Date File Created Name of Creator 1/16/2006 Lukas Zurcher Modified 2/7/2007 Georef Data 2004-014651 TI "Isotopic, geochemical, and temporal characterization of Proterozoic basement rocks in the Quitovac region, northwestern Sonora, Mexico; implications for the reconstruction of the southwestern margin of Laurentia." AU Iriondo-Alexander; Premo-Wayne-R; Martinez-Torres-Luis-M; Budahn-James-R; Atkinson-William-W Jr.; Siems-David-F; Guaras-Gonzalez-Blanca AF "University of Colorado at Boulder, Department of Geological Sciences, Boulder, CO, United States" SO "Geological Society of America Bulletin. 116; 1-2, Pages 154-170. 2004." PB "Geological Society of America (GSA). Boulder, CO, United States. 2004." RP USGSOP (Non-USGS publications with USGS authors) CP United-States PY 2004 LA English AB "A detailed geochemical characterization of 19 representative Proterozoic basement rocks in the Quitovac region in northwestern Sonora, Mexico, has identified two distinct Paleoproterozoic basement blocks that coincide spatially with the previously proposed Caborca and ""North America"" blocks. New U-Pb zircon geochronology revises their age ranges, the Caborca (1.78-1.69 Ga) and ""North America"" (1.71-1.66 Ga) blocks at Quitovac, and precludes a simple age differentiation between them. In addition, Grenvillian-age granitoids (ca. 1.1 Ga), spatially associated with the Caborca block have been identified at Quitovac. Nd isotopes and major- and trace- element geochemistry support the distinction of these Paleoproterozoic blocks. Granitoids of the ""North America"" block are characterized by depleted epsilon Nd values (3.4-3.9) and younger Nd model ages (1800-1740 Ma) and have lower K (sub 2) O, Y, Rb, Ba, Th, REE, and Fe/Mg values than coeval rocks of the Caborca block. The Caborca block granitoids are likewise characterized by slightly less depleted epsilon Nd (0.6-2.6) and older Nd model ages (2070-1880 Ma). Despite the subtle differences, granitoids from both the Caborca and ""North America"" blocks exhibit island arc-like affinities. We propose that the Proterozoic basement rocks from the Quitovac region are an extension of the Proterozoic crustal provinces in the southwestern United States. Specifically, rocks of the Caborca block exhibit an affinity to rocks of either the Yavapai province or the Mojave-Yavapai transition zone, whereas rocks of the ""North America"" block have signatures similar to those of the Mazatzal province or possibly the Yavapai province of Arizona. The new isotopic ages and geochemical data do not support the existence of the Late Jurassic Mojave-Sonora megashear at Quitovac, as originally proposed. However, the Quitovac region accounts only for a small fraction of the Proterozoic basement in Sonora, so these findings do not eliminate the possibility of a megashear elsewhere in northern Sonora. Our new data create the possibility of alternative hypotheses for the distribution of Paleoproterozoic crustal provinces in southwestern North America that affect reconstructions of the original southwestern margin of Laurentia, and reduce uncertainties in the configuration, timing, and existence of the Proterozoic supercontinent, Rodinia." DE absolute-age; basement-; block-structures; crust-; dates-; faults-; geochemistry-; granitic-composition; igneous-rocks; isotope-ratios; isotopes-; Laurentia-; lead-; major-elements; metals-; metamorphic-rocks; metasedimentary-rocks; Mexico-; Nd-144-Nd-143; neodymium-; nesosilicates-; orthosilicates-; paleogeography-; Pb-206-Pb-204; Pb-208-Pb-204; Precambrian-; Proterozoic-; Quitovac-Mexico; radioactive-isotopes; rare-earths; shear-zones; silicates-; Sm-Nd; Sonora-Mexico; stable-isotopes; systems-; tectonics-; trace-elements; U-Pb; upper-Precambrian; zircon- CC 03-Geochronology DT Serial BL Analytic MC LAT: N312000; N313000; LONG: W1124000; W1125500. NN With GSA Data Repository Item 2004027. IL "Refs: 85; illus. incl. 3 tables, geol. sketch maps." RF "GeoRef, Copyright 2004, American Geological Institute. Reference includes data supplied by the Geological Society of America, Boulder, CO, United States" IS 0016-7606 CO BUGMAF AN 2004-014651 UD 200405 Table Heading "Table 2. Sample Location, Classification, Mineral Assemblages And U-Pb Zircon Ages For Studied Proterozoic Basement Rocks In The Quitovac Region, Northwest Sonora, Mexico" Table Heading "Table Dr3. Summary Of U-Pb Zircon Geochronology For Proterozoic Basement Rocks In The Quitovac Region, Nw Sonora, Mexico" Table Heading "Table Dr4. U-Th-Pb Analytical Data For Whole-Rock Samples From Proterozoic Basement Rocks In The Quitovac Region, Nw Sonora, Mexico" Table Heading "Table Dr5. Sm-Nd Analytical Data For Whole-Rock Samples From Proterozoic Basement Rocks In The Quitovac Region, Nw Sonora, Mexico" Table Heading "Table Dr6. Rb-Sr Analytical Data For Whole-Rock Samples From Proterozoic Basement Rocks In The Quitovac Region, Nw Sonora, Mexico" Table Heading "Table Dr7. Major- And Trace-Element Compositions Of Proterozoic Basement Rocks In The Quitovac Region, NW Sonora, Mexico" Table Heading "Table Dr8. Rare-Earth Element (REE) Compositions Of Proterozoic Basement Rocks In The Quitovac Region, Nw Sonora, Mexico" Modes volume percent Sample Data Item Age Age_Max Age_Min LatDD LongDD Loc_prec Location_Name Sample_Comment Sample_Comment Sample_Comment Sample_Comment Sample_Comment rock_class Rock_Type material Sample_Comment Sample_Comment Sample_Comment U Th Pb 206_204PB 207_204PB 208_204PB ITEM ITEM Sm Nd 147SM/144ND 143ND/144ND 143ND/144ND_STDEV ND143_ND144_INITIAL E_ND Rb Sr 87RB/86SR 87Sr/86Sr 87SR/86SR_STDEV 87SR_86SR_INITIAL E_SR SiO2 Al2O3 Fe2O3T MgO CaO Na2O K2O TiO2 P2O5 MnO LOI Total Y Nb Pb Fe K Rb Sr Cs Ba Th U Zr Hf Ta W Sc Cr Co Ni Zn As Sb Au La Ce Nd Sm Eu Gd Tb Ho Tm Yb Lu State Units Ma Ma Ma DD DD DD ppm ppm ppm ppm ppm absolute ppm ppm absolute Wt % Wt % Wt % Wt % Wt % Wt % Wt % Wt % Wt % Wt % Wt % Wt % ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppb ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm Method 1 1 1 2 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 4 4 4 4 4 4 4 4 4 4 4 4 4 4 5 5 5 5 5 5 5 5 5 5 5 5 6 6 6 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 Sample Name CA-1 1747.7 1755.9 1739.5 31.48527778 -112.7722 0.001 Quitovac I Caborca block samples Tectonized granite Qtz + Pl + Kfs + Mic + Bt "Opaq, Ap, Zrn, Tur" granite plutonic mineral 1.07 (MSWD) 358 (Concordia_Lower-intercept_Age) 35 (Concordia_Lower-intercept_Age_error) 2.27 9.93 10.9 23.432 16.138 42.566 14.91 (238U/204Pb) 67.5 (232Th/204Pb) 6.43 32.1 0.121 0.511894 14 0.510503 2.6 150.1 134.9 3.2376 0.769227 15 71.07 13.94 3.45 0.47 0.99 3.76 4.7 0.32 0.12 0.05 0.95 99.82 46 12 12 23700 33000 143 131 3.4 825 13.2 2.7 248 6.46 1.09 1.63 5.88 15.5 3 9.4 31.7 0.9 0.44 1.35 42.1 82.5 34 6.61 0.82 5.91 1.01 1.42 0.69 4.39 0.66 Sonora CA-4 1748 1814 1682 31.47805556 -112.8536 0.001 El Tullido Caborca block samples Two-mica granite Qtz + Pl + Kfs + Mic Ms + Bt "Ap, Opaq, Zrn" granite plutonic mineral 8.9 (MSWD) 1026 (Concordia_Lower-intercept_Age) 87 (Concordia_Lower-intercept_Age_error) 0.72 3.15 10.4 19.34 15.76 38.993 4.47 (238U/204Pb) 20.3 (232Th/204Pb) 5.08 24.1 0.1269 0.511863 14 0.510404 0.6 96 163.7 1.7037 0.747175 21 0.704358 27.5 70.41 14.1 3.5 0.53 1.48 3.81 4.61 0.33 0.13 0.06 0.7 99.66 31 7.1 11 23600 34600 95.7 163 1.69 1080 3.24 1.01 256 6.52 0.41 0.53 6.71 12.4 3.36 7.56 33.4 0.59 0.12 0.57 27.5 52.6 24.8 5.37 1 4.96 0.83 1.2 0.51 2.98 0.44 Sonora CA-11 1740 1770 1710 31.57972222 -112.7864 0.001 La Silla Sur I Caborca block samples Alkaline granite Qtz + Kfs + Pl + Mic + Bt "Opaq, Sph, Zrn, Ap" granite plutonic mineral 12 (MSWD) 273 (Concordia_Lower-intercept_Age) 62 (Concordia_Lower-intercept_Age_error) 3 11.2 19 19.337 15.703 38.68 10.19 (238U/204Pb) 39.3 (232Th/204Pb) 5.07 23.4 0.1306 0.51195 19 0.510456 1.4 179.9 248.3 2.1018 0.735389 21 71.25 14 3.28 0.47 1.53 3.69 4.31 0.23 0.13 0.05 0.45 99.39 29 7.5 20 24600 31300 180 258 7.56 1030 9.19 3.19 261 6.67 1.14 0.58 7.97 12.1 3.92 10.2 32.8 0.43 0.12 0.27 29 56.9 25.1 5.81 0.91 5.35 0.93 1.15 0.42 2.52 0.34 Sonora CA-12 1763 1775 1751 31.56194444 -112.8394 0.001 Bustamante II Caborca block samples Quartz granite Qtz + Pl + Kfs + Mic + Bt Ms "Opaq, Zrn" granite plutonic mineral N.A.# (MSWD) 1126 (Concordia_Lower-intercept_Age) 1.02 7.59 21.306 16.006 40.898 9.22 (238U/204Pb) 2.78 15.8 0.1058 0.511752 12 0.510525 3.4 32.8 120.3 0.7911 0.72722 120 0.707166 67.7 77 10.52 3.32 0.66 1.59 2.68 2.37 0.17 0.02 0.05 0.86 99.24 21 5.4 10 23681 17500 35.4 146 1.26 1150 4.04 1.43 257 7.4 0.4 0.32 7.76 19.1 0.99 11.4 48.2 0.45 0.17 1.7 26.3 44 17.3 3.06 1.61 2.64 0.42 0.66 0.42 3.09 0.52 Sonora CA-14 1699 1715 1683 31.50694444 -112.8556 0.001 San Antonio Caborca block samples Calc-alkaline granite Qtz + Kfs + Mic + Pl + Bt "Zrn, Sph, Ap, Opaq" granite plutonic mineral N.A.# (MSWD) 284 (Concordia_Lower-intercept_Age) 170 (Concordia_Lower-intercept_Age_error) 1.49 7.45 9.9 21.604 15.932 41.262 10.35 (238U/204Pb) 53.6 (232Th/204Pb) 5.38 24.4 0.1333 0.51204 10 0.510551 2.2 124.5 162.7 2.2237 0.75454 420 70.52 14.07 3.21 0.48 1.53 3.81 4.64 0.31 0.1 0.06 0.48 99.21 41 11 12 22500 37700 126 179 1.27 1070 10.5 1.97 226 5.99 0.93 0.6 5.9 10.6 3.16 11.3 31.6 0.32 0.11 0.9 33.6 67 28.7 5.84 0.9 5.76 0.96 1.45 0.63 4.05 0.61 Sonora CA-15 1693.3 1701.5 1685.1 31.52277778 -112.8508 0.001 La Toita Caborca block samples Calc-alkaline granite Qtz + Kfs + Pl + Mic + Bt " Opaq, Sph, Ap" granite plutonic mineral N.A. (MSWD) 328 (Concordia_Lower-intercept_Age) 110 (Concordia_Lower-intercept_Age_error) 1.5 10.4 13.1 20.138 15.818 41.323 7.78 (238U/204Pb) 55.7 (232Th/204Pb) 6.23 30.6 0.1229 0.511875 10 0.510507 1.2 118.3 167.8 2.0485 0.75208 14 70.15 14.25 3.27 0.49 1.48 3.59 4.89 0.32 0.1 0.06 0.41 99.01 39 9.2 14 23900 40900 125 187 1.92 1140 11.6 2.23 245 6.64 1.06 0.49 6.76 10.1 3.31 4.7 40.1 0.25 0.09 2.43 37.5 75.1 33.9 6.91 0.97 6.67 1.06 1.55 0.72 4.5 0.67 Sonora CA-16 1747 1757 1737 31.49277778 -112.7842 0.001 Quitovac II Caborca block samples Calc-alkaline granite Qtz + Kfs + Pl + Mic Bt Opaq granite plutonic mineral N.A.# (MSWD) 402 (Concordia_Lower-intercept_Age) 71 (Concordia_Lower-intercept_Age_error) 2.44 9.15 11.1 23.188 16.087 41.877 15.57 (238U/204Pb) 60.4 (232Th/204Pb) 5.53 26.9 0.1243 0.511871 9 0.510443 1.3 129.6 130.5 2.8888 0.764834 28 70.11 13.8 3.16 0.48 1.32 3.62 4.78 0.31 0.13 0.06 1.35 99.12 34 11 14 22200 41800 138 156 1.9 1000 12.6 3.5 243 6.74 1.32 0.48 6.27 12.9 3.14 6.09 29 2.86 0.76 0.82 27.2 56.8 27.3 6.23 0.84 5.66 0.96 1.49 0.65 4.39 0.66 Sonora CA-17 1777 1796 1758 31.57805556 -112.785 0.001 La Silla Sur II Caborca block samples Calc-alkaline granite Qtz + Pl + Kfs + Mic Bt + Am "Opaq, Sph, Ap" granite plutonic mineral 1.16 (MSWD) 432 (Concordia_Lower-intercept_Age) 51 (Concordia_Lower-intercept_Age_error) 2.05 16.4 34 19.296 15.701 39.237 3.92 (238U/204Pb) 32.4 (232Th/204Pb) 5.63 30.2 0.1124 0.511745 13 0.510432 1.9 149.9 231.1 1.8839 0.746334 22 69.57 14.19 3.37 0.54 1.45 3.1 5.91 0.21 0.09 0.06 0.46 98.95 26 5.3 30 24300 50100 156 252 4.41 1470 12.3 2.25 248 6.3 0.89 1.25 13.5 14.6 2.47 7.66 33 1.15 0.25 0.17 33.8 67.6 29.9 6.06 0.97 5.55 0.87 1.09 0.42 2.7 0.42 Sonora CA-18 1718.8 1726.7 1710.9 31.56277778 -112.7775 0.001 San Fernando Caborca block samples Calc-alkaline granite Qtz + Pl + Kfs + Mic Bt "Opaq, Sph" granite plutonic mineral 1.4 (MSWD) 207 (Concordia_Lower-intercept_Age) 38 (Concordia_Lower-intercept_Age_error) 3.43 16.8 26.3 21.269 15.885 39.961 8.83 (238U/204Pb) 44.6 (232Th/204Pb) 4.92 28.6 0.1038 0.511671 10 0.510498 1.7 142.2 139 2.9806 0.780985 62 -69.3 71.84 13.95 2.96 0.34 1.29 3.74 4.1 0.23 0.11 0.06 0.71 99.33 21 6.8 26 20300 36900 144 157 1.72 756 15.6 4.15 151 4.58 0.47 0.4 4.4 8.47 2.3 7.5 41.2 0.47 0.14 1.09 35.1 64.4 25.6 4.48 0.83 4.27 0.61 0.77 0.32 1.98 0.3 Sonora CA-19 1718 1878 1558 31.5825 -112.8531 0.001 Lomas Rojas Caborca block samples Two-mica granite Qtz + Kfs + Pl + Mic Bt + Ms "Opaq, Zrn" granite plutonic mineral 6.8 (MSWD) 275 (Concordia_Lower-intercept_Age) 820 (Concordia_Lower-intercept_Age_error) 3.06 13.1 11.8 22.83 16.07 42.256 18.5 (238U/204Pb) 81.5 (232Th/204Pb) 6.39 31.1 0.124 0.511873 10 0.510472 1.2 104.4 157.9 1.9208 0.75121 260 -18.6 70.28 13.95 3.54 0.5 1.27 3.55 4.58 0.31 0.11 0.05 0.86 99 42 12 13 24900 36700 110 175 1.23 1070 13.7 3.57 236 6.56 1.18 1.12 6.46 13.7 3.36 4.5 31.6 0.62 0.36 2.19 37.9 75.8 34 6.96 0.95 6.89 1.09 1.66 0.74 4.71 0.69 Sonora CA-20 1708.4 1713.6 1703.2 31.46305556 -112.8381 0.001 El Molino Caborca block samples Calc-alkaline granite Qtz + Kfs + Pl + Mic + Bt "Ap, Sph, Opaq, Fe ox." granite plutonic mineral 0.027 (MSWD) 159 (Concordia_Lower-intercept_Age) 93 (Concordia_Lower-intercept_Age_error) 1.95 10.6 9.86 22.96 16.072 44.08 14.37 (238U/204Pb) 80.6 (232Th/204Pb) 6.42 33.5 0.1158 0.511769 18 0.510468 0.8 147.2 138.5 3.0924 0.769616 22 70.27 13.96 3.52 0.49 1.36 3.64 4.78 0.32 0.1 0.06 0.4 98.9 39 11 11 25300 36400 153 155 3.95 983 13.6 2.64 260 7.1 0.95 0.73 6.52 18.6 3.33 8.38 33.2 1.86 0.36 0.91 44.8 85.4 34.8 7 0.95 6.61 1.06 1.51 0.69 4.52 0.66 Sonora CAG-2 1126 1166 1086 31.56611111 -112.8217 0.001 Bustamante I Grenvillian-Caborca block samples Alkaline granite Qtz + Pl + Mic + Bt + Am "Zrn, Ap, Opaq" granite plutonic mineral N.A.# (MSWD) 573 (Concordia_Lower-intercept_Age) 190 (Concordia_Lower-intercept_Age_error) 3.68 13.2 25 19.597 15.706 38.936 9.58 (238U/204Pb) 35.5 (232Th/204Pb) 12 58 0.1247 0.512034 10 0.511113 -1.4 142.6 182.2 2.274 0.748642 25 -125.4 66.32 14.41 5.97 0.72 2.18 3.4 4.75 0.68 0.21 0.1 0.95 99.69 62 24 25 40800 36200 136 179 4.25 1700 15 4.46 582 13.5 1.82 1.27 10.3 11.4 5.77 11.9 93.3 0.99 0.29 0.13 54.7 114 55.7 11.9 3.22 11.1 1.77 2.33 0.91 5.75 0.85 Sonora CAG-13 1112 1212 1012 31.56027778 -112.8353 0.001 Bustamante III Grenvillian-Caborca block samples Alkaline granite Qtz + Kfs + Mic + Pl + Bt "Opaq, Zrn, Sph" granite plutonic mineral N.A.# (MSWD) 405 (Concordia_Lower-intercept_Age) 570 (Concordia_Lower-intercept_Age_error) 3.84 18.7 24.9 21.513 15.928 40.651 10.54 (238U/204Pb) 53.2 (232Th/204Pb) 5.82 34.7 0.1012 0.511734 10 0.510996 -4 211.4 194.9 3.1662 0.797744 33 68.84 15.17 2.75 0.49 2.01 3.65 4.7 0.25 0.09 0.06 0.96 98.97 21 6.3 29 20100 35300 215 212 6.29 1500 19.6 4.6 256 7.48 0.56 3.46 4.03 11.9 2.75 10.7 49.4 0.7 0.13 0.83 53.4 93 35.6 6.24 2.11 5.56 0.66 0.87 0.36 2.36 0.36 Sonora NA-3 1714 1723.5 1704.5 31.4125 -112.7131 0.001 El Chacn III North American block samples Quartz monzodiorite Qtz + Pl + Kfs + Bt + Am "Zrn, Sph, Ap, Opaq" Quartz monzodiorite plutonic mineral 0.68 (MSWD) 199 (Concordia_Lower-intercept_Age) 180 (Concordia_Lower-intercept_Age_error) 1.38 4.12 8.83 18.842 15.634 38.022 9.99 (238U/204Pb) 30.7 (232Th/204Pb) 4.25 22.2 0.1155 0.51192 16 0.510618 3.9 76.9 515.1 0.4323 0.713203 21 0.702552 1.2 64.67 15.36 5.79 2.04 4.17 4.2 1.74 0.74 0.26 0.08 0.55 99.6 17 12 9.2 36900 11600 72.4 552 3.89 710 3.48 1.49 168 4.14 1.06 0.37 9.62 43.2 14.7 30.1 56.2 0.24 0.1 0.26 21.3 43.6 20.5 4.23 1.16 3.41 0.48 0.59 0.21 1.34 0.19 Sonora NA-5 1656.8 1661.2 1652.4 31.41777778 -112.7622 0.001 La Colorada North American block samples Alkaline granite Qtz + Pl + Mic + Kfs Bt "Fe ox., Zrn" granite plutonic mineral 0.13 (MSWD) 160.1 (Concordia_Lower-intercept_Age) 7.8 (Concordia_Lower-intercept_Age_error) 4.07 13.1 26.4 19.335 15.683 38.286 9.88 (238U/204Pb) 32.9 (232Th/204Pb) 4.19 23.8 0.1062 0.511769 13 0.510612 2.3 123.8 132.9 2.707 0.759359 24 73.74 13.58 1.73 0.17 0.81 3.12 5.69 0.14 0.11 0.02 0.41 99.52 6.9 6.5 26 11000 44800 122 146 1.23 690 16.1 5.08 117 3.68 0.17 0.5 1.89 11.9 1.16 9.65 22.3 0.56 0.09 0.34 38.1 70.8 27.4 4.94 0.68 3.61 0.41 0.36 0 0.52 0.08 Sonora NA-7 1703.2 1711.4 1695 31.41666667 -112.7367 0.001 El Chacn II North American block samples Calc-alkaline granite Qtz + Pl + Kfs + Bt "Ap, Sph, Opaq, Zrn, Fe ox." granite plutonic mineral 0.15 (MSWD) 162 (Concordia_Lower-intercept_Age) 110 (Concordia_Lower-intercept_Age_error) 0.66 2.56 8.78 18.356 15.584 38.314 4.72 (238U/204Pb) 19 (232Th/204Pb) 1.61 11.2 0.0869 0.511578 19 0.510605 3.4 58.7 344.9 0.4924 0.713244 15 0.701191 -18.4 72.24 14 3.62 0.71 2.53 4.5 1.28 0.34 0.15 0.04 0.38 99.79 4 5.4 9 24500 13000 57.8 355 2.81 482 2.78 1.12 249 6.3 0.24 0.5 2.76 13.5 5.26 8.19 25.4 0.56 0.18 0.1 20 30.3 9.92 1.7 0.9 1.37 0.14 0.17 0.07 0.39 0.07 Sonora NA-8 1704.9 1711.1 1698.7 31.42111111 -112.7389 0.001 El Chacn I North American block samples Calc-alkaline granite Qtz + Kfs + Pl + Bt "Opaq, Ap, Sph, Zrn, Fe ox." granite plutonic mineral 0.55 (MSWD) 214 (Concordia_Lower-intercept_Age) 52 (Concordia_Lower-intercept_Age_error) 0.64 6.64 12.6 17.47 15.496 39.027 3.2 (238U/204Pb) 34.5 (232Th/204Pb) 3.06 17.6 0.1048 0.51179 14 0.510615 3.6 90.3 351.8 0.7433 0.718907 21 0.700692 -25.5 68.17 14.86 4.3 1.47 3.25 4.12 2.15 0.51 0.19 0.06 0.55 99.63 13 10 13 28400 17200 92.6 377 5.08 577 5.9 0.87 157 4.05 0.78 0.8 7.07 33.7 10.6 21.8 45.6 0.75 0.15 0.49 25.1 44.5 16.5 3.12 0.81 2.67 0.36 0.46 0.2 1.17 0.16 Sonora Method Data Institution# GEOREF# Method_ comment 1 U-PBC:ZIRCON 106 2004-014653 Upper-intercept age calculated using Isoplot/Ex regression treatment of Ludwig (1998) and interpreted here as possible crystallization age of the rock. Errors are given at the 95% confidence level. 2 TABLE 106 2004-014651 3 U-PB 106 2004-014651 4 ID-MS:WR 106 2004-014652 "Concentration uncertainties for Sm and Nd are ~0.5 % and ~0.1 %, respectively. See GSA Data Repository item 2004027 for sample preparation methodology. Isotopic ratios corrected for blank and mass fractionation, 143Nd/144Nd data are normalized to 146Nd/144Nd = 0.7219 and adjusted for instrumental bias to 143Nd/144Nd = 0.511860 for the La Jolla Nd standard. The mean value of 143Nd/144Nd for 30 analyses of the La Jolla Nd standard was 0.511865 10. Uncertainties correspond to the last significant figure(s) at the 95% confidence level.Initial 143Nd/144Nd ratios and ENd are calculated using U-Pb zircon ages from Table DR3; Lambda = 6.54 x 10-12/yr; present day (143Nd/144Nd)CHUR = 0.512638, and (147Sm/144Nd)CHUR = 0.1967, where CHUR = chondritic uniform reservoir. Nd model ages (TDM) are calculated relative to depleted mantle (DM) evolution by solving for T (age in Ga) in the expression: Nd(T) = 0.25T2 - 3T + 8.5 (DePaolo, 1981).Concentration uncertainties for Rb and Sr are ~1.0 % and ~0.5 %, respectively. See GSA Data Repository item 2004027 for methodology. Isotopic ratios corrected for blank and mass fractionation, 87Sr/86Sr data are normalized to 86Sr/88Sr = 0.1194 and adjusted for instrumental bias to 87Sr/86Sr = 0.710265 for NBS SRM 987 standard. The mean value of 87Sr/86Sr for 30 analyses the Sr standard was 0.710265 10. Uncertainties correspond to the last significant figure(s) at the 95% confidence level.Initial 87Sr/86Sr ratios and Sr are calculated using U-Pb zircon ages from Table DR3; = 1.42 x 10-11/yr; present day (87Sr/86Sr)UR = 0.7045, and (87Rb/86Sr)UR = 0.0824, where UR = Uniform Reservoir. Numbers in parentheses are highly unreliable to impossible, owing mostly to 87Rb/86Sr values of ~2.0 or greater and a large correction for radiogenic 87Sr." 5 WDXRF:WR 106 2004-014651 Total Fe as Fe2O3. LOI = loss on ignition. Major elements in weight percent. Trace elements in ppm except Au in ppb. 6 ICP-MS:WR 106 2004-014651 7 INAA:WR 106 2004-014651