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大陆碰撞过程中地壳深熔的岩石学证据:以苏鲁造山带超高压变质岩为例

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Keywords: 大陆深俯冲,超高压变质作用,地壳深熔,元素活动,深熔锆石

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Abstract:

岩石学显微结构证据表明,苏鲁造山带西南部超高压变质岩石经历了不同程度的深熔作用.在花岗片麻岩和石英岩中识别出结晶自深熔熔体的锆石,其U-Pb年龄集中在220±2Ma.少量深熔锆石含有柯石英包裹体,U-Pb年龄主要集中在224±2Ma,部分与含较低压矿物包裹体的锆石域类似.因此,深熔作用开始于早期折返阶段,部分仍处于超高压变质域.折返过程中多硅白云母脱水熔融是这些岩石发生深熔的主要机制.黝帘石榴辉岩的石榴石和绿辉石中发现了由石英+斜长石±钾长石±重晶石组成的多相固体包裹体.它们具有高钠和变化的钾含量,可能是榴辉岩中黝帘石和多硅白云母脱水分解诱发部分熔融形成,同时深熔过程中有大量绿辉石的参与.超高压变质岩石在地幔深度的部分熔融,可能促进了深俯冲陆壳在俯冲隧道内部的快速折返.

References

[1]  1 Hermann J, Rubatto D, Korsakov A, et al. Multiple zircon growth during fast exhumation of diamondiferous, deeply subducted continental crust (Kokchetav Massif, Kazakhstan). Contrib Mineral Petrol, 2001, 141: 66-82
[2]  2 Wallis S, Tsuboi M, Suzuki K, et al. Role of partial melting in the evolution of the Sulu (eastern China) ultrahigh-pressure terrane. Geology, 2005, 33: 129-132
[3]  3 Liu F L, Robinson P T, Gerdes A, et al. Zircon U-Pb ages, REE concentrations and Hf isotope compositions of granitic leucosome and pegmatite from the north Sulu UHP terrane in China: Constraints on the timing and nature of partial melting. Lithos, 2010, 117: 247-268
[4]  4 Liu F L, Robinson P T, Liu P H. Multiple partial melting events in the Sulu UHP terrane: Zircon U-Pb dating of granitic leucosomes within amphibolite and gneiss. J Metamorph Geol, 2012, 30: 887-906
[5]  5 Zong K Q, Liu Y S, Hu Z C, et al. Melting-induced fluid flow during exhumation of gneisses of the Sulu ultrahigh-pressure terrane. Lithos,2010, 120: 490-510
[6]  6 Labrousse L, Prouteau G, Ganzhorn A C. Continental exhumation triggered by partial melting at ultrahigh pressure. Geology, 2011, 39:1171-1174
[7]  7 Zheng Y F, Xia Q X, Chen R X, et al. Partial melting, fluid supercriticality and element mobility in ultrahigh-pressure metamorphic rocks during continental collision. Earth-Sci Rev, 2011, 107: 342-374
[8]  8 Zheng Y F. Metamorphic chemical geodynamics in continental subduction zones. Chem Geol, 2012, 328: 5-48
[9]  9 Rosenberg C L, Handy M R. Experimental deformation of partially melted granite revisited: Implications for the continental crust. J Metamorph Geol, 2005, 23: 19-28
[10]  10 Chen Y X, Zheng Y F, Hu Z C. Synexhumation anatexis of ultrahigh-pressure metamorphic rocks: Petrological evidence from granitic gneiss in the Sulu orogen. Lithos, 2013, 156-159: 69-96
[11]  14 Zheng Y F, Fu B, Gong B, et al. Stable isotope geochemistry of ultrahigh pressure metamorphic rocks from the Dabie-Sulu orogen in China: Implications for geodynamics and fluid regime. Earth-Sci Rev, 2003, 62: 105-161
[12]  15 Zheng Y F, Chen R X, Zhao Z F. Chemical geodynamics of continental subduction-zone metamorphism: Insights from studies of the Chinese Continental Scientific Drilling (CCSD) core samples. Tectonophysics, 2009, 475: 327-358
[13]  16 曾令森, 梁凤华, Asimow P, 等. 深俯冲陆壳岩石部分熔融与苏鲁超高压榴辉岩中长英质多晶包裹体的形成. 科学通报, 2009, 54:1826-1840
[14]  24 Vielzeuf D, Holloway J R. Experimental determination of the fluid-absent melting relations in the pelitic system. Contrib Mineral Petrol,1988, 98: 257-276
[15]  27 Skjerlie K P, Patino Douce A E. The fluid-absent partial melting of a zoisite-bearing quartz eclogite from 1.0 to 3.2 GPa; Implications for melting in thickened continental crust and for subduction-zone processes. J Petrol, 2002, 43: 291-314
[16]  11 Chen Y X, Zheng Y F, Hu Z C. Petrological and zircon evidence for anatexis of UHP quartzite during continental collision in the Sulu orogen. J Metamorph Geol, 2013, 31: 389-413
[17]  12 Holness M B, Cesare B, Sawyer E W. Melted rocks under the microscope: Microstructures and their interpretation. Elements, 2011, 7:247-252
[18]  13 Holness M B, Sawyer E W. On the pseudomorphing of melt-filled pores during the crystallization of migmatites. J Petrol, 2008, 49:1343-1363
[19]  17 Gao X Y, Zheng Y F, Chen Y X. Dehydration melting of ultrahigh-pressure eclogite in the Dabie orogen: Evidence from multiphase solid inclusions in garnet. J Metamorph Geol, 2012, 30: 193-212
[20]  18 Gao X Y, Zheng Y F, Chen Y X, et al. Trace element composition of continentally subducted slab-derived melt: Insight from multiphase solid inclusions in ultrahigh-pressure eclogite in the Dabie orogen. J Metamorph Geol, 2013, 31: 453-468
[21]  19 Hermann J, Rubatto D. Accessory phase control on the trace element signature of sediment melts in subduction zones. Chem Geol, 2009,265: 512-526
[22]  20 Gregory C J, Rubatto D, Hermann J, et al. Allanite behaviour during incipient melting in the southern Central Alps. Geochim Cosmochim Acta, 2012, 84: 433-458
[23]  21 Taylor H P, Sheppard S M F. Igneous rocks; I, Processes of isotopic fractionation and isotope systematics. Rev Mineral Geochem, 1986,16: 227-271
[24]  22 Valley J W. Oxygen isotopes in zircon. Rev Mineral Geochem, 2003, 53: 343-385
[25]  23 Zhao Z F, Zheng Y F. Calculation of oxygen isotope fractionation in magmatic rocks. Chem Geol, 2003, 193: 59-80
[26]  25 Hermann J. Experimental constraints on phase relations in subducted continental crust. Contrib Mineral Petrol, 2002, 143: 219-235
[27]  26 刘强, 金振民, 章军锋. 1.5~3.0 GPa 压力条件下多硅白云母榴辉岩的脱水熔融实验研究. 科学通报, 2009, 54: 1455-1464

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