Zircon U-Pb chronology, geochemistry and Lu-Hf isotope constraints on genesis of monzonitic granite from Harizha area in eastern section of East Kunlun region
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摘要
The Harizha area is located in the eastern section of East Kunlun orogenic belt. The petrology, the zircon LA-ICP-MS U-Pb chronology and the petrogeochemistry of the monzonitic granite in the area were studied. The results show that the formation age of the monzonitic granite in the Harizha area is 237.4±1.4 Ma, which belongs to Middle Triassic. The content of SiO_2 in the rock is 61.29%--63.30%,(K_2O+Na_2O) is 5.41%--5.84%, Al_2O_3 is 14.80%--15.99%, the Mg~# value is 46.33--48.33, and the aluminum saturation index A/CNK is 0.87--0.91. Therefore, it can be concluded that the rock belongs to the I-type granite of quasi-aluminous high potassium Ca-alkaline series. The total REE content of the rock is 118.82×10~(-6)--164.54×10~(-6), and the La/Yb ratios range from 7.77 to 10.13. Meanwhile, the rock does not show obvious Eu anomalies(δEu=0.61--0.75) and is characterized by enrichment of LREE and LILE such as Rb and K, relative depletion of HREE and HFSE such as Nb, Ti and Ta. Zircon Hf isotopic dating exhibits that the average ε_(Hf)(t) is-2.4 and the average of two-stage model age(t_(DM2)) is 1 417 Ma, indicating that the source rocks are mainly crustal materials. It can be concluded from research findings and regional geological structural analysis that the monzonitic granite in the Harizha area originated from partial melting of the Mesoproterozoic mafic lower crust in the later stage of the subduction of the Paleo-Tethys Ocean.
The Harizha area is located in the eastern section of East Kunlun orogenic belt. The petrology, the zircon LA-ICP-MS U-Pb chronology and the petrogeochemistry of the monzonitic granite in the area were studied. The results show that the formation age of the monzonitic granite in the Harizha area is 237.4±1.4 Ma, which belongs to Middle Triassic. The content of SiO_2 in the rock is 61.29%--63.30%,(K_2O+Na_2O) is 5.41%--5.84%, Al_2O_3 is 14.80%--15.99%, the Mg~# value is 46.33--48.33, and the aluminum saturation index A/CNK is 0.87--0.91. Therefore, it can be concluded that the rock belongs to the I-type granite of quasi-aluminous high potassium Ca-alkaline series. The total REE content of the rock is 118.82×10~(-6)--164.54×10~(-6), and the La/Yb ratios range from 7.77 to 10.13. Meanwhile, the rock does not show obvious Eu anomalies(δEu=0.61--0.75) and is characterized by enrichment of LREE and LILE such as Rb and K, relative depletion of HREE and HFSE such as Nb, Ti and Ta. Zircon Hf isotopic dating exhibits that the average ε_(Hf)(t) is-2.4 and the average of two-stage model age(t_(DM2)) is 1 417 Ma, indicating that the source rocks are mainly crustal materials. It can be concluded from research findings and regional geological structural analysis that the monzonitic granite in the Harizha area originated from partial melting of the Mesoproterozoic mafic lower crust in the later stage of the subduction of the Paleo-Tethys Ocean.
The Harizha area is located in the eastern section of East Kunlun orogenic belt. The petrology, the zircon LA-ICP-MS U-Pb chronology and the petrogeochemistry of the monzonitic granite in the area were studied. The results show that the formation age of the monzonitic granite in the Harizha area is 237.4±1.4 Ma, which belongs to Middle Triassic. The content of SiO_2 in the rock is 61.29%--63.30%,(K_2O+Na_2O) is 5.41%--5.84%, Al_2O_3 is 14.80%--15.99%, the Mg~# value is 46.33--48.33, and the aluminum saturation index A/CNK is 0.87--0.91. Therefore, it can be concluded that the rock belongs to the I-type granite of quasi-aluminous high potassium Ca-alkaline series. The total REE content of the rock is 118.82×10~(-6)--164.54×10~(-6), and the La/Yb ratios range from 7.77 to 10.13. Meanwhile, the rock does not show obvious Eu anomalies(δEu=0.61--0.75) and is characterized by enrichment of LREE and LILE such as Rb and K, relative depletion of HREE and HFSE such as Nb, Ti and Ta. Zircon Hf isotopic dating exhibits that the average ε_(Hf)(t) is-2.4 and the average of two-stage model age(t_(DM2)) is 1 417 Ma, indicating that the source rocks are mainly crustal materials. It can be concluded from research findings and regional geological structural analysis that the monzonitic granite in the Harizha area originated from partial melting of the Mesoproterozoic mafic lower crust in the later stage of the subduction of the Paleo-Tethys Ocean.
引文
Amelin Y, Lee D C, Halliday A N. 2000. Early-Middle Archean crustal evolution deduced from Lu-Hf and U-Pb isotope studies of single zircon grains. Geochimica et Cosmochimica Acta, 64: 4205-4225.
Anderson T. 2002. Correction of common lead in U-Pb analyses that do not report 204Pb. Chemical Geology, 192(1/2): 59-79.
Belousova E A, Griffin W L, O'Reilly S Y, et al. 2002. Igneous zircon: trace element composition as an indicator of source rock type. Contributions to Mineralogy and Petrology, 143(5): 602-622.
Chappell B W. 1999. Aluminium saturation in I- and S-type granites and the characterization of fractionated hapogranites. Lithos, 46: 535-551.
Chen G C, Pei X Z, Li R B, et al. 2013. Late Triassic magma mixing in the East Kunlun orogenic belt: a case study of Helegang Xilikete granodiorites. Geology in China, 40: 1044-1065. (in Chinese with English abstract)
Chen G C. 2011. A study on petrogenesis and geological significance of the granitic rocks in southern margin of the East Kunlun region during Indosinian: master's degree thesis. Xi'an: Chang'an University. (in Chinese with English abstract)
Chen G C. 2014. Petrology, genesis and geological significance of Late Paleozoic--Early Mesozoic granitoids in East Kunlun orogen: doctor's degree thesis. Xi'an: Chang'an University. (in Chinese with English abstract)
Chen G C, Pei X Z, Li R B, et al. 2018. Age and lithogenesis of Keri syenogranite from eastern part of East Kunlun orogenic belt: constraint on the Middle Triassic tectonic evolution of East Kunlun. Acta Petrologica Sinica, 34(3): 567-585. (in Chinese with English abstract)
Chen G C, Pei X Z, Li R B, et al. 2018. Triassic magma mixing and mingling at the eastern section of Eastern Kunlun: a case study from Xiangjiananshan granitic batholith. Acta Petrologica Sinica, 34(8): 2441-2480. (in Chinese with English abstract)
Chen J J, Wei J H, Fu L B, et al. 2017. Multiple sources of the Early Mesozoic Gouli batholith, Eastern Kunlun orogenic belt, northern Tibetan Plateau: linking continental crustal growth with oceanic subduction. Lithos, 292: 161-178.
Chen S J, Li RS, Ji W H, et al. 2010. The Permian lithofacies paleogeographic characteristics and basin-mountain conversion in the Kunlun orogenic belt. Geology in China, 37(2): 374-393. (in Chinese with English abstract).
Defant M J, Drummond M S.1990. Derivation of some modern arc magmas by melting of young subduction lithosphere. Nature, 347: 662-665.
Griffin W L, Wang X, Jackson S E, et al. 2002. Zircon chemistry and magma mixing, SE China: in-situ analysis of Hf isotopes, Tonglu and Pingtan igneous complexes. Lithos, 61: 237-269.
Guo X Z, Jia Q Z, Kong H L, et al. 2016. Ages, genesis and geological significance of Harizha quartz diorite in the east section of East Kunlun mountains. Geological Science and Technology Information, 35(5): 18-26. (in Chinese)
Guo Z F, Deng J F, Xu Z Q, et al. 1998. Late Palaeozoic-Mesozoic intracontinental orogenic process andintermedate-acidic igneous rocks from the Eastern Kunlun Mountains of northwestern China. Geoscience, 12(3): 344-352. (in Chinese with English abstract)
Huang H, Niu Y L, Nowell G, et al. 2014. Geochemical constraints on the petrogenesis of granitoids in the East Kunlun orogenic belt, northern Tibetan Plateau: implications for continental crust growth through syn-collisional felsic magmatism. Chemical Geology, 370: 1-18.
Jiang C F, Yang J S, Fen B G. 1992. Opening-closing tectonics of the Kunlun Mountain. Beijing: Geological Publishing House, 183-217. (in Chinese)
Jiang C F, Wang Z Q, Li M T. 2000. Opening-closing tectonics of the central orogenic belt. Beijing: Geological Publishing House,1-154. (in Chinese)
Li R B. 2012. Research on the Late Paleozoic--Early Mesozoic orogeny in East Kunlun orogen: doctor's degree thesis. Xi'an: Chang'an University. (in Chinese with English abstract)
Li R B, Pei X Z, Li Z C, et al. 2018. Paleo-Tethys Ocean subduction in eastern section of East Kunlun orogen: evidence from the geochronology and geochemistry of the Wutuo pluton. Acta Petrologica Sinica, 34(11): 3399-3421. (in Chinese with English abstract)
Liu H T. 2005. Petrology, geochemistry and geochronology of Late Triassic volcanics, Kunlun orogenic belt, western China: implications for tectonic setting and petrogenesis. Geochemical Journal, 39(1): 1-20.
Liu Y S, Hu Z C, Gao S, et al. 2008. In situ analysis of major and trace elements anhydrous minerals by LA-ICP-MS without applying an internal standards. Chemical Geology, 257(1/2): 34-43.
Liu Y S, Hu Z C, Gao S, et al. 2010. Continental and oceanic crust recycling-induced melt-periotite interactions in the Trans-North China orogen:U-Pb dating,Hf isotopes and trace elements in zircons from mantle xenoliths. Journal of Petrology, 51(1/2): 537-571.
Luo Z H, Deng J F, Cao Y Q, et al. 1999. On Late Paleozoic-Early Mesozoic volcanism and regional tectonic evolution of Eastern Kunlun, Qinghai Province. Geoscience, 13(1): 51-56. (in Chinese with English abstract)
Ludwig K R. 2003. User's manual for Isoplot 3.00: a geochronological toolkit for Microsoft Excel. Berkeley: Berkeley Geochronology Center Special Publication, 1-70.
Ma C Q,Xiong F H,Yin S,et al. 2015. Intensity and cyclicity of orogenic magmatism: an example from a Paleo-Tethyan granitoid batholith, eastern Kunlun, northern Qinghai--Tibetan Plateau. Acta Petrologica Sinica, 31(12): 3555-3568. (in Chinese with English abstract)
Mo X X, Luo Z H, Deng J F, et al. 2007. Granitoids and crustal growth and in the East-Kunlun orogenic belt. Geological Journal of China Universities, 13(3): 403-414. (in Chinese with English abstract).
Richards J P. 2003. Tectono-magmatic precursors for porphyry Cu-(Mo-Au) deposit formation. Economic Geology, 98(8):1515-1533.
Saunders A D, Norry M J, Tarney J. 1998. Origin of MORE and chemically depleted mantle reservoirs: trace element constraints. Journal of Petrology, Special Volume (1): 415-445.
Song B, Zhang Y H, Wan Y S, et al. 2002. Mount making and procedure of the SHRIMP dating. Geological Review, 48(Suppl.): 26-30. (in Chinese with English abstract)
Song Z B, Zhang Y L, Chen X Y, et al. 2013.Geochemical characteristics of Harizha granite diorite-porphyry in East Kunlun and their geological implications. Mineral Deposits, 32(1): 157-168. (in Chinese with English abstract)
Sun F Y, Li B L, Ding Q F. 2009. Report of major ore-prospecting problems study in East Kunlun metallogenic belt. Changchun: Institute of Geological Survey of Jilin University. (in Chinese)
Tang J, Ren J Q, Wang L, et al. 2008. Comprehensive investigation report of 1:50 000 regional mineral geology, sediment geochemistry and high precision magnetic survey in Chahan Wusu River area, Dulan County, Qinghai Province. Xining: Institute of Geological Survey of Qinghai Province. (in Chinese)
Taylor S R, McLennan S M. 1995. Layered igneous rocks. San Francisco: Freeman WH & CO, 150-203.
Vervoort J D, Patchett P J. 1996. Behavior of hafnium and neodymium isotopes in the crust: constraints from Precambrian crustally derived granites. Geochimica et Cosmochimica Acta, 60: 3717-3733.
Whalen J B, Carrie K L, Chappell B W. 1987. A-type granites: geochemical characteristics, discrimination and petrogenesis. Contribution to Mineralogy and Petrology, 95: 407-419.
Wolf M B, Wyllie P J. 1994. Dehydration-melting of amphibolite at 10 kbar: the effects of temperature and Time. Contributions to Mineralogy and Petrology, 115(4): 369-383.
Wu F Y, Yang Y H, Xie L W, et al. 2006. Hf isotopic compositions of the standard zircons and baddeleyites used in U-Pb geochronology. Chemical Geology, 234:105-126.
Wu F Y, Li X H, Zheng Y F, et al. 2007. Lu-Hf isotopic systematics and their applications in petrology. Acta Petrologica Sinica, 23(2):185-220. (in Chinese with English abstract)
Xiong X L, Adam J, Green T H. 2005. Rutile stability and rutile/melt HFSE partitioning during partial melting of hydrous basalt: implications for TTG genesis. Chemical Geology, 218: 339-359.
Xu Z Q, Yang J S, Li W C, et al. 2013. Paleo-Tethys system and accretionary orogen in the Tibet Plateau. Acta Petrologica Sinica, 29(6): 1847-1860. (in Chinese with English abstract)
Yang H L, Gao S, Liu X M, et al. 2004. Accurate U-Pb age and trace element determinations of zircon by laser ablation-inductively coupled plasma-mass spectrometry. Geostandards and Geoanalytical Research, 28(3): 353-370.
Yang J S, Robinson P T, Jiang C F, et al.1996. Ophiolites of the Kunlun Mountains, China and their tectonic implications. Tectonophysics, 258(1): 215-231.
Yang J S, Xu Z Q, Li H B, et al. 2005. The Paleo-Tethyan volcanism and plate tectonic regime in the A'nyemaqen region of East Kunlun, northern Tibet Plateau. Acta Petrologica et Mineralogica, 24(5): 369-380. (in Chinese with English abstract)
Yin H F, Zhang K X. 1998. Evolution and characteristics of the central orogenic belt. Earth Science, 23(5): 438-442.(in Chinese with English abstract)
Yuan C,Sun M,Xiao W J,et al. 2009. Garnet-bearing tonalitic porphyry from East Kunlun, northeast Tibetan Plateau: Implications for adakite and magmas from the mashzone. International Journal of Earth Sciences, 98(6): 1489-1510.
Zhang Q, Wang Y, Li C D, et al. 2006. Granitite classification on the basis of Sr and Yb contents and its implications. Acta Petrologica Sinica, 22(9): 2249-2269. (in Chinese with English abstract)
Anderson T. 2002. Correction of common lead in U-Pb analyses that do not report 204Pb. Chemical Geology, 192(1/2): 59-79.
Belousova E A, Griffin W L, O'Reilly S Y, et al. 2002. Igneous zircon: trace element composition as an indicator of source rock type. Contributions to Mineralogy and Petrology, 143(5): 602-622.
Chappell B W. 1999. Aluminium saturation in I- and S-type granites and the characterization of fractionated hapogranites. Lithos, 46: 535-551.
Chen G C, Pei X Z, Li R B, et al. 2013. Late Triassic magma mixing in the East Kunlun orogenic belt: a case study of Helegang Xilikete granodiorites. Geology in China, 40: 1044-1065. (in Chinese with English abstract)
Chen G C. 2011. A study on petrogenesis and geological significance of the granitic rocks in southern margin of the East Kunlun region during Indosinian: master's degree thesis. Xi'an: Chang'an University. (in Chinese with English abstract)
Chen G C. 2014. Petrology, genesis and geological significance of Late Paleozoic--Early Mesozoic granitoids in East Kunlun orogen: doctor's degree thesis. Xi'an: Chang'an University. (in Chinese with English abstract)
Chen G C, Pei X Z, Li R B, et al. 2018. Age and lithogenesis of Keri syenogranite from eastern part of East Kunlun orogenic belt: constraint on the Middle Triassic tectonic evolution of East Kunlun. Acta Petrologica Sinica, 34(3): 567-585. (in Chinese with English abstract)
Chen G C, Pei X Z, Li R B, et al. 2018. Triassic magma mixing and mingling at the eastern section of Eastern Kunlun: a case study from Xiangjiananshan granitic batholith. Acta Petrologica Sinica, 34(8): 2441-2480. (in Chinese with English abstract)
Chen J J, Wei J H, Fu L B, et al. 2017. Multiple sources of the Early Mesozoic Gouli batholith, Eastern Kunlun orogenic belt, northern Tibetan Plateau: linking continental crustal growth with oceanic subduction. Lithos, 292: 161-178.
Chen S J, Li RS, Ji W H, et al. 2010. The Permian lithofacies paleogeographic characteristics and basin-mountain conversion in the Kunlun orogenic belt. Geology in China, 37(2): 374-393. (in Chinese with English abstract).
Defant M J, Drummond M S.1990. Derivation of some modern arc magmas by melting of young subduction lithosphere. Nature, 347: 662-665.
Griffin W L, Wang X, Jackson S E, et al. 2002. Zircon chemistry and magma mixing, SE China: in-situ analysis of Hf isotopes, Tonglu and Pingtan igneous complexes. Lithos, 61: 237-269.
Guo X Z, Jia Q Z, Kong H L, et al. 2016. Ages, genesis and geological significance of Harizha quartz diorite in the east section of East Kunlun mountains. Geological Science and Technology Information, 35(5): 18-26. (in Chinese)
Guo Z F, Deng J F, Xu Z Q, et al. 1998. Late Palaeozoic-Mesozoic intracontinental orogenic process andintermedate-acidic igneous rocks from the Eastern Kunlun Mountains of northwestern China. Geoscience, 12(3): 344-352. (in Chinese with English abstract)
Huang H, Niu Y L, Nowell G, et al. 2014. Geochemical constraints on the petrogenesis of granitoids in the East Kunlun orogenic belt, northern Tibetan Plateau: implications for continental crust growth through syn-collisional felsic magmatism. Chemical Geology, 370: 1-18.
Jiang C F, Yang J S, Fen B G. 1992. Opening-closing tectonics of the Kunlun Mountain. Beijing: Geological Publishing House, 183-217. (in Chinese)
Jiang C F, Wang Z Q, Li M T. 2000. Opening-closing tectonics of the central orogenic belt. Beijing: Geological Publishing House,1-154. (in Chinese)
Li R B. 2012. Research on the Late Paleozoic--Early Mesozoic orogeny in East Kunlun orogen: doctor's degree thesis. Xi'an: Chang'an University. (in Chinese with English abstract)
Li R B, Pei X Z, Li Z C, et al. 2018. Paleo-Tethys Ocean subduction in eastern section of East Kunlun orogen: evidence from the geochronology and geochemistry of the Wutuo pluton. Acta Petrologica Sinica, 34(11): 3399-3421. (in Chinese with English abstract)
Liu H T. 2005. Petrology, geochemistry and geochronology of Late Triassic volcanics, Kunlun orogenic belt, western China: implications for tectonic setting and petrogenesis. Geochemical Journal, 39(1): 1-20.
Liu Y S, Hu Z C, Gao S, et al. 2008. In situ analysis of major and trace elements anhydrous minerals by LA-ICP-MS without applying an internal standards. Chemical Geology, 257(1/2): 34-43.
Liu Y S, Hu Z C, Gao S, et al. 2010. Continental and oceanic crust recycling-induced melt-periotite interactions in the Trans-North China orogen:U-Pb dating,Hf isotopes and trace elements in zircons from mantle xenoliths. Journal of Petrology, 51(1/2): 537-571.
Luo Z H, Deng J F, Cao Y Q, et al. 1999. On Late Paleozoic-Early Mesozoic volcanism and regional tectonic evolution of Eastern Kunlun, Qinghai Province. Geoscience, 13(1): 51-56. (in Chinese with English abstract)
Ludwig K R. 2003. User's manual for Isoplot 3.00: a geochronological toolkit for Microsoft Excel. Berkeley: Berkeley Geochronology Center Special Publication, 1-70.
Ma C Q,Xiong F H,Yin S,et al. 2015. Intensity and cyclicity of orogenic magmatism: an example from a Paleo-Tethyan granitoid batholith, eastern Kunlun, northern Qinghai--Tibetan Plateau. Acta Petrologica Sinica, 31(12): 3555-3568. (in Chinese with English abstract)
Mo X X, Luo Z H, Deng J F, et al. 2007. Granitoids and crustal growth and in the East-Kunlun orogenic belt. Geological Journal of China Universities, 13(3): 403-414. (in Chinese with English abstract).
Richards J P. 2003. Tectono-magmatic precursors for porphyry Cu-(Mo-Au) deposit formation. Economic Geology, 98(8):1515-1533.
Saunders A D, Norry M J, Tarney J. 1998. Origin of MORE and chemically depleted mantle reservoirs: trace element constraints. Journal of Petrology, Special Volume (1): 415-445.
Song B, Zhang Y H, Wan Y S, et al. 2002. Mount making and procedure of the SHRIMP dating. Geological Review, 48(Suppl.): 26-30. (in Chinese with English abstract)
Song Z B, Zhang Y L, Chen X Y, et al. 2013.Geochemical characteristics of Harizha granite diorite-porphyry in East Kunlun and their geological implications. Mineral Deposits, 32(1): 157-168. (in Chinese with English abstract)
Sun F Y, Li B L, Ding Q F. 2009. Report of major ore-prospecting problems study in East Kunlun metallogenic belt. Changchun: Institute of Geological Survey of Jilin University. (in Chinese)
Tang J, Ren J Q, Wang L, et al. 2008. Comprehensive investigation report of 1:50 000 regional mineral geology, sediment geochemistry and high precision magnetic survey in Chahan Wusu River area, Dulan County, Qinghai Province. Xining: Institute of Geological Survey of Qinghai Province. (in Chinese)
Taylor S R, McLennan S M. 1995. Layered igneous rocks. San Francisco: Freeman WH & CO, 150-203.
Vervoort J D, Patchett P J. 1996. Behavior of hafnium and neodymium isotopes in the crust: constraints from Precambrian crustally derived granites. Geochimica et Cosmochimica Acta, 60: 3717-3733.
Whalen J B, Carrie K L, Chappell B W. 1987. A-type granites: geochemical characteristics, discrimination and petrogenesis. Contribution to Mineralogy and Petrology, 95: 407-419.
Wolf M B, Wyllie P J. 1994. Dehydration-melting of amphibolite at 10 kbar: the effects of temperature and Time. Contributions to Mineralogy and Petrology, 115(4): 369-383.
Wu F Y, Yang Y H, Xie L W, et al. 2006. Hf isotopic compositions of the standard zircons and baddeleyites used in U-Pb geochronology. Chemical Geology, 234:105-126.
Wu F Y, Li X H, Zheng Y F, et al. 2007. Lu-Hf isotopic systematics and their applications in petrology. Acta Petrologica Sinica, 23(2):185-220. (in Chinese with English abstract)
Xiong X L, Adam J, Green T H. 2005. Rutile stability and rutile/melt HFSE partitioning during partial melting of hydrous basalt: implications for TTG genesis. Chemical Geology, 218: 339-359.
Xu Z Q, Yang J S, Li W C, et al. 2013. Paleo-Tethys system and accretionary orogen in the Tibet Plateau. Acta Petrologica Sinica, 29(6): 1847-1860. (in Chinese with English abstract)
Yang H L, Gao S, Liu X M, et al. 2004. Accurate U-Pb age and trace element determinations of zircon by laser ablation-inductively coupled plasma-mass spectrometry. Geostandards and Geoanalytical Research, 28(3): 353-370.
Yang J S, Robinson P T, Jiang C F, et al.1996. Ophiolites of the Kunlun Mountains, China and their tectonic implications. Tectonophysics, 258(1): 215-231.
Yang J S, Xu Z Q, Li H B, et al. 2005. The Paleo-Tethyan volcanism and plate tectonic regime in the A'nyemaqen region of East Kunlun, northern Tibet Plateau. Acta Petrologica et Mineralogica, 24(5): 369-380. (in Chinese with English abstract)
Yin H F, Zhang K X. 1998. Evolution and characteristics of the central orogenic belt. Earth Science, 23(5): 438-442.(in Chinese with English abstract)
Yuan C,Sun M,Xiao W J,et al. 2009. Garnet-bearing tonalitic porphyry from East Kunlun, northeast Tibetan Plateau: Implications for adakite and magmas from the mashzone. International Journal of Earth Sciences, 98(6): 1489-1510.
Zhang Q, Wang Y, Li C D, et al. 2006. Granitite classification on the basis of Sr and Yb contents and its implications. Acta Petrologica Sinica, 22(9): 2249-2269. (in Chinese with English abstract)