APPENDIX - I. Appendices E 76'39'15"

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1 APPENDICES

2 APPENDIX - I Table showing the name, type and location for different samples collected fiom Hutti, Kolar and Ramagiri areas. The samples HMBl to HMB13, HAVI, HAV2 and H-I, H-2, H-3, H-5, EI-7 and H-9 were collected from Hutti area and the latitude and longitude of the sample locations are obtained from GPS (Model: Gamin GPS-12). Samples L-1, L-3 and K-1 to K-5 were collected from Kolar area and samples R-1, R- 3, R-4 and R-5 were collected from Ramagiri area. Latitude and longitude of the sample locations are inferred from the Survey of India topographic sheets 57W8, 57Ll1 and 57Ll5 for Kolar samples and 57Fl7 and 57Fl11 for Ramagiri samples. Sample I Sample Type 1 Location 1 Latitude / Longitude 1 HMB 1 HMB 2 HMB 3 HMB 4 HMB 5 NMB 6 Medium grained Amphibolite Coarse grained Amphibolite Fine grained Amphibolite Coarse grained Metabasalt Medium grained Metabasalt Fine grained Metabasalt KMB 7 / Coarse grained Metabasalt I Madrainakota River Bed I N 16O14'24" / E 76'38'16" BMB 8 1 Chlorite Carbonate Schist / East of Maski 1 N 15O58'29" 1 E 76039'51N HMB10 1 Chlorite Carbonate Schist HMB 11 I Talc-Tremolite Actinolite Schist South of Chinchargi South of Chinchargi - South of Chincharei East of Chinchargi East of Uti-Palkanmardi Road Madrainakota River Bed West of Pamankallur West of Pamankallur N 16'1 1'47" N 16'1 1'46" N 16'1 1'53" N 16O12'04" N 16O14'57" N 16O14'24" N 16'06'12" N 16'06'13" E 76'47'03" 1 E 76O47'04" E 76O47'06" E 76'47'42" E 76 47'201' E 76'38'15" E 76'39'59" E 76'39'15" 1 HMB13 I Chlorite Carbonate Schist 1 Southwest of Gaialagatta 1 N 16 06'42" / E 76'40'04" / I HAV 1 I Felsic Volcanic I East of Gaialaaatta / N 16O08'13" / E 76'40'56" 1 / HAV 2 1 Felsic Volcanic I Southeast of Uti / N16O15'47" / E76'46'45" / / H-1 / Granodiorite I North of Golapalli 1 N 16'19'54" 1 E 76O39'19" 1 H-3 / Granodiorite I Southeast of Kardikal / N 16O09'24" 1 E 76O29'54" H-3 I Granite I East of Kasamdoddi /N16O11'26" /E76051'51fl

3 Sample equivalents in the present work for the samples considered for plotting REE patterns of Hutti metatholeiites by Giritharan and Rajamani, (1998) (Fig. 2.3a). Giritharan and

4 APPENDIX - II Counts The X-Ray Diffractograms stacked below are for a) the metabasalts of the E-W arm of the Hutti Schist Belt and b) the metabasalts of the N-S arm of the Hutti Schist Belt. The measurements were recorded using a step size of 0.02" 28 and a scan speed of 2.4" 28lmin and scanned from 10" to 75" 20. The Cu K, wavelength for the X-Ray generated was 1.54A. The E-W arm rnetabasalts are found to be predominated by magnesiohomblende, quartz. labradorite and clinochlore, while the N-S arm metabasalts are found to be predominated by clinochlore, quartz, calcite and albite. The y-axis scale corresponds to the samples HMB-1 and HMB-8 only for Fig. a and b, respectively Mh Mh - Magnesiohornblende a ~h Q - Quartz L - Labradorite CI - Clinochlore CI - Clinochlore Position ["2Theta]

5 APPENDIX Concentrations of Calibrating Solutions used for the determination of Tracer Solution Concentrations: Johnson Matthev Rb metal (99.75% ~ure): Concentration of Rb in the calibrating solution = pglg. Johnson Matthev Nd metal (powder-fonn. 99.9% pure): Concentration of Nd in the calibrating solution = pgg. Johnson Matthev Sm metal (~owder form, 99.9%,mre): Concentration of Nd in the calibrating solution = pg/g. K-Feldspar solzltion (provided bv Prof Klaus Mezaer. University ofmuenster. Germanv): Concentration of Rb = pglg. Concentration of Sr = pglg. " ~ r / = ~ ~ ~ r Ames Snz and Nci metal (provided bv Prof Klaus Mezaer, Universitv of Muenster, Germanv): Concentration of Sm in Sm-Nd Mixed calibration solution = 9.77 pg/g. Concentration of Nd in Sm-Nd Mixed calibration solution = pg/g. SRM987 standard for Sr: Concentration of Sr in SRM987 calibrating solution = 200 pglg. Abundances of isotopes in the tracer solutions: Rubidium - " ~ = b 98.1 %; S5~b = 1.9 % Strontium - 84~r = 68.1 %; s6~r = 6.7 %; 87~r = 2.9 %; *'~r = 22.3 % Samarium - '44~rn= %; 147~m = %; 14'sm = %; I4%m = %; 150sm = %; '52~rn = 98.9 %; 154~rn = 0.58 % Neodymium- 14*~d = 0.42 %; 143~d = 0.25 %; 144~d = 0.50 %; 145~d = 0.22 %; I4"d = 0.44 %; '48~d = 0.37 %; ls0~d = 97.8 % (N.B. The emboldened figures represent the enriched isotopes)

6 Concentrations of elements in tracer solutions: Rb Tracer Soltltion: Concentration of Rb = pg/g. Sr Tracer Solution: Concentration of Sr = 2.04 pg/g. Sm-Nd Mixed Trucer SoZzrtion I: Concentration of Sm = pg/g. Concentration of Nd = pglg. Rb-Sr. Srn-Ncl Mixed Tracer Solution II: Concentration of Rb = pglg. Concentration of Sr = 4.23 pglg. Concentration of Sm = pglg. Concentration of Nd = pg/g. Error Magnification: The tracer solutions (spike) were used for Isotopic Dilution (ID) analyses for the precise determination of concentrations of elements. Though isotope dilution is a high-precision method, error magnification may occur if the proportions of sample to spike in a mixture are far from unity. During the isotope dilution analysis for the determination of Rb, Sr, Sm and Nd concentrations of metavolcanics the error magnification was generally below 2. The error magnification was determined using the following equation: where, EM is the Error Magnification; Rs, - ratio of two isotopes of the element under consideration in the spike; Rs, - ratio of the two isotopes in the sample and RM - ratio of the two isotopes in the mixture.

7 APPENDIX - IV Precision and Accuracy: The accuracy and precision of the analysis were checked periodically by measuring the required isotopic composition ratios of Isotopic Standards viz., SRM 987 for Sr and La Jolla for Nd (Figs. a & b). A pure element standard for Nd also was prepared using Ames Nd metal, whose Nd isotopic composition was precisely determined using the Clean Lab and TIMS facilities. The variation in Nd isotopic composition of Ames is given in Fig. c. Ames Nd was also used as an isotopic standard for Nd apart from La Jolla. The errors in the measurements were estimated as Absolute Standard Error and reported as Standard Error in ppm. The formula used for the calculation of Standard Error is as follows: where, i = measurement number; n = number of measurements; y = value of the ith measurement and rn = arithmetic mean of the measurements Mean 87~r186~r= Standard Error (ppm) = 5 I Total No. of Analyses = ! I Fig. a. Plot showing variation in s7~r/86~r ratio from 40 analyses of Sr isotopic standard, SRM 987, during the period between October 2005 and December The mean 87~r/s6~r ratio for the above measurements was with an external precision of 5 pprn Standard Error. The recommended 87~r/86~r ratio for SRM 987 is

8 Mean 143Nd1144Nd = Standard Error (ppm) = 4 Total No. of Analyses = I I Fig. b. Plot showing variation in 143~d/144~d ratio from 30 analyses of Nd isotopic standard, La Jolla, during the period between November 2005 and May The mean '43~d/'"~d ratio for the above measurements was with an external precision of 4 ppm Standard Error. The recommended 143~d/'44~d ratio for La Jolla is There was a sudden increase in the 143~d/'?4~d ratio during February, However, the ratio was indistinguishable from the recommended value * Mean '4'~dl'"~d= Standard Error (ppm) = Total No. of Analyses = ,,, --, i Fig. c. Plot showing variation in '43~d/'44~d ratio from 25 analyses of Nd metal standard, Ames - whose isotopic composition was precisely determined ('"Nd/'"~d = i 4), during the period between November 2005 and May The mean '43~d/'*4~d ratio for the above measurements was with an external precision of 4 ppm Standard Error.

9 Sr and Nd isotope compositions and elemental concentrations of Rb, Sr, S111 and Nd for the rock standards BHVO-1 and BCR-2 were verified periodically to establish the accuracy and precision of the isotopic measurements. Some of the analytical data for the above standards are given in Table a. Table a. Sr and Nd isotopic compositions and elemental concentrations of Rb, Sr, Sm and Nd determined for Rock Standards BHVO-1 and BCR-2. The recommended values (Mahoney et al., 2003 and URL: are also given in the table. 1 / Recommended i: i 6 I 11 * * * 0.3 / 25 & 2 Fractionation Correction for the ID Runs: The isotopic mass fractionation in the mass spectrometer can not be corrected using an internal normalization ratio for the isotope dilution analyses as the isotopic compositions are altered due to the addition of isotopic tracer (spike). Therefore, suitable fractionation correction factors were detelmined for Rb, Sr, Sm and Nd from repeated analyses of isotopic standards, such as, SRM987 for Sr, La Jolla and Ames Nd standards for Nd, calibrating solution prepared from Jolmson Matthey Rb metal for Rb and SPEX CertiPrep Sm elemental standard solution for Sm. The fractionation correction factor was calculated from the formula of the form, where, F is the fractionation factor; m - measured ratio; t - true ratio as determined from standard runs; AM - mass difference between the two isotopes considered. The fractionation factor was applied to the measured isotopic ratios (ID) of standards and samples and corrected for the isotopic mass fractionation.

CHAPTER -3. Methodology

CHAPTER -3. Methodology CHAPTER -3 Methodology METHODOLOGY Methodology includes field study and sampling, petrography, separation of mineral fractions for IJ-Pb isotope studies and trace element studies, processing of rock samples