G / /-.6 SKS G SKS N /-1..7+/-.14 SKKS G MTP SKS N SKS N / /-.27 SKS G HNR SKS N / /-.2 SKKS G

14 Table DR2 (Continued) / /-.9 SKS G / /-.17 SKKS F SKS N / /-.29 SKKS G / /-.21 SKS G / /-.9 PKS G / /-.21 SKS F ATR / /-.2 SKS G / /-.2 PKS G / /-.21 SKKS F /-..6+/-.7 PKS G / /-.24 SKS G YCD / /-.31 SKS G / /-.24 SKKS F / /-.34 SKS G / /-.32 SKS F SKS N / /-.1 SKS G / /-.36 SKS G / /-.14 SKKS G / /-.6 SKS F NKL / /-.13 SKS G / /-.7 SKKS G / /-.2 SKS G / /-.8 SKS G / /-.23 SKS G / /-.12 PKS G / /-.6 SKS G / /-.6 SKS G / /-.1 SKKS G SKS N / /-.39 SKKS F / /-.28 SKS G SKKS N PBR / /-.9 SKKS G / /-.23 SKS G SKS N / /-.19 SKKS G / /-.1 SKS G / /-.62 SKS G / /-.2 SKKS G / /-.21 SKS G / /-.6 SKS G / /-.7 SKKS G SKS N / /-.3 SKKS F / /-.33 SKS G / /-.3 SKS G / /-.12 SKS G / /-.28 SKKS G / /-.7 SKS G / /-.16 SKS G / /-.33 SKKS F

15 Table DR2 (Continued) / /-.17 SKS G KKL / /-.33 SKS F / /-.26 SKS F / /-.47 SKS F / /-.1 SKS G / /-.21 SKS G / /-.7 SKS G / /-.22 SKS G / /-.21 SKS G / /-.21 SKS G / /-.6 SKS G / /-.28 SKS G / /-.7 SKS F / /-.21 SKS G SKS N / /-.14 SKS G / /-.28 SKS G / /-.63 SKKS F UTR SKKS N / /-.9 PKS G /- 8..+/-.7 SKKS G / /-.28 SKS G THR / /-.78 SKS G / /-.4 SKKS G /- 7..+/-.7 SKS G / /-.23 SKKS G SKS N / /-.13 SKKS G / /-.2 SKS G / /-.44 PKS G / /-.6 SKS G / /-.4 SKKS G MPR / /-.24 SKS G SKS N SKS N SKKS N / /-.7 PKS G / /-.1 SKS G / /-.24 SKKS G Madurai Block/Kerala Khondelite Block KOD SKS N SKS N SKKS N SKS N SKS N / /-.1 SKKS G / /-.12 SKKS G SKS N / /-.11 SKS G / /-.22 PKS F / /-.1 SKS G

16 Table DR2 (Continued) / /-.33 SKKS G /-.2.+/-.2 SKS G / /-.9 SKKS G SKS N SKS N / /-.11 SKS G MVT / /-.36 SKS G / /-.13 SKKS G SKS N / /-.14 SKKS G / /-.16 PKS G / /-.4 SKKS G ELP / /-.24 PKS G / /-.11 PKS G AKT / /-.1 SKS G / /-.4 SKS G SKKS N /-..62+/-.22 SKS G / /-.7 SKS G SKS N / /-.31 SKKS F / /-.26 PKS G / /-.16 SKS G MVK / /-.17 SKS F / /-.1 SKS G / /-.17 SKKS F TKS / /-.47 SKS G / /-. SKS G / /-.2 SKKS G / /-.11 SKS G SKS N / /-.29 SKKS G SKS N / /-.1 PKS F / /-.12 SKS G TYD SKS N / /-.16 SKS G / /-.1 PKS G / /-.9 PKS G /-..93+/-. SKKS G NGC SKS N / /-.7 SKKS G / /-.3 SKS G / /-.7 SKS G / /-.24 SKKS G SKS N / /-.23 SKS G / /-.34 PKS G / /-.19 SKKS F

17 Table DR2 (Continued) Eastern Ghats MGR SKS N / /-.36 SKKS G / /-.41 SKS F / /-.26 SKKS G / /-.28 SKS G / /-.19 SKKS F / /-.27 SKS G SKS N /-1..7+/-.2 SKS F / /-.29 SKKS G / /-.3 SKS G PKS N / /-.34 SKS G PMR / /-.32 SKKS G / /-.17 SKS G /-1..7+/-.24 SKKS F / /-.18 SKS G / /-.14 SKKS G / /-.3 SKS G /- 9..+/-.16 SKS F / /-.38 SKS G / /-.21 SKKS G / /-.9 SKS G /-1..7+/-.26 SKKS G PDR /-1.7.+/-.24 SKS G / /-.6 SKKS G / /-.6 SKKS G / /-.29 SKKS F / /-.3 SKKS G / /-.14 SKS G SKS N SKS N / /-.4 SKS G / /-.13 SKKS G PDC / /-.11 SKS G / /-.19 SKS G

18 3 3 2 (a) 3 (b) Total Measurements Delay time (s) Error in Delay time (s) 3 2 (c) 2 (d) Total Measurements Fast Polarization ( o ) Error in Fast Polarization ( o ) Figure DR1: Detailed statistical analysis of good measurements from East Dharwar broadband seismic stations depicting (a) the delay time δt and (b) associated error in δt (c) fast polarization direction Φ and (d) associated error in Φ.

19 2 2 (a) (b) 1 1 Total Measurements Delay time (s) Error in Delay time (s) 2 (c) (d) 1 1 Total Measurements Fast Polarization ( o ) Error in Fast Polarization ( o ) Figure DR2: Detailed statistical analysis of good measurements from West Dharwar broadband seismic stations depicting (a) the delay time δt and (b) associated error in δt (c) fast polarization direction Φ and (d) associated error in Φ.

20 3 3 2 (a) 3 (b) Total Measurements Delay time (s) Error in Delay time (s) 3 Total Measurements (c) (d) Fast Polarization ( o ) Error in Fast Polarization ( o ) Figure DR3: Detailed statistical analysis of good measurements from Southern Granulite broadband seismic stations depicting (a) the delay time δt and (b) associated error in δt (c) fast polarization direction Φ and (d) associated error in Φ.

21 9 Cuddapah Basin 9 Closepet Granite φ ( o ) φ ( o ) WDC 9 Kaladgi Basin φ ( o ) φ ( o ) Western Ghats 9 SGT φ ( o ) φ ( o ) Eastern Ghats 9 Madurai/ Kerala Khondelite Block φ ( o ) φ ( o ) Figure DR4: Fast Polarization Direction and their 2 sigma error bars plotted as a function of backazimuth for all the stations on different geological provinces.

22 4 3 Cuddapah Basin 4 3 Closepet Granite δt (sec) 2 1 δt (sec) WDC 4 3 Kaladgi Basin δt (sec) 2 1 δt (sec) Western Ghats 4 3 SGT δt (sec) 2 1 δt (sec) Eastern Ghats 4 3 Madurai/ Kerala Khondelite Block δt (sec) 2 1 δt (sec) Figure DR: Delay times and their 2 sigma error bars plotted as function of backazimuth for all the stations on different geological provinces.

23 GB 17 N DVP BB EDC 16 N KB 1 N CB EGMB CG 14 N WGMB EDC 13 N WDC 7 8 MaB 12 N NoB 11 N 4 NiB 6 SGT 1 N 9 MdB 9 N 1 NUVEL 1A TB 8 N 74 E 7 E 76 E 77 E 78 E 79 E 8 E 81 E Figure DR6: Individual null results computed at each seismological station. Due to the 9 o uncertainty inherent to the definition of a null, the two potential perpendicular directions of anisotropy are materialized by a cross.