Table 1 1 U-Pb U-Pb isotopic determinations of zircon in quartz diorite from the Jiarongjiandegongka intrusive rocks 1 Qh al pal - Qp 3 - TB

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1 Sedimentary Geology and Tethyan Geology Vol. 31 No. 3 Setp Rb K Ba Th Sr Nb Ta Ti P P A ~ cm 15 30cm 10 ~ 20mm 100 ~ 200m NW-SE ~ 3 8cm % ~ 1% 132Ma U-Pb

1 A 1990 1 20 1 25 40 ~ 50 2 5cm 15 30cm 10 ~ 20mm 100 ~ 200m 1 - - NW-SE 3

2 Table 1 1 U-Pb U-Pb isotopic determinations of zircon in quartz diorite from the Jiarongjiandegongka intrusive rocks 1 Qh al pal - Qp 3 - TB b 3 - TB 3 a - T 3 K - K 1 γδ J - K 1 δi J - K 1 δο J - YZS - BNS - - XJS - - KQS - - Fig. 1 Simplified geological map of the Jiarongjiandegongka region Qh al pal = Quaternary alluvial deposits Qp 3 = Quaternary pluvial and alluvial deposits TB c 3 = upper member of the Banyan Formation of the Bayan Har Group TB b 3 = middle member of the Banyan Formation of the Bayan Har Group TB a 3 = lower member of the Banyan Formation of the Bayan Har Group T 3 K = Kenan Group K 1 γδ J = Jiarongjiandegongka granodiorite. K 1 δi J = Jiarongjiandegongka tonalite K 1 δo J = Jiarongjiandegongka quartz diorite YZS = Yarlung Zangbo suture zone BNS = Bangong Lake-Nujiang suture zone XJS = Xijir Ulan-Jinshajiang suture zone KQS = Kunlun-Qinling suture zone 1. 1 NW-SE 2 SiO % ~ % 0. 9km km 2 SiO % ~ % / % ALK = 3. 96% ~ 4. 29% 4. 12% An = 32 65% ~ 69% 5% ~ 10% 5% 34. 5km km km km 2 An = 28 ~ 33 60% ~ 63% 15% ~ 18% 0% ~ 1% 8% ~ 10% 5% ~ 8% / / 1. 3 TB c km km 2 NW-SE 3. 4km 2 An = 29 ~ 30 55% ~ 59% 7% ~ 9% 20% ~ 23% 5% ~ 7% 3% ~ 4% 2 Na 2 O > K 2 O σ = ~ A /CNK = ~ SiO 2 ~ 12% 8% ~ 10% % ~ % % ALK = ~ 5. 49% 4. 79% Na 2 O > K 2 O σ = ~ A /CNK = ~ SiO % ~ % % ALK NW - SE = 4. 56%

1 Simplified geological map of the Jiarongjiandegongka region Qh al pal = Quaternary alluvial deposits Qp 3 = Quaternary pluvial and alluvial deposits TB c 3 = upper member of the Banyan Formation of

3 90 2 Table 2 2 /% Chemical compositions % of the Jiarongjiandegongka intrusive rocks ~ 5. 49% 5. 22% Na 2 O > K 2 O σ = ~ A /CNK = ~ SiO 2 SiO 2 - Na 2 O + K 2 O SiO 2 - K 2 O 2 2 SiO 2 -K 2 O Fig.2 SiO 2 -K 2 O diagram for the Jiarongjiandegongka intrusive rocks = granodiorite = tonalite = quartz diorite

99 SiO 2 SiO 2 - Na 2 O + K 2 O SiO 2 - K 2 O 2 2 SiO 2 -K 2 O 3 3. 1 Fig.

4 = ~ Eu - 3 La /Yb n = ~ La /Yb n = δEu = ~ Eu ~ δeu = ~ Eu - La /Yb n = ~ δeu δeu Table / 10-6 REE contents 10-6 in the Jiarongjiandegongka intrusive rocks 4 MORB 3 Leedy MORB Beviens et al Fig. 3 Chondrite-normalized REE distribution patterns for the Fig. 4 MORB-normalized trace element spidergrams for the Jiarongjiandegongka intrusive rocks chondrite values from Jiarongjiandegongka intrusive rocks MORB values from Beviens Leedy et al Rb / Sr > 0. 5 Nb /Ta = ~ MORB Rb Green La /Nb = ~ K Ba Th Sr Nb Ta Ti P P Ti Rb /Sr = ~

3 Chondrite-normalized REE distribution patterns for the Fig.

5 92 2 Table 4 4 / 10-6 Trace element contents 10-6 in the Jiarongjiandegongka intrusive rocks 4 Sr Nd Pb Sr Nd 5 εsr t 110 εnd t ~ εsr t ~ εnd t -εsr t 5 Ⅳ Table 5 5 Nd Sr Nd and Sr isotopic compositions in the Jiarongjiandegongka intrusive rocks 6 Pb β- γ 6 3a 5 5 εnd t -εsr t Fig. 5 εnd t vs. εsr t diagram for the Jiarongjiandegongka intrusive rocks SiO % ~ % A / CNK = ~ ALK = ~ 5. 49% Na 2 O > K 2 O Rb K Ba Th Nb /Ta = ~ Green

7 εnd t -εsr t 5 Ⅳ Table 5 5 Nd Sr Nd and Sr isotopic compositions in the Jiarongjiandegongka intrusive rocks 6 Pb β- γ 6 3a 5 5 εnd

6 Table 6 6 Pb Pb isotopic compositions in the Jiarongjiandegongka intrusive rocks 6 Pb β - γ a ORG 3b Fig. 7 Rb vs. Y + Nb discriminant diagram after Pearce et Fig. 6 β vs. γ diagram for Pb isotopes 1 = mantle-derived lead 2 = upper crust-derived lead 3 = mixed upper crust- and mantle-derived lead 3a = magmatism 3b = sedimentation 4 = chemical-sedimentary lead 5 = submarine hydrothermal lead 6 = mesometamorphic to hypometamorphic lead 7 = hypometamorphic lower crust-derived lead 8 = orogenic lead 9 = upper crust-derived lead from old shale 10 = retrograde metamorphic lead La /Nb = ~ εnd t ~ Sr /86Sr i ~ Pb β - γ 6 8 Rb - Yb + Ta VAG WPG 3a ORG Rb-Y + Nb Rb-Yb + Ta Fig. 8 Rb vs. Yb + Ta discriminant diagram 7 8 VAG = volcanic arc granites WPG = within plate granites S- COLG = syn-collision granites ORG = ocean ridge granites 7 Rb - Y + Nb VAG WPG S - COLG al VAG = volcanic arc granites WPG = within plate granites S-COLG = syn-collision granites ORG = ocean ridge granites S - COLG

γ diagram for Pb isotopes 1 = mantle-derived lead 2 = upper crust-derived lead 3 = mixed upper crust- and mantle-derived lead 3a = magmatism 3b = sedimentation 4 = chemical-sedimentary lead 5 =

7 Rb K Ba Th Sr Nb Ta Ti P 2-4 εnd t ~ Sr /86Sr i ~ P - T 2 Bird GREEN T H. Significance of Nb /Ta as an indicator of geochemical processes in the crust-mantle system J. Chem. 4 Geol A 2. M M M BIRD P. Initiation of intracontinental subduction in the Himalaya J. J. Geophys. Res J Geochemistry and tectonic setting of the Jiarongjiandegongka intrusive rocks in Qumarleb Qinghai BAI Yun-shan NIU Zhi-jun DUAN Qi-fa TANG Chao-yang LI Li PANG Ying-chun Wuhan Center China Geological Survey Wuhan Hubei China Abstract The intrusive sequences in Jiarongjiandegongka Qinghai consist of quartz diorite tonalite granodiorite and syenogranite. The lithochemical compositions display the evolution from intermediate basic to acidic rocks and the magmas are rich in silica and alkali. The geochemical signatures are characterized by the enrichment of LREE enrichment of large ion lithophile elements such as Rb K Ba and Th slight depletion of Sr Nb and Ta and strongly depletion of Ti and P. The tectonic setting of the Jiarongjiandegongka intrusive rocks are assigned to syn-collision granites and may be traced back to the Early Cretaceous. Key words Jiarongjiandegongka intrusive sequence tectonic setting intrusive rock southern Qinghai

Initiation of intracontinental subduction in the Himalaya J. J. Geophys. Res. 1987 83 4975-4978. 6. J. 2001 75 4 484-497.

NE NW NE NW 6 NE NW NE ~ 85 1 ~ 4 NW NE 702 NE NW 1 NE30 ~ 50 SE 50 ~ 60 1a I II I 73 m 3. 5 m g /t II 62 m 60 ~ 100

NE NW NE NW 6 NE NW NE ~ 85 1 ~ 4 NW NE 702 NE NW 1 NE30 ~ 50 SE 50 ~ 60 1a I II I 73 m 3. 5 m g /t II 62 m 60 ~ 100 34 2 2015 6 GLOBAL GEOLOGY Vol. 34 No. 2 Jun. 2015 1004 5589 2015 02 0385 11 1 1 2 2 1 1 1. 130061 2. 702 157021 σ < 3. 3 Rb Ba K Pb LILE Nb Ta P Ti HFSE LREE HREE Nb /Ta 14. 7 Zr /Hf 26. 23 ~ 38. 37 P618.