129.6 ± ± 2.0. U (ppm) T ± 2.9

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DR00. ±. 0. ±.. ±.0. ±.. ±..0 ±..0 ±. 00 µm. ±.. ±..0 ±.. ±.. ±. 0. ±.. ±. 0. ±.0. ±. 0. ±. 0. ±.. ±..0 ±.. ±. 0 0.

CM- (b). DJ-.0 ±.. ±. 0 µm. ±.0. ±.. ±.0. ±. 00 µm. ±.. ±. (a). DL0-. ±.. ±. 0. ±. 0. ±.. ±.. ±.. ±.. ±.0. ±. 00 µm. ±.0. ±. 0. ±. (f) SHRIMP data h/u.

ZG- 00 0 0 0 Th (ppm) 0 0DL0 0CM- 0JBT0 0JBT0 0JBT0 0ZG0-0 Fig. DR (Zhu et al.

large igneous province, southeastern Tibet.

Beijing SHRIMP II Center, Chinese Academy of Geological Sciences. U vs.

1 DR00. ±. 0. ±.. ±.0. ±.. ±..0 ±..0 ±. 00 µm. ±.. ±..0 ±.. ±.. ±. 0. ±.. ±. 0. ±.0. ±. 0. ±. 0. ±.. ±..0 ±.. ± ±.. ±. 0 DL0- DJ- CM- QG- ZG-. ±. (d). QG- U (ppm). ±.. ±.. ±.. ±.. ±.. ±. (c). CM- (b). DJ-.0 ±.. ±. 0 µm. ±.0. ±.. ±.0. ±. 00 µm. ±.. ±. (a). DL0-. ±.. ±. 0. ±. 0. ±.. ±.. ±.. ±.. ±.0. ±. 00 µm. ±.0. ±. 0. ±. (f) SHRIMP data h/u. =0 T 0 0 h/u. = T 0 µm. ±.. ±.. ±. LA-ICPMS data 0 (e). ZG Th (ppm) 0 0DL0 0CM- 0JBT0 0JBT0 0JBT0 0ZG0-0 Fig. DR (Zhu et al.) Cathodoluminescence (CL) images of zircon SHRIMP dating for rocks of the Comei large igneous province, southeastern Tibet. Circles indicate the locations of SHRIMP U-Pb dating, which were performed at the Beijing SHRIMP II Center, Chinese Academy of Geological Sciences. U vs. Th plot (f) showing all analyzed zircons are magmatic.

0JBT0 ± ± ± 0 ± ± ± ± ± ± ± ± 00 µm ± ± 0 ± 0 ± ±

0JBT0 ± 0 ± 0 ± ± ± ± ± 0 ± ± ± ± 0 ± ± 0 ± ± ± ±

0JBT0 ± 0 ± 0 00 µm ± ± ± ± ± ± ± 00 µm 00 µm ± 0

LA-ICPMS dating for rocks of the Comei large

2 (a). 0DL0 (b). 0CM- ± ± ± ± ± ± 0 ± ± ± ± ± 00 µm ± ± (c). 0JBT0 ± ± ± 0 ± ± ± ± ± ± ± ± 00 µm ± ± 0 ± 0 ± ± ± (e). 0JBT0 ± 0 ± 0 ± ± ± ± ± 0 ± ± ± ± 0 ± ± 0 ± ± ± ± 00 µm ± (f). 0ZG0- ± 0 ± ± 0 ± 0 ± (d). 0JBT0 ± 0 ± 0 00 µm ± ± ± ± ± ± ± 00 µm 00 µm ± 0 ± ± ± ± ± ± 0 ± ± ± ± 0 ± ± 0 ± ± ± Fig. DR (Zhu et al.) Cathodoluminescence (CL) images of zircon LA-ICPMS dating for rocks of the Comei large igneous province, southeastern Tibet. Circles indicate the locations of LA-ICPMS U-Pb dating, which were performed at the Institute of Geology and Geophysics, Chinese Academy of Sciences, China.

3 0.0 spots, % conf.: Mean =. ±. MSWD = 0. (a) 0.0 spots, % conf.: Mean =. ±. MSWD =.0 (b) DL DJ spots, % conf.: Mean = 0. ±.0 MSWD =. 0 0 CM- (c) spots, % conf.: Mean =. ±.0 MSWD =. 0 QG- (d) spots, % conf.: Mean = 0.0 ±.0 MSWD =.0 0 ZG- (e) Pb/ U Fig. DR (Zhu et al.) Concordia plot of zircon SHRIMP dating for rocks of the Comei large igneous province, southeastern Tibet. Weighted mean ages are σ analytical errors. Box heights in inset are σ. Common Pb corrected using measured 0 Pb. Inset shows an error range for each spot and age variation of analyzed spots in individual sample.

4 spots, ± σ: Mean = ± MSWD = 0. 0DL0 (a) spots, ± σ: Mean = ± MSWD = 0. 0JBT (c) spots, ± σ: Mean = ± MSWD = 0. (d) 0CM JBT spots, ± σ: Mean = ± MSWD = 0. (b) spots, ± σ: Mean = ± MSWD = JBT Pb/ U (e) (f) spots, ± σ: Mean = ± MSWD = 0. 0ZG Pb/ U Fig. DR (Zhu et al.) Concordia plot of zircon LA-ICPMS dating for rocks of the Comei large igneous province, southeastern Tibet. Weighted mean ages are σ analytical error. Common lead was corrected using the common lead correction function proposed by Anderson (00). Box heights in inset are σ. Inset shows an error range for each spot and age variation of analyzed spots in individual sample.

5 TABLE DR. SUMMARY OF ZIRCON U-PB ISOTOPIC AGES FOR SAMPLES OF THE COMEI LIP IN SOUTHEASTERN TIBET No. Sample Location GPS position Rock unit Rock type Dating method Age ()* Reference YM0- Western Yamzho Yum Tso N.00, E0. Late Triassic strata Diabasic dike SHRIMP..0 [] YM0- Western Yamzho Yum Tso N., E0. Late Triassic strata Diabasic dike SHRIMP.. [] SX(0)- Rimowa village N., E0. Sangxiu Formation Dacite SHRIMP.0.0 [] 0JBT0 Rimowa village N., E0. Sangxiu Formation Dacite LA-ICPMS [] DL0- Dalong village N., E0. Early to Middle Triassic strata Diabasic dike SHRIMP. ±. [] 0DL0 Dalong village N., E0. Early to Middle Triassic strata Diabasic dike LA-ICPMS ± [] DJ- North of Dongjia village N., E0. Early to Middle Jurassic strata Gabbro SHRIMP. ±. [] 0JBT0 North of Dongjia village N., E0. Early to Middle Jurassic strata Gabbro LA-ICPMS ± [] 0JBT0 North of Dongjia village N., E0. Early to Middle Jurassic strata Diabasic dike LA-ICPMS ± [] 0 0CM- North of Comei County N., E.0 Middle Jurassic strata Gabbro LA-ICPMS ± [] CM- North of Comei County N., E. Middle Jurassic strata Diabasic dike SHRIMP 0. ±.0 [] ZG- Southwestern Chigu Tso N., E.0 Middle Jurassic strata Pyroxenite SHRIMP 0.0 ±.0 [] 0ZG0- Southwestern Chigu Tso N.0, E. Middle Jurassic strata Gabbro LA-ICPMS ± [] QG- Qonggyai reservoir N., E. Late Triassic strata Diabasic dike SHRIMP.. [] CN0- Kada village N.0, E. Lakang Formation Gabbro SHRIMP. ±. [] *Note: Ages are listed with uncertainty. [] = re-calculated from Jiang et al. (00); [] = Zhu et al. (00); [] = this study; [] = Zhu et al. (00a).

6 References cited Jiang, S.H., Nie, F.J., Hu, P., and Liu, Y., 00, Important spreading event of the Neo-Tethys ocean during the Late Jurassic and Early Cretaceous: Evidence from Zircon U-Pb SHRIMP dating on diabase in Nagarze, southern Tibet: Acta Geologica Sinica, v. 0, p.. Zhu, D.C., Pan, G.T., Mo, X.X., Wang, L.Q., Liao, Z.L., Jiang, X.S., and Geng, Q.R., 00, SHRIMP U-Pb zircon dating for the dacite of the Sangxiu Formation in the central segment of Tethyan Himalaya and its implications: Chinese Science Bulletin, v. 0, p.. Zhu, D.C., Mo, X.X., Pan, G.T., Zhao, Z.D., Dong, G.C., Shi, Y.R., Liao, Z.L., and Zhou, C.Y., 00a, Petrogenesis of the earliest Early Cretaceous basalts and associated diabases from Cona area, eastern Tethyan Himalaya in south Tibet: interaction between the incubating Kerguelen plume and eastern Greater India lithosphere?: Lithos, v. 00, p., doi: 0.0/j.lithos

7 TABLE DR. SHRIMP ZIRCON AGE DATA FOR SAMPLES OF THE COMEI LIP IN SOUTHEASTERN TIBET Spot f0 c (%) U (ppm) Th (ppm) Th/U 0 Pb* (ppm) 0 Pb*/ U ( ± ) 0 Pb*/ U ( ± ) 0 Pb/ U (; ± ) DL0- weighted mean ( spots, level, MSWD = 0.). ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ±. DJ- weighted mean ( spots, level, MSWD =.0):. ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ±. CM- weighted mean (0 spots, level, MSWD =.) 0. ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ±.

8 QG- weighted mean ( spots, without spot., level, MSWD =.). ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ±. ZG- weighted mean ( spots, level, MSWD =.0) 0.0 ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ±. Note: f0 c denotes the proportion of common 0 Pb in total measured 0 Pb *. * denotes radiogenic lead. Note : SHRIMP zircon U Pb dating Zircons were separated from samples using standard density and magnetic separation techniques at the Special Laboratory of the Geological Team of Hebei Province, China. Zircon grains, together with the zircon U-Pb standard TEMORA (Black et al., 00), were cast in an epoxy mount, which was then polished to section the crystals in half for analysis. Zircons were documented with transmitted and reflected light micrographs as well as cathodoluminescence (CL)

9 images to reveal their internal structures, and the mount was vacuum-coated with a 00-nm layer of high-purity gold. Under the guidance of zircon CL images, the zircons were analyzed for U-Pb isotopes and U, Th, and Pb concentrations using a SHRIMP II ion microprobe at the Beijing SHRIMP Center, Chinese Academy of Geological Sciences, Beijing, following the procedures reported by Liu et al. (00). The U-Th-Pb isotopic ratios were determined relative to the TEMORA standard zircon corresponding to 0 Pb/ U = 0.0 (Black et al. 00), and the absolute abundances of U-Th-Pb element were calibrated to the standard zircon SL. Analyses of the TEMORA standard zircon were interspersed with unknown sample grains, following operating and data processing procedures described by Williams (). The reference zircon was analyzed after every fourth analysis. Measured compositions were corrected for common Pb using the 0 Pb method (Compston et al., ), and data processing was carried out using Isoplot (Ludwig, 00). Uncertainties on individual analyses are reported at the -sigma level; mean ages for pooled 0 Pb/ U results are quoted at the -sigma level. References cited: Black, L.P., Kamo, S.L., Allen, C.M., Aleinikoff, J.N., Davis, D.W., Korsch, R.J., and Foudoulis, C., 00, TEMORA : A new zircon standard for Phanerozoic U-Pb geochronology: Chemical Geology, v. 00, p. -0. Compston, W., Williams, I.S., Meyer, C.,, U-Pb geochronology of zircons from Lunar Breccia using a sensitive high mass resolution ion microprobe: Journal of Geophysical Research, v., p. -. Liu, D.Y., Jian, P., Kröner, A., and Xu, S.T, 00, Dating of prograde metamorphic events deciphered from episodic zircon growth in rocks of the Dabie Sulu UHP complex, China: Earth and Planetary Science Letters, v. 0, p. 0-. Ludwig, K.R., 00, Using Isoplot/Ex, Version.: a geochronological toolkit for Microsoft Excel. Berkeley Geochronology Center Special Publication, No. a:. Williams, I.S.,, U-Th-Pb geochronology by ion microprobe. In: McKibben, M.A., Shanks, W.C., Ridley, W.I., eds. Applications of Microanalytical Techniques to Understanding Mineralizing Processes: Reviews in Economic Geology, v., p. -.

10 TABLE DR. ZIRCON LA-ICPMS U-PB DATA FOR SAMPLES OF THE COMEI LIP IN SOUTHEASTERN TIBET Analysis Th U Pb* Th/U 0 Pb*/ 0 Pb* 0 Pb*/ U 0 Pb*/ U 0 Pb*/ 0 Pb 0 Pb*/ U 0 Pb*/ U Ratio Ratio Ratio Age Age Age 0DL0: diabasic dike, spots, level, mean =, MSWD = CM-: gabbro, spots (without spot.,.), level, mean =, MSWD =

11 JBT0: diabasic dike, spots, level, mean =, MSWD =

12 0JBT0: gabbro, 0 spots, level, mean =, MSWD = JBT0: dacite, spots, level, mean =, MSWD =

13 0ZG0-: gabbro, spots, level, mean =, MSWD = Note: *Radiogenic lead. Isotopic ratios and ages were corrected by common lead, following the methods reported by Andersen (00).

14 Note : LA ICPMS zircon U Pb dating Zircons were separated by heavy-liquid and magnetic methods. Cathodoluminescence images were used to check the internal structures of individual zircon grains and to select positions for analyses. Zircon U-Pb dating was performed using laser ablation microprobe multicollector inductively coupled plasma mass spectrometry (LA-ICPMS) at the Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China. The spot diameter for each analysis is 0 μm, and data were collected during 0 s of ablation after approximately 0 s of background counting. U-Th-Pb isotope ratios were measured relative to the standard material (NIST0) with a recommended 0 Pb/ U age of 0. ± 0. (Wiedenbeck et al., ) and were calculated using the GLITTER.0 (GEMOC) software (Jackson et al., 00). Common lead was corrected using the common lead correction function proposed by Anderson (00). The plotting of concordia diagrams, age spectra, and age calculations were made using ISOPLOT (version.0) (Ludwig, 00). The detailed analytical technique was described in Xie et al. (00). Uncertainties on individual analyses are reported at the -sigma level; mean ages for pooled 0 Pb/ U results are reported at the -sigma level. References cited: Anderson, T., 00, Correction of common lead in U-Pb analyses that do not report 0 Pb: Chemical Geology, v., p. -. Jackson, S.E., Pearson, N.J., Griffin, W.L., and Belousova, E.A., 00, The application of laser ablation-inductively coupled plasma-mass spectrometry (LA-ICPMS) to in situ U Pb zircon geochronology: Chemical Geology, v., p. -. Ludwig, K.R., 00, ISOPLOT.0: A Geochronological Toolkit for Microsoft Excel: Berkeley Geochronology Center Special Publication, v., p.. Wiedenbeck, M., Alle, P., Corfu, F., Griffin, W.L., Meier, M., Oberli, F., von Quadt, A., Roddick, J.C., and Spiegel, W.,, Three natural zircon standards for U-Th-Pb, Lu-Hf, trace element and REE analyses: Geostandards. Newsletter Journal of Geostandar, v., p. -. Xie, L.W., Zhang, Y.B., Zhang, H.H., Sun, J.F., and Wu, F.Y., 00, In situ simultaneous determination of trace elements, U-Pb and Lu-Hf isotopes in zircon and baddeleyite: Chinese Science Bulletin, v., p. -.

Cloudland gneisses, Mars Hill terrane, NC-TN: New SHRIMP U-Pb ages for detrital zircon and. monazite

GSA DATA REPOSITORY 2013302 J.N. Aleinikoff et al. Late Mesoproterozoic (ca. 1.0 Ga) deposition of protoliths of the high grade Carvers Gap and Cloudland gneisses, Mars Hill terrane, NC-TN: New SHRIMP