DISTRIBUTION OF GUYOTS ON THE NORTHWESTERN SLOPE OF SOUTH CHINA SEA AND THEIR TOPOGRAPHIC FEATURES
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摘要:
西太平洋发育有大量的平顶海山，但在南海目前尚未见到关于平顶海山的详细报道。基于多波束测深数据，在南海西部陆坡识别出13个平顶海山和1个平顶海丘。平顶海山和海丘主要分布于西沙群岛和中沙群岛附近海底，以及海隆和海岭上。其中2个平顶海山为链状海山，位于中沙北海隆。南海西部陆坡的平顶海山和海丘山顶平台面积均超过3 km2，山顶水深范围184~631 m，位于陆坡中部的平顶海山和海丘山顶水深较小，而位于陆坡边缘的平顶海山山顶水深较大。通过对比西太平洋平顶海山，初步探讨了南海西部陆坡平顶海山和海丘地形特征指示的地质意义。
Abstract:The Ocean Drilling Program has made clear the internal structure of guyots in the west Pacific. However, little literatures are available in the region of the South China Sea concerning guyots or flat-top seamounts. Recently, on the northwestern slope of the South China Sea we have found nine flat-top seamounts and knolls exceeding 3 km2 in area based on multi-beam bathymetric data. In this paper, the topographic features of these guyotsare analyzed. It is found that they are mainly distributed on some topographic rises near submarine platforms submerged undera water depth of 184-631m. The most obvious one is the Pingnan Seamount to the north of the Zhongsha Islands. It consists of several small flat-top seamounts in a northwest line, rather similar tothe Megallan Seamounts in the West Pacific. According to the evolutionary model of theguyots in the west Pacific, the flat-top topographic featuresstarted from volcanic islands. They were erodedwhen they were close to the sea level, and coral reefs would develop to compensate the subsidence and made the top flat. Certainly the identification of flat-top seamounts and knolls in the South China Sea will help future geological and geophysical surveys in the region though the evolutionary details are not clear at present.
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Key words:
- South China Sea /
- northwestern slope /
- flat-top seamounts /
- topographic features
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表 1 研究区14个平顶海山和海丘的地形参数
Table 1. he terrain parameters of fourteen flat-top seamounts and knolls in the study area
序号 名称 位置 平面投影面积/km2 山顶平台面积/km2 山顶水深/m 基座水深/m 最大高差/m 走向 1 屏南海山 平顶山峰1 16°51.2′N 114°50.9′E 197 7.5 469 2 266 2 266 NW 平顶山峰2 16°49.5′N 114°56.9′E 202 12.5 498 2 409 2 409 平顶山峰3 16°45.0′N 114°58.5′E 103 2.0 568 2 327 2 327 平顶山峰4 16°39.2′N 115°04.3′E 138 7.3 585 2 476 2 476 2 隐矶海山 17°02.6′N, 115°21.9′E 364 3.6 631 3 951 3 320 E—W 3 排波海山 16°02.9′N, 113°53.8′E 284 12.3 357 2 416 2 059 NE 4 长风海山 13°38.7′N, 112°21.0′E 5 148 3.6 315 3 506 3 191 NE 5 赵述海山 17°22.5′N, 112°56.6′E 165 3.6 285 1 701 1 416 E—W 6 东岛海山 16°30.3′N, 112°57.0′E 74 8.3 282 1 288 1 006 NE 7 银砾海山 15°47.1′N, 112°41.5′E 190 10.4 276 2 328 2 052 NE 8 中建东海山 15°09.8′N, 111°54.1′E 121 4.6 184 1 448 1 264 NW 9 甘泉东海丘 16°52.6′N, 111°12.8′E 35 3.2 522 1 070 548 E—W 10 滟波海山 11°0.6′N, 110°16.2′E 204 14 541 1 550 1 009 NE 11 飞霜平顶海山 10°12.5′N, 110°42.3′E 946 40 482 3 380 2 898 NNW 12 江树海山 10°53.0′N, 111°11.8′E 1 789 4 615 3 890 3 275 NE 13 白沙平顶海山 09°57.4′N, 109°54.3′E 594 110 417 2 000 1 583 S—N 14 芳甸海山 10°09.8′N, 110°18.3′E 950 32 410 2 310 1 900 NE 
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[1] Flood P. Development of northwest Pacific guyots: General results from Ocean Drilling Program legs 143 and 144[J]. Island Arc, 1998, 8(1):92-98. https://cn.bing.com/academic/profile?id=10aa9f94486fe4463cb98b79b6bf688c&encoded=0&v=paper_preview&mkt=zh-cn
[2] Taylor B, Hayes D E. Origin and History of the South China Sea Basin[C]//Hayes D E. The Tectonics and Geological Evolution of Southeast Asia Seas and Islands, Part 2.American Geophysical Union, Geophysical Monograph, 1983, 27 : 23-56.
[3] Franke I, Savva D, Pubcllicr M, et al. The final rifting evolution in the South China Sea[J]. Marine and Petroleum Geology, 2014(58):704-720. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=84cf03738e5f31266e5d95ad8bc9642d
[4] Clift P D, Lin J, Barckhauscn U. Evidence of low flexural rigidity and low viscosity lower continental crust during continental break-up in the South China Sea[J]. Marine and Petroleum Geology, 2002, 19(8):951-970. doi: 10.1016/S0264-8172(02)00108-3
[5] 李家彪.南海大陆边缘动力学:科学实验与研究进展.地球物理学报[J].2011, 54(12):2993-3003. doi: 10.3969/j.issn.0001-5733.2011.12.002
[6] Briais A, Patriat P, Tapponnier P. Updated interpretation of magnetic anomalies and seafloor spreading stages in the South China Sea: implications for the tertiary tectonics of Southeast Asia[J]. Journal of Geophysical Research, 1993, 98(B4): 6299-6328. doi: 10.1029/92JB02280
[7] 姚伯初.中美合作调研南海地质专报[M].武汉:中国地质大学出版社, 1994.
[8] Hsu S K, Yeh Y, Doo W B, et al. New bathymetry and magnetic lineations identifications in the Northernmost South China Sea and their tectonic implications[J]. Marine Geophysical Research, 2004, 25(1):29-44. https://cn.bing.com/academic/profile?id=181709bb84d1cc069a2cc6073a483e64&encoded=0&v=paper_preview&mkt=zh-cn
[9] Li C F and Song T R.Magnetic recording of the Cenozoic oceanic crustal accretion and evolution of the South China Sea basin[J].Chinese Science Bulletin, 2012, 57(24):3165-3181. doi: 10.1007/s11434-012-5063-9
[10] Barckhausen U, Engels M, Franke D. et al. Evolution of the South China Sea: Revised ages for breakup and seafloor spreading[J]. Marine and Petroleum Geology, 2014, 58:599-611.
[11] Li C F, Xu X, Lin J, et al. Ages and magnetic structures of the South China Sea constrained by deep tow magnetic surveys and IODP Expedition 349[J]. Geochemistry Geophysics Geosystems, 2014, 15(12):4958-4983. doi: 10.1002/2014GC005567
[12] Koppers, A A P.On the 40Ar/39Ar dating of low-potassium ocean crust basalt from IODP Expedition 349, South China Sea[C].AGU Fall Meeting Abstracts, 2014.
[13] 修淳, 张道军, 翟世奎, 等.西沙岛礁基底花岗质岩石的锆石U-Pb年龄及其地质意义[J].海洋地质与第四纪地质, 2016, 36(3):115-126. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=hydzydsjdz201603014
[14] IHO, IOC. Standardization of Undersea Feature Names[M]. Monaco: Bathymetric Publication, 2008.
[15] 杨胜雄, 邱燕, 朱本铎.南海地质地球物理图系[M].北京:中国航海图书出版社, 2015.
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