GSA DATA REPOSITORY

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1 GSA DATA REPOSITORY Chen et al. ANALITICAL METHODS Microprobe analysis Microprobe analyses of minerals were done on a JEOL Superprobe JXA 8100 at the Key Laboratory of Orogenic Belts and Crustal Evolution, Peking University, using an accelerating voltage of 15 kv, beam current A and spot diameter of 1 m. Microprobe data were provided in Table DR1. Major and trace element analysis Major and trace elements of whole rocks were measured at the China University of Geosciences (Beijing) by the XRF (using fused glass disks) and ICP-MS (Elan 6100 DRC, after acid digestion of samples in Teflon bombs) methods, respectively. Analyses of United States Geological Survey rock standards (BCR-2, BHVO-1 and AGV-1) indicate precision and accuracy better than 5% for major elements and 10% for trace elements and REEs. Sr Nd isotopes Nd-Sr isotopic analyses were performed on a Thermo-Finnigan TRITON at the Tianjin Institute of Geology and Mineral Resources, in negative ion detection mode, equipped with an oxygen gas leak valve, nine Faraday cups, and an ion counting multiplier. Samples were dissolved using acid (HF + HClO 4 ) in sealed Savillex beakers on a hot plate for one week. Separation of Rb, Sr and light REE was done through a cation-exchange column (packed with Bio-Rad AG50Wx8 resin). Sm and Nd were further purified using a second cation-exchange column, conditioned and eluded with dilute HCl. 87 Sr/ 86 Sr ratios were normalized against 86 Sr/ 88 Sr = Nd/ 144 Nd ratios were normalized against 146 Nd/ 144 Nd = The La Jolla standard measured during the course of analyses gave an average 143 Nd/ 144 Nd of ± 5 (2, n=15), and BCR-2 gives 143 Nd/ 144 Nd = ± 4. NBS-987 gave 87 Sr/ 86 Sr = ± 16 (2, n = 5). Re-Os isotopes Rhenium and Os isotope analyses were performed on a ThermoFinnigan TRITON R in negative ion detection mode at Japan Agency for Marine-Earth Science and Technology (JAMSTEC) using the Carius tube digestion method (Shirey and Walker, 1995), combined with carbon tetrachloride extraction and microdistillation (Pearson and Woodland, 2000). One to three grams of sample powder together with 185 Re and 190 Os spike solutions were digested in inverse aqua regia (ca. 10 ml) in Carius tubes at 240 o C for 24 hours. Os was separated by carbon tetrachloride extraction from the aqua regia fraction and was back-extracted into 9N HBr, and further purified by microdistillation. Re was separated from the aqueous phase after Os extraction using Muromac AG1-X8 anion exchange resin ( mesh). Osmium isotopic compositions were measured on an ion counting detector. Instrumental mass fractionation of Os was corrected by normalizing the measured 192 Os/ 188 Os ratio to Rhenium isotopes were measured using a total evaporation technique (Suzuki et al., 2004), which allows us to more precisely determine Re isotope ratios relative to conventional measurements, even for small amounts of sample. Both Re and Os were corrected for blanks. Total blank levels were 8 ± 2 and

2 3 ± 2 pg for Re and Os, respectively, and the blank 187 Os/ 188 Os ratio was ± Precision of 187 Os/ 188 Os measurements, based on analysis of an in-house standard over a period of several months, was better than 0.4% (2 standard deviations). FIGURE CAPTION FOR FIGURE DR1 Figure DR1. Primitive mantle normalized multi-element spidergrams for the Jinling- Tietongou high-mg dioritic rocks and the adakitic rocks from the Dabie orogen interpreted to be associated with an eclogitic source in a thickened lower crust (He et al., 2011). The Jinlingtietongou dioritic rocks show geochemical features basically similar to that of the Dabie adakitic rocks, except that the latter show a bit lower heavy REEs and Y abundance. We suggest that this is attributable to a stronger fractionation of ferromagnesian phases in the adakitic rocks from the Dabie orogen, which would deplete the residual magma in HREEs and Y, and raise the Sr abundance and Sr/Y ratios at the same time (see the modeling in Figure 3B), NOT as a result of equilibration with a eclogitic source (He et al., 2011). This is consistent with the fact that the adakitic rocks from Dabie region show silica contents (65-69%) significantly higher than those of the Jinling-Tietongou high-mg dioritic rocks (53-63%). Primitive mantle values are from Sun and McDonough (1989). REFERENCES CITED Pearson, D.G., and Woodland, S.J., 2000, Solvent extraction/anion exchange separation and determination of PGEs (Os, Ir, Pt, Pd, Ru) and Re-Os isotopes in geological samples by isotope dilution ICP-MS: Chemical Geology, v. 165, p Shirey, S.B., and Walker, R.J., 1995, Carius tube digestion for low-blank rhenium-osmium analysis: Anal Chemistry, v. 67, p Suzuki, K., Miyata, Y., and Kanazawa, N., 2004, Precise Re isotope ratio measurements by negative thermal ionization mass spectrometry (NTI-MS) using total evaporation technique: International Journal of Mass Spectrometry, v. 235, p He, Y.S., Li, S.G., Hoefs, J., Huang, F., Liu, S.A., and Hou, Z.H., 2011, Post-collisional granitoids from the Dabie orogen: New evidence for partial melting of a thickened continental crust: Geochimica et Cosmochimica Acta, v. 75, p Sun, S.S., and McDonough, W.F., 1989, Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes, in Saunders, A.D., and Norry, M.J., eds., Magmatism in the Ocean Basins, Geological Society, London, Special Publications 42, pp

3 3 Table DR1. Microprobe analyses of plagioclase, clinopyroxene, orthopyroxene, olivine and hornblende spot# mineral SiO 2 Al 2 O 3 CaO Na 2 O K 2 O Si Al Ca Na K An JL-5.1 plag Fig.3a JL-5.2 plag JL-5.3 plag JL-5.4 plag JL-5.5 plag JL-5.6 plag JL-5.8 plag JL-5.9 plag JL-5.10 plag JL-5.11 plag JL-5.12 plag JL-5.13 plag JL-5.14 plag TT-7.1 plag Fig.3b TT-7.2 plag TT-7.3 plag TT-7.4 plag TT-7.5 plag TT-7.6 plag TT-7.15 plag TT-7.7 plag TT-7.8 plag TT-7.9 plag TT-7.10 plag TT-7.11 plag TT-7.12 plag TT-7.13 plag TT-7.14 plag spot# mineral SiO 2 TiO 2 Al 2 O 3 Fe 2 O 3 FeO MgO CaO Na 2 O Mg# spot# TT Cpx Fig.3c TT Cpx TT Cpx TT Cpx TT Cpx TT Cpx TT Cpx TT Cpx TT Cpx TT Cpx TT Cpx

4 4 TT Cpx TT Cpx TT Cpx TT Cpx TT Opx Fig.3d TT Opx TT Opx TT Cpx TT Cpx TT Cpx TT Cpx TT Cpx JL Opx Fig.3e JL Opx JL Opx JL Opx JL Opx JL Hb JL Hb JL Hb JL Hb TT7-6.2 Ol Fig.3f TT7-6.3 Ol TT7-6.4 Ol Note: plag-plagioclase; cpx-clinopyroxene; opx-orthopyroxene; hb-hornblende; ol-olivine Mg# = molar 100 Mg/(Mg+Fe).

5 5 Table DR2. Major and trace elements of the Jinling-Tietongou high-mg diorites Sample TT-1 TT-3 TT-7 TT-8 TT-12 TT-20 TT-23 TT-26 TT-27 TT-28 TT-31 TT-35 TT-36 Rock type GD D GD GD D D D QD D D D D D SiO TiO Al 2 O TFeO CaO MgO MnO K 2 O Na 2 O P 2 O LOI Total Mg# Rb Sr Ba Y Zr Hf Pb Th U Nb Ta Ga V Cr Co Ni La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb

6 6 Lu Sr/Y Eu/Eu* (La/Yb) N Sample TT-26B JL-1 JL-10 JL-24 JL-25 JL-27 JL-19B JL-21B JL-29B JL-36B JL-38B JL-40B JL-41 rock type GD GD D QD QD QD D D D GD D D D SiO TiO Al 2 O TFeO CaO MgO MnO K 2 O Na 2 O P 2 O LOI Total Mg# Rb Sr Ba Y Zr Hf Pb Th U Nb Ta Ga V Cr Co Ni La Ce Pr Nd Sm Eu Gd Tb Dy Ho

7 7 Er Tm Yb Lu Sr/Y Eu/Eu* (La/Yb) N Note: Major oxides are reported in weight per cent (wt%), and trace elements in parts per million (ppm); TFeO, total iron as FeO; Mg#, molar Mg/(Mg+Fe); D-diorite; GD-gabbroic diorite; QD-quartz diorite. Table DR3. Sr-Nd isotope compositions of the Jinling-Tietongou high-mg diorites Sample [Rb] [Sr] No. (ppm) (ppm) 87 Rb/ 87 Sr/ 2sm I Sr [Sm] [Nd] 86 Sr (130 Ma) (ppm) (ppm) 147 Sm/ 144 Nd 143 Nd/ 2sm e Nd (T) 144 Nd (130 Ma) 86 Sr TT TT TT TT TT TT TT TT TT TT TT TT TT TT26B JL JL JL JL JL JL19B JL21B JL29B JL36B JL38B JL40B JL Note: Initial Sr and Nd isotopic ratios were calculated at t = 130 Ma.

8 8 Table DR4. Re-Os isotopic data of the Jinling-Tietongou diorites and TTG gneisses Sample # rock Re (ppt) 2s Os (ppt) 2s 187 Re/ 188 Os 2s 187 Os/ 188 Os 2s (187 Os/ 188 Os) i JL-1 GD JL-10 D JL-40B D TT-1 GD TT-7 GD TT-8 GD TT-17 GD TT-26 D TT-26B GD ##### MJ-6 TTG Note: The parameters used in calculation are: l Re = /year, ( 187 Re/ 188 Os) Chond = , and ( 187 Os/ 188 Os) Chond,0 = D-diorite; GD-gabbroic diorite; QD-quartz diorite

9 Figure DR1