Citation: | ZHANG Shizhen, LI Fenqi, LIU Han, LI Jun, GOU Zhengbin, QIN Yadong. The Early Cretaceous gabbro in Yare area, middle Lhasa Block: Magmatism response to the slab break-off of the southward subduction Bangong-Nujiang Ocean lithosphere[J]. Geological Bulletin of China, 2021, 40(11): 1852-1864. |
In order to understand the Early Cretaceous tectonic-magmatic process in the central and north Lhasa Block, the Early Cretaceous gabbro in the Yare area of western part of middle Lhasa Block were studied.The zircon U-Pb age of gabbro is 115.5±0.5 Ma.The rocks belong to tholeiite series, and their characteristics of rare earth elements are similar to those of oceanic island basalt (OIB).Mg# value (46.07~48.05) and contents of Cr (6.97×10-6~18.5×10-6), Ni (6.87×10-6~11.2×10-6) are relatively low.The large ion lithophile elements such as Rb, Ba, K, Sr of gabbro samples are relatively enriched, Th、U and Pb show positive anomalies, and the high field strength elements such as Nb, Ta, Zr, Hf, P and Ti show negative anomalies, indicating that the gabbro samples have some "arc volcanic rock" properties.The gabbro show positive zircon εHf (t) values (+4.3~+7.9) and younger Hf-depleted mantle model ages (TDM1) of 489~614 Ma.By comprehensive analysis, it is proposed that the Early Cretaceous gabbro in the Yare area is most likely triggered by the slab break-off of the southward subducting Bangong-Nujiang Tethyan Ocean lithosphere, and can be considered as the product of partial melting of the asthenosphere mantle which was metasomatized by recent melts or supercritical fluids from the subduction slab, and subsequently experienced varying degrees of fractional crystallization.
[1] | Coulon C, Maluski H, Bollinger C, et al. Mesozoic and Cenozoic volcanic rocks from central and southern Tibet: 39Ar/40Ar dating, petrological characteristics and geodynamical significance[J]. Earth and Planetary Science Letters, 1986, 79(3/4): 281-302. |
[2] | Ding L, Kapp P, Zhong D L, et al. Cenozoic volcanismin Tibet: evidence for a transition from oceanic to continental subduction[J]. Journal of Petrology, 2003, 44(10): 1833-1865. doi: 10.1093/petrology/egg061 |
[3] | Kapp P, DeCelles P G, Gehrels G E, et al. Geological records of the Lhasa-Qiangtang and Indo-Asian collisions in the Nima area of central Tibet[J]. Geological Society of America Bulletin, 2007, 119(7/8): 917-932. |
[4] | 马国林, 岳雅慧. 西藏拉萨地块北部白垩纪火山岩及其对冈底斯岛弧构造演化的制约[J]. 岩石矿物学杂志, 2010, 29(5): 525-538. doi: 10.3969/j.issn.1000-6524.2010.05.008 |
[5] | 崔浩杰, 苟正彬, 刘函, 等. 拉萨地块西段尼雄地区早白垩世晚期花岗闪长岩的成因及构造意义[J]. 沉积与特提斯地质, 2019, 39(1): 1-13. doi: 10.3969/j.issn.1009-3850.2019.01.001 |
[6] | 康志强, 许继峰, 董彦辉, 等. 拉萨地块中北部白垩纪则弄群火山岩: Slainajap洋南向俯冲的产物[J]. 岩石学报, 2008, 24(2): 303-314. |
[7] | 张彤, 黄波, 罗改, 等. 西藏中冈底斯带北部早白垩世构造属性: 来自则弄群火山岩锆石U-Pb年龄及地球化学的制约[J]. 沉积与特提斯地质, 2020, 40(2): 75-90. |
[8] | 朱弟成, 莫宣学, 赵志丹, 等. 西藏冈底斯带措勤地区则弄群火山岩锆石U-Pb年代学格架及构造意义[J]. 岩石学报, 2008, 24(3): 401-412. |
[9] | 康志强, 许继峰, 王保弟, 等. 拉萨地块北部白垩纪多尼组火山岩的地球化学: 形成的构造环境[J]. 地球科学, 2009, 34(1): 89-104. |
[10] | 高顺宝, 郑有业, 王进寿, 等. 西藏班戈地区侵入岩年代学和地球化学: 对班公湖-怒江洋盆演化时限的制约[J]. 岩石学报, 2011, 27(7): 1973-1982. |
[11] | 黄瀚霄, 李光明, 董随亮, 等. 西藏班戈地区青龙花岗闪长岩SHRIMP锆石U-Pb年龄及其地球化学特征[J]. 地质通报, 2012, 31(6): 852-859. doi: 10.3969/j.issn.1671-2552.2012.06.004 |
[12] | Qu X M, Wang R J, Xin H B, et al. Age and petrogenesis of A-type granites in the middle segment ofthe Bangonghu-Nujiang suture, Tibetan plateau[J]. Lithos, 2012, 146/147: 264-275. doi: 10.1016/j.lithos.2012.05.006 |
[13] | 张予杰, 刘伟, 朱同兴, 等. 西藏申扎县买巴地区早白垩世侵入岩锆石U-Pb年龄及地球化学[J]. 中国地质, 2014, 41(1): 50-60. doi: 10.3969/j.issn.1000-3657.2014.01.004 |
[14] | 隋清霖. 西藏拉萨地块盐湖地区早白垩世岩浆岩年代学、岩石成因及构造意义[D]. 中国地质大学(北京) 硕士学位论文, 2014. |
[15] | Wu H, Li C, Xu M J, et al. Early Cretaceous adakitic magmatism in the Dachagou area, northern Lhasa terrane, Tibet: Implications for slab roll-back and subsequent slab breakoff of the lithosphere of the Bangong-Nujiang Ocean[J]. Journal of Asian Earth Sciences, 2015, 97: 51-66. doi: 10.1016/j.jseaes.2014.10.014 |
[16] | 齐宁远, 赵志丹, 唐演, 等. 西藏中拉萨地块西段左左乡晚侏罗世-早白垩世花岗岩年代学、地球化学与岩石成因[J]. 岩石学报, 2019, 35(2): 405-422. |
[17] | 尹滔, 李威, 尹显科, 等. 西藏阿翁错地区早白垩世花岗闪长岩——班公湖-怒江洋壳南向俯冲消减证据[J]. 中国地质, 2019, 46(5): 1105-1115. |
[18] | Zhu D C, Mo X X, Niu Y L, et al. Geochemical investigation of Early Cretaceous igneous rocks along an east-west traverse throughout the central Lhasa Terrane, Tibet[J]. Chemical Geology, 2009, 268(3/4): 298-312. |
[19] | Zhu D C, Zhao Z D, Niu Y L, et al. The Lhasa Terrane: Record of a microcontinent and its histories of drift and growth[J]. Earth and Planetary Science Letters, 2011, 301(1/2): 241-255. |
[20] | 张亮亮, 朱弟成, 赵志丹, 等. 西藏北冈底斯巴尔达地区岩浆作用的成因: 地球化学、年代学及Sr-Nd-Hf同位素约束[J]. 岩石学报, 2010, 26(6): 1871-1886. |
[21] | 张亮亮, 朱弟成, 赵志丹, 等. 西藏申扎早白垩世花岗岩类: 板片断离的证据[J]. 岩石学报, 2011, 27(7): 1938-1946. |
[22] | 张晓倩, 朱弟成, 赵志丹, 等. 西藏措勤麦嘎岩基的锆石U-Pb年代学、地球化学和锆石Hf同位素: 对中部拉萨地块早白垩世花岗岩类岩石成因的约束[J]. 岩石学报, 2012, 28(5): 1615-1634. |
[23] | Chen Y, Zhu D C, Zhao Z D, et al. Slab breakoff triggered Ca. 113Ma mamgatism around Xainza area of the Lhasa Terrane, Tibet[J]. Gondwana Research, 2014, 26(2): 449-463. doi: 10.1016/j.gr.2013.06.005 |
[24] | Sui Q L, Wang Q, Zhu D C, et al. Compositional diversity of ca. 110 Ma magmatism in the northern Lhasa Terrane, Tibet: Implications for the magmatic origin and crustal growth in a continent-continent collision zone[J]. Lithos, 2013, 168/169: 145-159. |
[25] | 潘桂棠, 莫宣学, 侯增谦, 等. 冈底斯造山带的时空结构及演化[J]. 岩石学报, 2006, 22(3): 521-533. |
[26] | Liu Y S, Hu Z C, Zong K Q, et al. Reappraisement and refinement of zircon U-Pb isotope and trace element analyses by LA-ICP-MS[J]. Chinese Science Bulletin, 2010, 55(15): 1535-1546. doi: 10.1007/s11434-010-3052-4 |
[27] | Hu Z C, Zhang W, Liu Y S, et al. "Wave" signal-smoothing and mercury-removing device for laser ablation quadrupole and multiple collector ICPMS analysis: Application to lead isotope analysis[J]. Analytical Chemistry, 2015, 87(2): 1152-1157. doi: 10.1021/ac503749k |
[28] | 吴福元, 李献华, 郑永飞, 等. Lu-Hf同位素体系及其岩石学应用[J]. 岩石学报, 2007, 23(2): 185-220. |
[29] | Wu Y B, Zheng Y F. Genesis of Zircon and Itsconstraints On Interpretation of U-Pb Age[J]. Chinese Science Bulletin, 2004, 49(15): 1554-1569. doi: 10.1007/BF03184122 |
[30] | Sun S S, Mcdonough W F. Chemical and isotopic systematics of Oceanic Basalts: Implications for mantle composition and processes[C]//Saunders A D, Norry M J. Magmatism in the Ocean Basins. London: Geological Society, London, Special Publications, 1989, 42(1): 313-345. |
[31] | 杨婧, 王金荣, 张族, 等. 全球多弧玄武岩数据挖据——在玄武岩判别图解上的表现及初步解释[J]. 地质通报, 2016, 35(12) 1937-1949. doi: 10.3969/j.issn.1671-2552.2016.12.001 |
[32] | Ormerod D S, Hawkesworth C J, Rogers N W, et al. Tectonic and magmatic transitions in the western Great Basin, USA[J]. Nature, 1988, 333(6171): 349-353. doi: 10.1038/333349a0 |
[33] | Zhou Z H, Mao J W, Peter L. Geochronology and isotopic geochemistry of the A-type granites from the Huanggang Sn-Fe deposit, southern Great Hinggan Range, NE China: Implication for their origin and tectonic setting[J]. Journal of Asian Earth Sciences, 2012, 49: 272-286. doi: 10.1016/j.jseaes.2012.01.015 |
[34] | 彭树华, 孙立新, 时学忠, 等. 冀北三面井岩体时代、地球化学特征及其地质意义[J]. 世界地质, 2013, 32(4): 694-706 doi: 10.3969/j.issn.1004-5589.2013.04.006 |
[35] | 杨岳衡, 张宏福, 谢烈文, 等. 华北克拉通中、新生代典型火山岩的岩石成因: Hf同位素新证据[J]. 岩石学报, 2006, 22(6): 1665-1671. |
[36] | Shi Y R, Liu D Y, Miao L C, et al. Devonian A-type granitic magmatism on the northern margin of the North China Craton: SHRIMP U-Pb zircon dating and Hf-isotopes of the Hongshan granite at Chifeng, Inner Mongolia, China[J]. Gondwana Research, 2010, 17(4): 632-641. doi: 10.1016/j.gr.2009.11.011 |
[37] | 第五春荣, 孙勇, 王倩. 华北克拉通地壳生长和演化: 来自现代河流碎屑锆石Hf同位素组成的启示[J]. 岩石学报, 2012, 28(11): 3520-3530. |
[38] | 杨浩田, 杨德彬, 师江朋, 等. 鲁西早白垩世岩石圈地幔的属性: 大昆仑辉长岩和辉绿岩年代学、岩石地球化学和Sr-Nd-Pb-Hf同位素制约[J]. 岩石学报, 2018, 34(11): 3327-3340 |
[39] | 岳维好, 周家喜. 青海都兰县阿斯哈石英闪长岩岩石地球化学、锆石U-Pb年龄与Hf同位素特征[J]. 地质通报, 2019, 38(2/3): 328-338. |
[40] | 许强伟, 王玭, 王志强, 等. 内蒙古克什克腾旗长岭子斜长花岗斑岩锆石U-Pb年龄、成因与碰撞造山作用[J]. 中国地质, 2021, 48(1): 229-246. |
[41] | 梁国科, 吴祥珂, 蔡逸涛, 等. 桂北罗城地区云煌岩成因——地球化学及U-Pb年龄约束[J]. 地质通报, 2020, 39(2/3): 267-278. |
[42] | Neal C R, Mahoney J J, Chazey W J. Mantle sources and the highly variable role of continental lithosphere in basalt petrogenisis of the Kerguelen Plateau and Broken Ridge LIP: Results from ODP leg 183[J]. Journal of Petrology, 2002, 43(7): 1177-1205 doi: 10.1093/petrology/43.7.1177 |
[43] | 朱弟成, 潘桂棠, 莫宣学, 等. 青藏高原中部中生代OIB型玄武岩的识别: 年代学、地球化学及其构造环境[J]. 地质学报, 2006, 80(9): 1312-1328. doi: 10.3321/j.issn:0001-5717.2006.09.008 |
[44] | Rudnick R L, Gao S. Composition of the continental crust[C]//Holland H D, Turekian K K. Treatise on Geochemistry(Second Edition). Oxford: Elsevier, 2014, 4: 1-51. |
[45] | Zhao J H, Zhou M F. Geochemistry of Neoproterozoic mafic intrusions in the Panzhihua district(Sichuan Province, SW China): implications for subduction-related metasomatism in the upper mantle[J]. Precambrian Research, 2007, 152(1): 27-47. |
[46] | 杨崇辉, 杜利林, 任留东, 等. 中条山铜矿峪变质火山岩的时代、构造背景及对成矿的制约[J]. 地球学报, 2015, 36(5): 613-633. |
[47] | Kessel R, Schmidt M W, Ulmer P, et al. Trace element signature of subduction-zone fluids, melts and supercritical liquids at 120-180 km depth[J]. Nature, 2005, 437(29): 724-727. |
[48] | Pearce J A. Trace element characteristics of lave from destructive plate boundaries[C]//Thorpe R S. Orogenic andesites and related rocks. Chichester: John Wiley and Sons, 1982: 528-548. |
[49] | 杨逸云, 赵志丹, 雷杭山, 等. 云南腾冲全新世火山岩岩浆演化和岩石成因[J]. 岩石学报, 2019, 35(2): 472-484. |
[50] | Yu Y, Huang X L, Sun M, et al. Missing Sr-Nd isotopic decoupling in subduction zone: Decoding the multi-stage dehydration and melting of subducted slab in the Chinese Altai[J]. Lithos, 2020, 362/363, 105465: 1-14. |
[51] | Woodhead J D, Hergt J M, Davidson J P, et al. Hafnium isotope evidence for conservative element mobility during subduction zone process[J]. Earth and Planetary Science Letters, 2001, 192(3): 331-346. doi: 10.1016/S0012-821X(01)00453-8 |
[52] | Kohut E J, Stern R J, Kent A R L, et al. Evidence for adiabatic decompression melting in the Southern Mariana Arc from high-Mg lavas and melt inclusions[J]. Contributions to Mineralogy and Petrology, 2006, 152(2): 201-221. doi: 10.1007/s00410-006-0102-7 |
[53] | Li W C, Ni H W. Dehydration at subduction zones and the geochemistry of slab fluids[J]. Science China Earth Sciences, 2020, 63(12): 1925-1937. doi: 10.1007/s11430-019-9655-1 |
[54] | Xiong X L, Liu X C, Li L, et al. The partitioning behavior of trace elements in subduction zones: Advances and prospects[J]. Science China Earth Sciences, 2020, 63(12): 1938-1951. doi: 10.1007/s11430-019-9631-6 |
[55] | 邱检生, 胡建, 蒋少涌, 等. 鲁西中、新生代镁铁质岩浆作用与地幔化学演化[J]. 地球科学——中国地质大学学报, 2005, 30(6): 646-658. |
[56] | 徐向珍, 熊发挥, 杨经绥, 等. 冈底斯中段卡热辉长岩锆石U-Pb年代学、地球化学及构造意义[J]. 地质学报, 2019, 93(10): 2542-2555. doi: 10.3969/j.issn.0001-5717.2019.10.011 |
[57] | Frey F A, Green D H, Roy S D. Integrated models of basalt petrogenesis: A study of quartz tholeiites to olivine melilitites from southeastern Australia utilizing geochemical and experimental petrological data[J]. Journal of Petrology, 1978, 19(3): 463-513. doi: 10.1093/petrology/19.3.463 |
[58] | Hess P C. Phase equilibria constraints on the origin of ocean floor basalts[C]//Morgan J P, Blackman D K, Sinton J M. Mantle Flow and Melt Generation at Mid-Ocean Ridges. 1992, 71: 67-102. |
[59] | 李永军, 沈锐, 王冉, 等. 新疆西准噶尔巴尔努克早石炭世富Nb岛弧玄武岩的发现及其地质意义[J]. 岩石学报, 2014, 30(12): 3501-3511. |
[60] | 夏林圻, 夏祖春, 徐学义, 等. 利用地球化学方法判别大陆玄武岩和岛弧玄武岩[J]. 岩石矿物学杂志, 2007, 26(1): 77-89. doi: 10.3969/j.issn.1000-6524.2007.01.011 |
[61] | Pearce J A. Role of the sub-continental lithosphere in magma genesis at active continental margins[C]//Hawkesworth C J, Norry M J. Continental basalts and mantle xenoliths. Nantwich, Cheshire: Shiva Publications, 1983: 230-249. |
[62] | Pearce J A. Statistical analysis of major element patterns in basalts[J]. Journal of Petrology, 1976, 17(1): 15-43. doi: 10.1093/petrology/17.1.15 |
[63] | Meschede M. A method of discriminating between different types of mid-ocean ridge basalts and continental tholeiites with the Nb-Zr-Y diagram[J]. Chemical Geology, 1986, 56(3/4): 207-218. |
[64] | 汪云亮, 张成江, 修淑芝. 玄武岩类形成的大地构造环境的Th/Hf-Ta/Hf图解判别[J]. 岩石学报, 2001, 17(3): 413-421. |
[65] | Zhu D C, Zhao Z D, Niu Y L, et al. The origin and pre-Cenozoic evolution of the Tibetan Plateau[J]. Gondwana Research, 2012, 23(4): 1429-1454. |
[66] | Zhu D C, Li S M, Cawood P A, et al. Assembly of the Lhasa and Qiangtang Terranes in Central Tibet by divergent double subduction[J]. Lithos, 2016, 245: 7-17. doi: 10.1016/j.lithos.2015.06.023 |
[67] | Ferrari L. Slab detachment control on mafic volcanic pulse and mantle heterogeneity in Central Mexico[J]. Geology, 2004, 32(1): 77-80. doi: 10.1130/G19887.1 |
[68] | Duretz T, Gerya T V, May D A. Numerical modelling of spontaneous slab breakoff and subsequent topographic response[J]. Tectonophysics, 2011, 502(1/2): 244-256. |
[69] | 于枫. 西藏冈底斯盐湖南部花岗岩的岩石学、地球化学与成因[D]. 中国地质大学(北京) 硕士学位论文, 2010: 1-68. |
[70] | 于玉帅, 高原, 杨竹森, 等. 西藏措勤尼雄矿田滚纠铁矿侵入岩LA-ICP-MS锆石U-Pb年龄与地球化学特征[J]. 岩石学报, 2011, 27(7): 1949-1960. |
[71] | 曲晓明, 辛洪波, 杜德道, 等. 西藏班公湖-怒江缝合带中段碰撞后A型花岗岩的时代及其对洋盆时间的约束[J]. 地球化学, 2012, 41(1): 1-14. |
[72] | 苟正彬, 刘函, 李俊, 等. 拉萨地块中北部尼雄地区早白垩世火山岩的成因及构造意义[J]. 地球科学, 2018, 43(8): 2780-2794. |
Simplified tectonic map of the Lhasa Block (a) and simplified geological map of the study area (b)
Field photos (a, b) and photomicrographs (c, d) of the Early Cretaceous gabbro in the Yare area
CL images of the zircons from the Early Cretaceous gabbro in the Yare area
U-Pb concordia diagram (a) and weighted average age (b) of the zircons from the Early Cretaceous gabbro in the Yare area
TAS (a) and SiO2-TFeO/MgO (b) diagrams of the gabbro samples
The chondrite-normalized REE pattern (a) and primitive mantle-normalized trace element spider diagram (b) of the gabbro samples
Ba/La-Th/Yb (a) and Th/Nb-U/Th (b) diagrams of the gabbro samples
Zr-Zr/Y (a), F1-F2 (b), Zr/4-Nb×2-Y (c) and Ta/Hf-Th/Hf (d) diagrams of the gabbro samples