Characteristics and Tectonic Implications of Lithospheric Density Structures beneath Western Junggar and Its Surroundings
-
摘要: 对西准噶尔及周边地区壳幔结构的研究是揭示准噶尔盆地演化的重要基础.利用最新的卫星重力场模型, 通过计算得到西准噶尔及周边地区的布格重力异常, 进而采用三维反演技术, 对西准噶尔及周边地区的地壳与上地幔顶部进行密度成像, 得到了0~80 km深度范围的密度异常结构.地壳密度分布显示古准噶尔洋壳有可能向NE和NW分别俯冲于西伯利亚板块和西准噶尔地块之下.上地幔顶部密度变化表明: 阿尔泰褶皱带具有相对较低的密度, 可能为古大陆巨厚的硅铝层所致; 哈萨克斯坦-准噶尔盆地具有相对完整的高密度结构; 天山褶皱带区域的密度大幅度变化刻画了超岩石圈断裂对岩石圈的切割以及岩石圈形变与构造活动的痕迹.Abstract: Structures in the crust and uppermost mantle beneath western Junggar and its surroundings, the key to better understanding of the tectonic evolution of the Junggar basin, are studied in this paper. Firstly, the Bouguer gravity anomaly is calculated from the satellite gravitational field model. Then 3D inversion technique is utilized, and the density imaging is operated in the crust and uppermost mantle beneath the western Junggar and its surroundings and finally the anomalous density structure at the depth range of 0-80 km is obtained. Crustal density distribution in the ancient oceanic crust of the Junggar indicates the possible subductions under the Siberian plate northeastwardly and the western Junggar northwestwardly. Density distribution in the uppermost mantle suggests that the relatively low density beneath Altay fold belt may have resulted from the thick sialic layer of the ancient continent, and Kazakhstan plate & Junggar basin are dominated by a relatively whole high-density structure while the significant density changes beneath the Tianshan fold belt describe the ultra-crustal deep faults and also the nicks of the tectonic activities and the lithospheric deformations.
-
图 1 西准噶尔及邻区的区域大地构造示意
Ⅰ.西伯利亚板块：ⅠA.阿尔泰陆壳板段；ⅠB.准噶尔晚古生代早期活动大陆边缘板块；ⅠC.北准噶尔晚古生代早期洋壳板段；Ⅱ.哈萨克斯坦板块：ⅡA.北天山古生代活动大陆边缘段；ⅡB.伊犁-中天山陆壳板段；ⅡC.南天山早-中古生代活动大陆边缘板段；Ⅲ.塔里木板块：ⅢA.塔里木北缘陆壳板段、晚古生代末期-中新生代上叠构造盆地；JGB.准噶尔盆地；THB.吐鲁番-哈密盆地；TMB.塔里木盆地.根据肖序常等(1992)修绘
Fig. 1. The sketch of regional tectonics in the western Junggar and surroundings
图 2 研究区卫星重力异常
叠加底图为地形影像；a.布格重力异常；b.区域重力异常；c.局部重力异常
Fig. 2. Satellite gravity anomaly maps in the study region
图 3 不同深度的岩石圈密度异常水平切片(图例同图 2)
a.5 km；b.25 km；c.45 km；d.65 km
Fig. 3. Horizontal slices of lithospheric anomalous density distribution at different depths
-
Ai, K.K., Ji, L.J., 2015. Tectonic Rplift of Mountains in Northwestern Junggar since Late Cenozoic: Evidences from Sedimentology and Magnetic Fabric in Heshituoluogai Basin. Earth Science—Journal of China University of Geosciences, 40(3): 535-547 (in Chinese with English abstract). doi: 10.3799/dqkx.2015.042 Bai, W.J., Yang, J.S., 1985. On Continental Basin-Mountain Tectonic Framework and Continental Basin Spreading. Journal of Changchun College of Geology, (4): 21-28 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-CCDZ198504003.htm Chen, B., Arakawa, Y., 2005. Elemental and Nd-Sr Isotopic Geochemistry of Granitoids from the West Junggar Foldbelt (NW China), with Implications for Phanerozoic Continental Growth. Geochimica et Cosmochimica Acta, 69(5): 1307-1320. doi: 10.1016/j.gca.2004.09.019 Chen, B., Chen, C., Kaban, M.K., et al., 2013. Variations of the Effective Elastic Thickness over China and Surroundings and Their Relation to the Lithosphere Dynamics. Earth and Planetary Science Letters, 363: 61-72. doi: 10.1016/j.epsl.2012.12.022 Chen, B., Jahn, B.M., 2004. Genesis of Post-Collisional Granitoids and Basement Nature of the Junggar Terrane, NW China: Nd-Sr Isotope and Trace Element Evidence. Journal of Asian Earth Sciences, 23(5): 691-703. doi: 10.1016/s1367-9120(03)00118-4 Chen, J.F., Han, B.F., Zhang, L., 2010. Geochemistry, Sr-Nd Isotopes and Tectonic Implications of Two Generations of Late Paleozoic Plutons in Northern Wes Junggar, Northwest China. Acta Petrologica Sinica, 26(8): 2317-2335 (in Chinese with English abstract). http://www.oalib.com/paper/1474907 Chen, S., Guo, Z.J., 2010. Time Constraints, Tectonic Setting of Dalabute Ophiolitic Complex and Its Significance for Late Paleozoic Tectonic Evolution in West Junggar. Acta Petrologica Sinica, 26(8): 2336-2344 (in Chinese with English abstract). http://www.researchgate.net/publication/281549166_Time_constraints_tectonic_setting_of_Dalabute_ophiolitic_complex_and_its_significance_for_Late_Paleozoic_tectonic_evolution_in_West_Junggar Cheng, S.D., Wang, G.R., Yang, S.D., et al., 1986. The Paleoplate Tectonic of Xinjiang. Xinjiang Geology, 4(2): 1-26 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-XJDI198602000.htm Cheng, Y.Q., Shen, Y.H., Zhang, L.C., et al., 1995. Tectonic Constitution and Evolution of the Chinese Continent. Regional Geology of China, (4): 289-294 (in Chinese with English abstract). http://www.cnki.com.cn/Article/CJFDTotal-ZQYD504.000.htm Coleman, R.G., 1989. Continental Growth of Northwest China. Tectonics, 8(3): 621-635. doi: 10.1029/tc008i003p00621 Du, J.S., 2014. Study on Processing, forward Modeling and Inversion Algorithms of Satellite Magnetic Anomaly Data in Spherical Coordinate System (Dissertation). China University of Geosciences, Wuhan (in Chinese with English abstract). Fang, J., 2006. Isostatic Gravity Anomaly and Its Geodynamic Characters in China and Its Adjacent Regions. Postdoctoral Research Report, Institute of Geology, China Earthquake Administration, Beijing (in Chinese with English abstract). Feng, Y., Coleman, R.G., Tilton, G., et al., 1989. Tectonic Evolution of the West Junggar Region, Xinjiang, China. Tectonics, 8(4): 729-752. doi: 10.1029/tc008i004p00729 Feng, Y.M., 1986. Types of Ophiolites in West Junggar. Bull. Xi'an Inst. Geol. Min. Res., Chinese Acad. Geol. Sci., (13): 37-45 (in Chinese with English abstract). Gao, R., Xiao, L., Wang, G.C., et al., 2013. Paleozoic Magmatism and Tectonic Setting in West Junggar. Acta Petrologica Sinica, 29(10): 3413-3434 (in Chinese with English abstract). http://www.researchgate.net/publication/285747232_Paleozoic_Magmatism_and_Tectonic_Setting_in_West_Junggar Geng, H.Y., Sun, M., Yuan, C., et al., 2009. Geochemical, Sr-Nd and Zircon U-Pb-Hf Isotopic Studies of Late Carboniferous Magmatism in the West Junggar, Xinjiang: Implications for Ridge Subduction?Chemical Geology, 266(3-4): 364-389. doi: 10.1016/j.chemgeo.2009.07.001 Guo, B., Liu, Q.Y., Chen, J.H., et al., 2006. Seismic Tomography of the Crust and Upper Mantle Structure Underneath the Chinese Tianshan. Chinese J. Geophys., 49(6): 1693-1700 (in Chinese with English abstract). doi: 10.1002/cjg2.997 Han, B.F., Ji, J.Q., Song, B., et al., 2006. Late Paleozoic Vertical Growth of Continental Crust around the Junggar Basin, Xinjiang, China (Part I): Timing of Post-Collisional Plutonism. Acta Petrologica Sinica, 22(5): 1077-1086 (in Chinese with English abstract). He, G.Q., Li, M.S., Liu, D.Q., 1994. Paleozoic Crustal Evolution and Mineralization in Xinjiang of China. Xinjiang People's Publishing House, Urumqi (in Chinese with English abstract). He, G.Q., Liu, J.B., Zhang, Y.Q., et al., 2007. Keramay Ophiolitic Mélange Formed during Earth Paleozoic in Western Junggar Basin. Acta Petrologica Sinica, 23(7): 1573-1576 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-YSXB200707001.htm Hu, A.Q., Jahn, B.M., Zhang, G.X., et al., 2000. Crustal Evolution and Phanerozoic Crustal Growth in Northern Xinjiang: Nd Isotopic Evidence. Part I. Isotopic Characterization of Basement Rocks. Tectonophysics, 328(1-2): 15-51. doi: 10.1016/s0040-1951(00)00176-1 Kwon, S.T., Tilton, G.R., Coleman, R.G., et al., 1989. Isotopic Studies Bearing on the Tectonics of the West Junggar Region, Xinjiang, China. Tectonics, 8(4): 719-727. doi: 10.1029/tc008i004p00719 Li, J.Y., Xiao, X.C., Tang, Y.Q., et al., 1990. Main Characteristics of Late Paleozoic Plate Tectonics in the Southern Part of East Junggar, Xinjiang. Geological Review, 36(4): 305-316 (in Chinese with English abstract). http://www.researchgate.net/publication/313240678_The_main_characteristics_of_Late_Paleozoic_plate_tectonics_in_the_southern_part_of_East_Junggar_Xinjiang Li, J.Y., Xiao, X.C., Tang, Y.Q., et al., 1992. Metal Deposits and Plate Tectonics in Northern Xinjiang. Xinjiang Geology, 10(2): 138-146 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-XJDI199202005.htm Li, Y.G., Oldenburg, D.W., 1998.3-D Inversion of Gravity Data. Geophysics, 63(1): 109-119. doi: 10.1190/1.1444302 Liu, X.J., Xu, J.F., Hou, Q.Y., et al., 2007. Geochemical Characteristic of Karamaili Ophiplite in East Junggar, Xinjiang: Products of Ridge Subduction. Acta Petrologica Sinica, 23(7): 1591-1602 (in Chinese with English abstract). http://www.researchgate.net/publication/279891839_Geochemical_characteristics_of_Karamaili_ophiolite_in_east_Junggar_Xingjiang_Products_of_ridge_subduction Ma, C., Xiao, W.J., Windley, B.F., et al., 2012. Tracing a Subducted Ridge-Transform System in a Late Carboniferous Accretionary Prism of the Southern Altaids: Orthogonal Sanukitoid Dyke Swarms in Western Junggar, NW China. Lithos, 140-141: 152-165. doi: 10.1016/j.lithos.2012.02.005 Qiu, R.Z., Li, W.Y., Zhou, S., et al., 2008. Lithospheric Types, Petrological Structures and Their Implications in Northwestern China Continent. Northwestern Geology, 41(2): 1-21 (in Chinese with English abstract). http://d.wanfangdata.com.cn/periodical/xbdz200802001 Şengör, A.M.C., Natalin, B.A., Burtman, V.S., 1993. Evolution of the Altaid Tectonic Collage and Palaeozoic Crustal Growth in Eurasia. Nature, 364(6435): 299-307. doi: 10.1038/364299a0 Shako, R., Fste, C., Abrykosov, O., et al., 2014. EIGEN-6C: A High-Resolution Global Gravity Combination Model Including GOCE Data. In: Flechtner, F., Sneeuw, N., Schuh, W.D., eds., Observation of the System Earth from Space-CHAMP, GRACE, GOCE and Future Missions. Springer, Berlin, 155-161. Tang, G.J., Wang, Q., Wyman, D.A., et al., 2010. Ridge Subduction and Crustal Growth in the Central Asian Orogenic Belt: Evidence from Late Carboniferous Adakites and High-Mg Diorites in the Western Junggar Region, Northern Xinjiang (West China). Chemical Geology, 277(3-4): 281-300. doi: 10.1016/j.chemgeo.2010.08.012 Tang, G.J., Wang, Q., Wyman, D.A., et al., 2012a. Recycling Oceanic Crust for Continental Crustal Growth: Sr-Nd-Hf Isotope Evidence from Granitoids in the Western Junggar Region, NW China. Lithos, 128-131: 73-83. doi: 10.1016/j.lithos.2011.11.003 Tang, G.J., Wang, Q., Wyman, D.A., et al., 2012b. Late Carboniferous High εNd(t)-εHf(t) Granitoids, Enclaves and Dikes in Western Junggar, NW China: Ridge-Subduction-Related Magmatism and Crustal Growth. Lithos, 140-141: 86-102. doi: 10.1016/j.lithos.2012.01.025 Tong, Y., Wang, T., Hong, D.W., et al., 2010. Spatial and Temporal Distribution of the Carboniferous-Permian Granitoids in Northern Xinjiang and Its Adjacent Areas, and Its Tectonic Significance. Acta Petrologica et Mineralogica, 29(6): 619-641 (in Chinese with English abstract). http://www.cqvip.com/Main/Detail.aspx?id=35849233 Wang, Z.H., Sun, S., Li, J.L., et al., 2003. Paleozoic Tectonic Evolution of the Northern Xinjiang, China: Geochemical and Geochronological Constraints from the Ophiolites. Tectonics, 22(2): 1-15. doi: 10.1029/2002tc001396 Windley, B., Kröner, A., Guo, J.H., et al., 2002. Neoproterozoic to Paleozoic Geology of the Altai Orogen, NW China: New Zircon Age Data and Tectonic Evolution. The Journal of Geology, 110(6): 719-737. doi: 10.1086/342866 Xiao, W.J., Han, C.M., Yuan, C., et al., 2008. Middle Cambrian to Permian Subduction-Related Accretionary Orogenesis of Northern Xinjiang, NW China: Implications for the Tectonic Evolution of Central Asia. Journal of Asian Earth Sciences, 32(2-4): 102-117. doi: 10.1016/j.jseaes.2007.10.008 Xiao, W.J., Kusky, T.M., 2009. Geodynamic Processes and Metallogenesis of the Central Asian and Related Orogenic Belts: Introduction. Gondwana Research, 16(2): 167-169. doi: 10.1016/j.gr.2009.05.001 Xiao, W.J., Zhang, L.C., Qin, K.Z., et al., 2004. Paleozoic Accretionary and Collisional Tectonics of the Eastern Tianshan (China): Implications for the Continental Growth of Central Asia. American Journal of Science, 304(4): 370-395. doi: 10.2475/ajs.304.4.370 Xiao, X.C., Tang, Y.Q., Feng, Y.M., et al., 1992. The Tectonism of Northern Xinjiang and Its Adjacent Region. Geological Publishing House, Beijing (in Chinese). Xiong, X.S., 2010. Moho Depth and Variation of the Continent in China and Its Geodynamic Implications (Dissertation). Chinese Academy of Geological Sciences, Beijing (in Chinese with English abstract). Xu, Z., Han, B.F., Ren, R., et al., 2012. Ultramafic-Mafic Melange, Island Arc and Post-Collisional Intrusions in the Mayile Mountain, West Junggar, China: Implications for Paleozoic Intra-oceanic Subduction-Accretion Process. Lithos, 132-133: 141-161. doi: 10.1016/j.lithos.2011.11.016 Yang, G.X., Li, Y.J., Gu, P.Y., et al., 2012. Geochronological and Geochemical Study of the Darbut Ophiolitic Complex in the West Junggar (NW China): Implications for Petrogenesis and Tectonic Evolution. Gondwana Research, 21(4): 1037-1049. doi: 10.1016/j.gr.2011.07.029 Zhang, J.E., Xiao, W.J., Han, C.M., et al., 2011a. A Devonian to Carboniferous Intra-oceanic Subduction System in Western Junggar, China. Lithos, 125(1-2): 592-606. doi: 10.1016/j.lithos.2011.03.013 Zhang, J.E., Xiao, W.J., Han, C.M., et al., 2011b. Kinematics and Age Constraints of Deformation in a Late Carboniferous Accretionary Complex in Western Junggar, NW China. Gondwana Research, 19(4): 958-974. doi: 10.1016/j.gr.2010.10.003 Zhang, L.F., Ai, Y.L., Li, X.P., et al., 2007. Triassic Collision of Western Tianshan Orogenic Belt, China: Evidence from SHRIMP U-Pb Dating of Zircons from HP/UHP Eclogitic Rocks. Lithos, 96(1-2): 266-280. doi: 10.1016/j.lithos.2006.09.012 Zhang, X.K., Qu, G.S., Zhao J.R., 2008. Seismic Detection of Deep Structures in Junggar Basin. Xinjiang Petroleum Geology, 29(6): 675-679 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-XJSD200806004.htm Zhang, Z.M., Liou, J.G., Coleman, R.G., 1984. An Outline of the Plate Tectonics of China. Geological Society of America Bulletin, 95(3): 295-312. doi: 10.1130/0016-7606(1984)95<295:aootpt>2.0.co;2 Zhou, J., Ji, J.Q., Han, B.F., et al., 2008. 40Ar/39Ar Geochronology of Mafic Dykes in North Xinjiang. Acta Petrologica Sinica, 24(5): 997-1010 (in Chinese with English abstract). http://www.zhangqiaokeyan.com/academic-journal-cn_acta-petrologica-sinica_thesis/0201252027464.html 艾可可, 季军良, 2015. 准噶尔西北部山地晚新生代以来隆升过程: 来自沉积学和磁组构的证据. 地球科学——中国地质大学学报, 40(3): 535-547. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX201503013.htm 白文吉, 杨经绥, 1985. 论大陆盆-山构造格局、盆地扩张及其形成机制. 长春地质学院学报, (4): 21-28. https://www.cnki.com.cn/Article/CJFDTOTAL-CCDZ198504003.htm 陈家富, 韩宝福, 张磊, 2010. 西准噶尔北部晚古生代两期侵入岩的地球化学Sr-Nd同位素特征及其地质意义. 岩石学报, 26(8): 2317-2335. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB201008009.htm 陈石, 郭召杰, 2010. 达拉布特蛇绿岩带的时限和属性以及对西准噶尔晚古生代构造演化的讨论. 岩石学报, 26(8): 2336-2344. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB201008010.htm 成守德, 王广瑞, 杨树德, 等, 1986. 新疆古板块构造. 新疆地质, 4(2): 1-26. https://www.cnki.com.cn/Article/CJFDTOTAL-XJDI198602000.htm 程裕淇, 沈永和, 张良臣, 等, 1995. 中国大陆的地质构造演化. 中国区域地质, (4): 289-294. https://www.cnki.com.cn/Article/CJFDTOTAL-ZQYD504.000.htm 杜劲松, 2014. 基于球坐标系的卫星磁异常数据处理与正反演方法研究(博士学位论文). 武汉: 中国地质大学. 方剑, 2006. 中国及邻区均衡重力异常及其地球动力学特征. 博士后研究工作报告, 北京: 中国地震局地质研究所. 冯益民, 1986. 西准噶尔蛇绿岩生成环境及其成因类型. 中国地质科学院西安地质矿产研究所所刊, (13): 37-45. https://www.cnki.com.cn/Article/CJFDTOTAL-XBFK198602003.htm 高睿, 肖龙, 王国灿, 等, 2013. 西准噶尔晚古生代岩浆活动和构造背景. 岩石学报, 29(10): 3413-3434. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB201310008.htm 郭飚, 刘启元, 陈九辉, 等, 2006. 中国境内天山地壳上地幔结构的地震层析成像. 地球物理学报, 49(6): 1693-1700. doi: 10.3321/j.issn:0001-5733.2006.06.016 韩宝福, 季建清, 宋彪, 等, 2006. 新疆准噶尔晚古生代陆壳垂向生长(Ⅰ)-后碰撞深成岩浆活动的时限. 岩石学报, 22(5): 1077-1086. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200605003.htm 何国琦, 李茂松, 刘德权, 1994. 中国新疆古生代地壳演化及成矿. 乌鲁木齐: 新疆人民出版社. 何国琦, 刘建波, 张越迁, 等, 2007. 准噶尔盆地西缘克拉玛依早古生代蛇绿混杂岩带的厘定. 岩石学报, 23(7): 1573-1576. doi: 10.3969/j.issn.1000-0569.2007.07.002 李锦轶, 肖序常, 汤耀庆, 等, 1990. 新疆东准噶尔卡拉麦里地区晚古生代板块构造的基本特征. 地质论评, 36(4): 305-316. doi: 10.3321/j.issn:0371-5736.1990.04.003 李锦轶, 肖序常, 汤耀庆, 等, 1992. 新疆北部金属矿产与板块构造. 新疆地质, 10(2): 138-146. https://www.cnki.com.cn/Article/CJFDTOTAL-XJDI199202005.htm 刘希军, 许继峰, 侯青叶, 等, 2007. 新疆东准噶尔克拉麦里蛇绿岩地球化学: 洋脊俯冲的产物. 岩石学报, 23(7): 1591-1602. doi: 10.3969/j.issn.1000-0569.2007.07.004 邱瑞照, 李文渊, 周肃. 等, 2008. 中国西北大陆岩石圈类型、岩石学结构及其意义. 西北地质, 41(2): 1-21. doi: 10.3969/j.issn.1009-6248.2008.02.001 童英, 王涛, 洪大卫, 等, 2010. 北疆及邻区石炭-二叠纪花岗岩时空分布特征及其构造意义. 岩石矿物学杂志, 29(6): 619-641. doi: 10.3969/j.issn.1000-6524.2010.06.003 肖序常, 汤耀庆, 冯益民, 等, 1992. 新疆北部及其邻区大地构造. 北京: 地质出版社. 熊小松, 2010. 中国大陆莫霍面深度与变化特征及其地球动力学意义(博士学位论文), 北京: 中国地质科学院. 张先康, 曲国胜, 赵金仁, 2008, 准噶尔盆地深部构造人工地震探测. 新疆石油地质, 29(6): 675-679. https://www.cnki.com.cn/Article/CJFDTOTAL-XJSD200806004.htm 周晶, 季建清, 韩宝福, 等, 2008. 新疆北部基性岩脉40Ar/39Ar年代学研究. 岩石学报, 24(5): 997-1010. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200805007.htm -
下载:
点击查看大图
图(4)
计量
- 文章访问数: 3735
- HTML全文浏览量: 636
- PDF下载量: 372
- 被引次数: 0
