Quantification and Unsupervised Clustering Analysis of Morphological Characteristics of Seamounts in South China Sea Basin
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摘要: 不同的火山喷发模式形成的海底火山在形态上存在差别，但由于缺乏有效方法，两者之间的关系仍不清晰.创新性地运用机器学习聚类分析法，基于高分辨率多波束水深数据，对南海海盆中的海山地形开展多维的形态参数量化分析，并对其结果进行无监督式聚类研究.结果表明，南海海盆中共发育三类海山：类型Ⅰ，体积大、坡度陡、底盘圆的大型孤立海山；类型Ⅱ，体积大、坡度缓、底盘长的大型线状海山；以及类型Ⅲ，体积小、坡度缓、底盘椭圆的小型海山.类型Ⅰ和Ⅱ位于东部次海盆洋中脊区，类型Ⅰ高耸的海山形态代表了活跃且快速的喷发模式，类型Ⅱ的平缓形态代表了缓慢且喷发物质流动性更强的火山活动，类型Ⅲ沿着转换断层及远离东部次海盆的洋中脊区，代表了缓慢且不强烈的火山活动.本文定量证实了不同构造背景下形成的海山形态具有普遍规律；针对海山形态学建立的聚类分析新方法，可为获得大量岩石学信息之前研究火山喷发模式提供新思路.Abstract: Morphological differences are evident among submarine volcanoes formed by varying eruption patterns. However, their interrelationship remains elusive due to methodological constraints. This study innovatively employs machine learning clustering analysis on high-resolution multibeam bathymetry data to quantitatively evaluate the morphological parameters of seamounts in the South China Sea Basin. The analysis discerns three distinct seamount types. Type Ⅰ: large, isolated seamounts characterized by significant volume, steep slopes, and rounded bases. Type Ⅱ: large, linear seamounts with substantial volume, gentle slopes, and elongated bases. Type Ⅲ: smaller seamounts with limited volume, gentle slopes, and elliptical bases. Type Ⅰ and Ⅱ seamounts are primarily found in the mid-ocean ridge zone of the eastern sub-basin. The pronounced morphology of Type Ⅰ suggests an active and rapid eruption regime, whereas Type Ⅱ's subdued form indicates slower volcanic activity with more fluidic lava flows. Conversely, Type Ⅲ, situated along the transform faults and distant from the mid-ocean ridge of the eastern sub-basin, signifies less intense volcanic activities. This research establishes a foundational understanding that seamount formations under distinct tectonic backgrounds follow general morphological patterns. The novel clustering approach proposed here offers fresh perspectives for probing volcanic eruption patterns, especially when extensive petrological data is not available.
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图 1 南海海盆多波束地形与区域地质特征
据Briais et al.，1993；Yan et al.，2008a；徐义刚等，2012；Barckhausen et al.，2014；杨胜雄等，2015；吴自银和温珍河，2021. 玄武岩定年结果和火成岩带的位置结果来自于Yan et al.，2008b，2014，2015；Li et al.，2015；Sibuet et al.，2016；Zhao et al.，2018
Fig. 1. Multibeam bathymetry and regional geological features of the South China Sea Basin
图 2 以中南海山为例，基于高精度多波束地形获取海山形态参数过程
a. 中南海山多波束地形；b. 海山山峰位置（红星标注）及最大高程；c. 利用最小二乘法拟合的海山椭圆锥体模型；d.部分形态参数测量示意图
Fig. 2. Using the Zhongnan Seamount as an example, the process of obtaining seamount morphological parameters based on high-precision multibeam bathymetry
图 4 南海重力异常分布图
a. 南海海盆的自由空间重力异常（Sandwell et al.，2014）；b. 根据图a计算的完整布格重力异常，以及扩张期后海山的空间分布.南海扩张期后的海山表现为自由空间重力异常大于30 mGal和布格重力异常小于300 mGal，这与Zhao et al.（2018）的观测结果一致
Fig. 4. Distribution of gravity anomalies in the South China Sea
图 5 珍贝‒黄岩海山链的多波束地形图
红色实线为海山长轴方向；黑色虚线为晚期扩张脊方向；红色和黑色虚线之间的夹角约为24°
Fig. 5. Multibeam bathymetry map of the Zhenbei-Huangyan Seamount Chain
图 6 聚类分析中分不同数量的簇(类)的平均轮廓系数
分2类和3类的轮廓系数得分明显高于其他分类数量，说明分2类和3类的效果更好.卫星高程地形数据的海山聚类效果讨论见4.3小节
Fig. 6. Average silhouette coefficient for different numbers of clusters in the clustering analysis
图 7 根据海山多波束地形分2类(a)和3类(b)的空间分布以及3类海山的对应几何学模型及实例(c)
分2类时可以有效区分大、小海山（图a），而分3类时，可在2类海山的基础上进一步区分出底座为长条形的海山（链）（图b、c）.标注为绿色的大型海山具有高程大、体积大、坡度陡、底面圆的特点，以中南海山为例（位置见图b中的Z1），主要沿着东部次海盆的残余洋中脊分布；标注为黄色的大型海山具有高程中等、体积较大、坡度平缓、底面为长条形的特点，以珍贝海山为例（位置见图b中的Z2），沿着东部次海盆的残余洋中脊分布；标注为紫色的小型海山具有高程小、体积小、底面呈圆形或椭圆形的特点，以一行海山为例（位置见图b中的Z3），在西北和西南次海盆内沿着残余洋中脊分布，在东部次海盆远离残余洋中脊分布
Fig. 7. Spatial distribution of seamounts based on multibeam bathymetry classified into 2 classes (a) and 3 classes (b), and the corresponding geometric models and examples for the 3 classes of seamounts (c)
图 8 基于海山多波束地形分3类的部分形态参数
a.体积与短轴之比；b. 体积与高程之比；c. 短轴坡角与体积之比；d. 长轴坡角与长轴之比；e. 底面积与高程之比；f. 长短轴之比与高程的比较；g. 高程与长轴的比较；h. 长轴坡角与长轴的比较；i. 长轴坡角与短轴的比较
Fig. 8. Selected morphological parameters for seamounts based on multibeam bathymetry classified into 3 classes
图 9 卫星数据与多波束数据获取的海山高程误差
a. 多波束数据提取的海山高程减去卫星数据提取的海山高程所得的高程误差分布图，图中正负数值分布的范围相近；b. 多波束数据减去卫星数据所得的高程误差与真实海山高程的二维直方图.误差集中在海山高程小于2.5 km的区域，且在0值两侧分布对称，表明卫星高程数据获得的海山高程被高估和低估的程度相近
Fig. 9. Seamount elevation errors between satellite-derived data and multibeam data
图 10 评估聚类分析效果的轮廓系数计算结果
a~d. 多波束地形的海山聚类效果评估；e~h. 卫星高程数据的聚类效果评估
Fig. 10. Calculation results of silhouette coefficients for evaluating the cluster analysis effectiveness
表 1 本研究统计的海山形态基本参数和计算方法
Table 1. Basic parameters of seamount morphology and calculation methods as compiled in this study
长轴方位 长轴大小 短轴大小 高程 长轴坡角 短轴坡角 长短轴之比 底面积 AZ(°) Max(km) Min(km) H0(m) Dip1(°) Dip2(°) Aspect ratio S(km2) 代表字母 a b c d e f g h 计算方法 拟合 拟合 拟合 拟合 Arctan(d/b) Arctan(d/c) b/c b$ \times $c$ \times $Π/4 
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表 2 各次海盆区域内的海山形态参数
Table 2. Seamount morphological parameters in each sub-basin
海山数量 体积总量(km3) 长轴方向 长轴平均值（km） 短轴平均值（km） 高程平均值（m） 长轴坡度平均值 短轴坡度平均值 长短轴之比平均值 底面积平均值（km2） 东部次海盆 25座 24 852 NE-SW: 10座 NW-SE: 14座 N-S: 1座 24.7 7.6 2 339 12.6° 23.7° 2.2 258 西南次海盆 24座 8 363.5 NE-SW: 9座 NW-SE: 12座 N-S: 1座 E-W: 2座 15.3 11.4 1 705 12.6° 24.5° 2.3 102.2 西北次海盆 4座 233.3 N-S: 1座 NE-SW: 2座 NW-SE: 1座 10.3 4.9 952 15° 22.4° 2 44.8
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Arabie, P., Hubert, L. J., 1996. An Overview of Combinatorial Data Analysis. In: Arabie, P., Hubert, L. J., De Soete, G., eds., Clusering and Classificaion. Word Scientific, Singapore, 5-63. https://doi.org/10.1142/9789812832153_0002 Barckhausen, U., Engels, M., Franke, D., et al., 2014. Evolution of the South China Sea: Revised Ages for Breakup and Seafloor Spreading. Marine and Petroleum Geology, 58: 599-611. https://doi.org/10.1016/j.marpetgeo.2014.02.022 Briais, A., Patriat, P., Tapponnier, P., 1993. Updated Interpretation of Magnetic Anomalies and Seafloor Spreading Stages in the South China Sea: Implications for the Tertiary Tectonics of Southeast Asia. Journal of Geophysical Research: Solid Earth, 98(B4): 6299-6328. https://doi.org/10.1029/92jb02280 Castruccio, A., Diez, M., Gho, R., 2017. The Influence of Plumbing System Structure on Volcano Dimensions and Topography. Journal of Geophysical Research: Solid Earth, 122(11): 8839-8859. https://doi.org/10.1002/2017JB014855 Chen, J., Zhu, B. D., Wen, N., et al., 2012. Gravity-Magnetic Response of the Islands and Seamounts of South China Sea. Chinese Journal of Geophysics, 55(9): 3152-3162 (in Chinese with English abstract). Chen, L., Wang, X., Liang, X. F., et al., 2020. Subduction Tectonics vs. Plume Tectonics—Discussion on Driving Forces for Plate Motion. Scientia Sinica Terrae, 50(4): 501-514 (in Chinese). Ding, W. W., Sun, Z., Dadd, K., et al., 2018. Structures within the Oceanic Crust of the Central South China Sea Basin and Their Implications for Oceanic Accretionary Processes. Earth and Planetary Science Letters, 488: 115-125. https://doi.org/10.1016/j.epsl.2018.02.011 Dingwell, D. B., 1996. Volcanic Dilemma—Flow or Blow? Science, 273(5278): 1054-1055. https://doi.org/10.1126/science.273.5278.1054 Francis, P., 1993. Volcanoes: A Planetary Perspective. Clarendon Press, New York. Kim, S. S., Wessel, P., 2011. New Global Seamount Census from Altimetry-Derived Gravity Data. Geophysical Journal International, 186(2): 615-631. https://doi.org/10.1111/j.1365-246X.2011.05076.x Kim, S. S., Wessel, P., 2015. Finding Seamounts with Altimetry-Derived Gravity Data. OCEANS 2015-MTS/IEEE. IEEE, Washington, D. C. . https://doi.org/10.23919/oceans.2015.7401883 Koppers, A. A. P., Watts, A. B., 2010. Intraplate Seamounts as a Window into Deep Earth Processes. Oceanography, 23(1): 42-57. https://doi.org/10.5670/oceanog.2010.61 Li, C. F., Xu, X., Lin, J., et al., 2014. Ages and Magnetic Structures of the South China Sea Constrained by Deep Tow Magnetic Surveys and IODP Expedition 349. Geochemistry, Geophysics, Geosystems, 15(12): 4958-4983. https://doi.org/10.1002/2014gc005567 Li, G., Zhang, L. L., Zhu, L., 2011. Research on the Tectonic Features and Gravity-Magnetic Characteristics of Continental Margins in the South China Sea. Progress in Geophysics, 26(3): 858-875 (in Chinese with English abstract). Li, J. B., Ding, W. W., Gao, J. Y., et al., 2011. Cenozoic Evolution Model of the Sea-Floor Spreading in South China Sea: New Constraints from High Resolution Geophysical Data. Chinese Journal of Geophysics, 54(12): 3004-3015 (in Chinese with English abstract). doi: 10.3969/j.issn.0001-5733.2011.12.003 Li, S. Z., Zhao, S. J., Liu, X., et al., 2014. Ocean-Continent Transition and Coupling Processes. Periodical of Ocean University of China, 44(10): 113-133 (in Chinese with English abstract). Li, X. H., Li, J. B., Yu, X., et al., 2015. 40Ar/39Ar Ages of Seamount Trachytes from the South China Sea and Implications for the Evolution of the Northwestern Sub-Basin. Geoscience Frontiers, 6(4): 571-577. https://doi.org/10.1016/j.gsf.2014.08.003 MacQueen, J., 1967. Some Methods for Classification and Analysis of Multivariate Observations. In: The Fifth Berkeley Symposium on Mathematical Statistics and Probability. University of California Press, Berkeley, 281-297. Maire, E., Lelièvre, E., Brau, D., et al., 2000. Development of an Ultralow-Light-Level Luminescence Image Analysis System for Dynamic Measurements of Transcriptional Activity in Living and Migrating Cells. Analytical Biochemistry, 280(1): 118-127. https://doi.org/10.1006/abio.2000.4503 Meyer, F., 1979. Iterative Image Transformations for an Automatic Screening of Cervical Smears. Arthropod Structure & Development, 27(1): 128-135. https://doi.org/10.1177/27.1.438499 Morgan, W. J., 1971. Convection Plumes in the Lower Mantle. Nature, 230(5288): 42-43. https://doi.org/10.1038/230042a0 Papale, P., 1999. Strain-Induced Magma Fragmentation in Explosive Eruptions. Nature, 397(6718): 425-428. https://doi.org/10.1038/17109 Peng, X., Li, C. F., Song, T. R., et al., 2022. Deep Structures and Lithospheric Breakup Processes at Northern Continent-Ocean Transition Zone of the South China Sea. Earth Science, 47(11): 4245-4255 (in Chinese with English abstract). Ren, J. Y., 2018. Genetic Dynamics of China Offshore Cenozoic Basins. Earth Science, 43(10): 3337-3361 (in Chinese with English abstract). Robinson, J. E., Eakins, B. W., 2006. Calculated Volumes of Individual Shield Volcanoes at the Young End of the Hawaiian Ridge. Journal of Volcanology and Geothermal Research, 151(1-3): 309-317. https://doi.org/10.1016/j.jvolgeores.2005.07.033 Sandwell, D. T., Müller, R. D., Smith, W. H. F., et al., 2014. New Global Marine Gravity Model from CryoSat-2 and Jason-1 Reveals Buried Tectonic Structure. Science, 346(6205): 65-67. https://doi.org/10.1126/science.1258213 Sandwell, D. T., Goff, J. A., Gevorgian, J., et al., 2022. Improved Bathymetric Prediction Using Geological Information: Synbath. Earth and Space Science, 9(2): e02069. https://doi.org/10.1029/2021ea002069 Sibuet, J. C., Yeh, Y. C., Lee, C. S., 2016. Geodynamics of the South China Sea. Tectonophysics, 692: 98-119. https://doi.org/10.1016/j.tecto.2016.02.022 Smith, D. K., 1988. Shape Analysis of Pacific Seamounts. Earth and Planetary Science Letters, 90(4): 457-466. https://doi.org/10.1016/0012-821X(88)90143-4 Song, X., Li, C., Yao, Y., et al. 2017. Magmatism in the Evolution of the South China Sea: Geophysical Characterization. Marine Geology, 394(1): 4-15. https://doi.org/10.1016/j.margeo.2017.07.021 Sparks, R. S. J., 2003. Dynamics of Magma Degassing. Geological Society, London, Special Publications, 213(1): 5-22. https://doi.org/10.1144/gsl.sp.2003.213.01.02 Sun, Z., Ding, W. W., Zhao, X. X., et al., 2019. The Latest Spreading Periods of the South China Sea: New Constraints from Macrostructure Analysis of IODP Expedition 349 Cores and Geophysical Data. Journal of Geophysical Research: Solid Earth, 124(10): 9980-9998. https://doi.org/10.1029/2019jb017584 Tibaldi, A., 1995. Morphology of Pyroclastic Cones and Tectonics. Journal of Geophysical Research: Solid Earth, 100(B12): 24521-24535. https://doi.org/10.1029/95jb02250 Tozer, B., Sandwell, D. T., Smith, W. H. F., et al., 2019. Global Bathymetry and Topography at 15 ArcSec: SRTM15+. Earth and Space Science, 6(10): 1847-1864. https://doi.org/10.1029/2019ea000658 Unger Moreno, K. A., Thal, J., Bach, W., et al., 2021. Volcanic Structures and Magmatic Evolution of the Vesteris Seamount, Greenland Basin. Frontiers in Earth Science, 9: 1-14. https://doi.org/10.3389/feart.2021.711910 Wu, Z. Y., Wen, Z. H., 2021. Marine Geology of China Sea. Science Press, Beijing (in Chinese). Xu, H. H., Ma, H., Song, H. B., et al., 2011. Numerical Simulation of Eastern South China Sea Basin Expansion. Chinese Journal of Geophysics, 54(12): 3070-3078 (in Chinese with English abstract). Xu, Y. G., Wei, J. X., Qiu, H. N., et al., 2012. Opening and Evolution of the South China Sea Constrained by Studies on Volcanic Rocks: Preliminary Results and a Research Design. Chinese Science Bulletin, 57(20): 1863-1878 (in Chinese). doi: 10.1360/csb2012-57-20-1863 Xu, Z. Y., Wang, J., Yao, Y. J., et al., 2021. The Temporal-Spatial Distribution and Deep Structure of the Zhongnan-Liyue Fault Zone in the North of the South China Sea Basin. Earth Science, 46(3): 942-955 (in Chinese with English abstract). Yan, P., Wang, Y. L., Liu, H. L., 2008a. Post-Spreading Transpressive Faults in the South China Sea Basin. Tectonophysics, 450(1-4): 70-78. https://doi.org/10.1016/j.tecto.2008.01.015 Yan, Q. S., Shi, X. F., Yang, Y. M., et al., 2008b. Potassium-Argon/Argon-40-Argon-39 Geochronology of Cenozoic Alkali Basalts from the South China Sea. Acta Oceanologica Sinica, 27(6): 115-123. Yan, Q. S., Castillo, P., Shi, X. F., et al., 2015. Geochemistry and Petrogenesis of Volcanic Rocks from Daimao Seamount (South China Sea) and Their Tectonic Implications. Lithos, 218: 117-126. https://doi.org/10.1016/j.lithos.2014.12.023 Yan, Q. S., Shi, X. F., 2007. Hainan Mantle Plume and the Formation and Evolution of the South China Sea. Geological Journal of China Universities, 13(2): 311-322 (in Chinese with English abstract). Yan, Q. S., Shi, X. F., Castillo, P. R., 2014. The Late Mesozoic-Cenozoic Tectonic Evolution of the South China Sea: A Petrologic Perspective. Journal of Asian Earth Sciences, 85: 178-201. https://doi.org/10.1016/j.jseaes.2014.02.005 Yan, Q. S., Shi, X. F., Metcalfe, I., et al., 2018. Hainan Mantle Plume Produced Late Cenozoic Basaltic Rocks in Thailand, Southeast Asia. Scientific Reports, 8(1): 2640. https://doi.org/10.1038/s41598-018-20712-7 Yang, S. X., Qiu, Y., Zhu, B. D., et al., 2015. Geologic and Geophysical Atlas of the South China Sea. China Navigation Charts Press, Tianjin (in Chinese). Yang, S. Y., Fang, N. Q., Yang, S. X., et al., 2011. A Further Discussion on Formation Background and Tectonic Constraints of Igneous Rocks in Central Sub-Basin of the South China Sea. Earth Science, 36(3): 455-470 (in Chinese with English abstract). Yao, B. C., 1995. Characteristics and Tectonic Significance of the Zhongnan-Liyue Fault. Research of Geological South China Sea, 1-14 (in Chinese). Zhang, C. M., Sun, Z., Zhao, M. H., et al., 2022. Crustal Structure and Tectono-Magmatic Evolution of Northern South China Sea. Earth Science, 47(7): 2337-2353 (in Chinese with English abstract). Zhang, G. L., Luo, Q., Zhao, J., et al., 2018. Geochemical Nature of Sub-Ridge Mantle and Opening Dynamics of the South China Sea. Earth and Planetary Science Letters, 489: 145-155. https://doi.org/10.1016/j.epsl.2018.02.040 Zhao, D. P., 2007. Seismic Images under 60 Hotspots: Search for Mantle Plumes. Gondwana Research, 12(4): 335-355. https://doi.org/10.1016/j.gr.2007.03.001 Zhao, M. H., He, E. Y., Sibuet, J. C., et al., 2018. Postseafloor Spreading Volcanism in the Central East South China Sea and Its Formation through an Extremely Thin Oceanic Crust. Geochemistry, Geophysics, Geosystems, 19(3): 621-641. https://doi.org/10.1002/2017gc007034 Zhao, M. H., Qiu, X. L., Xu, H. L., et al., 2011. Deep Seismic Surveys in the Southern South China Sea and Contrast on Its Conjugate Margins. Earth Science, 36(5): 823-830 (in Chinese with English abstract). Zhao, Y. H., Ding, W. W., Yin, S. R., et al., 2020. Asymmetric Post-Spreading Magmatism in the South China Sea: Based on the Quantification of the Volume and Its Spatiotemporal Distribution of the Seamounts. International Geology Review, 62(7/8): 955-969. https://doi.org/10.1080/00206814.2019.1577189 陈洁, 朱本铎, 温宁, 等, 2012. 南海海岛海山的重磁响应特征. 地球物理学报, 55(9): 3152-3162. 陈凌, 王旭, 梁晓峰, 等, 2020. 俯冲构造vs. 地幔柱构造——板块运动驱动力探讨. 中国科学: 地球科学, 50(4): 501-514. 李刚, 张丽莉, 朱鲁, 2011. 南海大陆边缘构造活动与重磁场特征研究. 地球物理学进展, 26(3): 858-875. 李家彪, 丁巍伟, 高金耀, 等, 2011. 南海新生代海底扩张的构造演化模式: 来自高分辨率地球物理数据的新认识. 地球物理学报, 54(12): 3004-3015. doi: 10.3969/j.issn.0001-5733.2011.12.003 李三忠, 赵淑娟, 刘鑫, 等, 2014. 洋‒陆转换与耦合过程. 中国海洋大学学报(自然科学版), 44(10): 113-133. 彭希, 李春峰, 宋陶然, 等, 2022. 南海北部洋‒陆过渡带深部结构与岩石圈破裂过程. 地球科学, 47(11): 4245-4255. doi: 10.3799/dqkx.2022.366 任建业, 2018. 中国近海海域新生代成盆动力机制分析. 地球科学, 43(10): 3337-3361. doi: 10.3799/dqkx.2018.330 吴自银, 温珍河, 2021. 中国近海海洋地质. 北京: 科学出版社. 许鹤华, 马辉, 宋海斌, 等, 2011. 南海东部海盆扩张过程的数值模拟. 地球物理学报, 54(12): 3070-3078. 徐义刚, 魏静娴, 邱华宁, 等, 2012. 用火山岩制约南海的形成演化: 初步认识与研究设想. 科学通报, 57(20): 1863-1878. 徐子英, 汪俊, 姚永坚, 等, 2021. 中南‒礼乐断裂带在南海海盆北部的时空展布与深部结构. 地球科学, 46(3): 942-955. 鄢全树, 石学法, 2007. 海南地幔柱与南海形成演化. 高校地质学报, 13(2): 311-322. 杨胜雄, 邱燕, 朱本铎, 等, 2015. 南海地质地球物理图系. 天津: 中国航海图书出版社. 杨蜀颖, 方念乔, 杨胜雄, 等, 2011. 关于南海中央次海盆海山火山岩形成背景与构造约束的再认识. 地球科学, 36(3): 455-470. doi: 10.3799/dqkx.2011.048 姚伯初, 1995. 中南‒礼乐断裂的特征及其构造意义. 南海地质研究, 1-14. 张翠梅, 孙珍, 赵明辉, 等, 2022. 南海北部陆缘结构及构造‒岩浆演化. 地球科学, 47(7): 2337-2353. doi: 10.3799/dqkx.2021.208 赵明辉, 丘学林, 徐辉龙, 等, 2011. 南海南部深地震探测及南北共轭陆缘对比. 地球科学, 36(5): 823-830. doi: 10.3799/dqkx.2011.085 -
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