Journal of Tropical Oceanography >
Grain size characteristics and influencing factors of terrigenous sediment in the deep-sea basin of the northeastern South China Sea since the Last Glacial Maximum
Copy editor: YAO Yantao
Received date: 2021-02-26
Revised date: 2021-04-20
Online published: 2021-04-29
Supported by
The 2020 Research Program of Sanya Yazhou Bay Science and Technology City(SKJC-2020-01-012)
National Natural Science Foundation of China(41976065)
National Natural Science Foundation of China(41776061)
Pearl River S&T Nova Program of Guangzhou(201906010050)
Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou)(GML2019ZD0104)
A number of factors control the evolution of deep-sea currents in the northeastern South China Sea (SCS), but there is still a lack of deep understanding of sensitive indicators, evolution processes and controlling factors of the bottom currents since the Last Glacial Maximum (LGM). We selected the 16ZBS11 core in the deep-sea basin of the northeastern SCS to analyze the grain size and age of the terrigenous sediment. The environmental sensitivity factors were extracted by the grain size-standard deviation method; at the same time, the bottom current intensity and transport capacity were calculated. Our results show that the terrigenous debris in the study area are mainly composed of silt and clay; sandy components only appear in a few layers. The deep-sea sedimentary environment evolution in the northern SCS has gone through three stages: stage Ⅰ: 22.39~16.02 ka BP; stage Ⅱ: 16.02~9.58 ka BP; stage Ⅲ: 9.58 ka BP to present. Interestingly, the components of clay and silt in each evolution stage evoluted in reverse phase. The intensity and transport capacity of the bottom current have decreased gradually since the LGM and changed synchronously. At about 16 ka BP and 11.5 ka BP, the SCS was connected with the Indian Ocean and the Taiwan Strait, respectively, which affected the oceanic processes in the northern SCS. In particular, the changes of mixing patterns and intensities in the northern SCS since 9.58ka BP, profoundly affected the deep-sea terrigenous sediment transport and sedimentary evolution. Our results provide a new understanding of the evolution of bottom current activities in the northern SCS, and new evidence for deep-sea processes in the SCS.
WANG Xuesong , CHEN Zhong , XU Antao , TIAN Yuhang , CAO Li , ZHANG Bin . Grain size characteristics and influencing factors of terrigenous sediment in the deep-sea basin of the northeastern South China Sea since the Last Glacial Maximum[J]. Journal of Tropical Oceanography, 2022 , 41(1) : 158 -170 . DOI: 10.11978/2021027
图1 16ZBS11岩心位置(a)及西太平洋128°E剖面中深层水团概念模式图(b)图a基于国家测绘地理信息局标准地图服务网站下载的审图号为 GS(2016)1560 号的标准地图制作, 图中红色五角星为本文研究的岩心站位, 黑色实心圆点为文中提及站位, 包括10E203(Zheng et al, 2016)、16602-4(Liu et al, 2017)和MD12-3428、MD12-3433、MD12-3434(Zhao et al, 2017); 图b参考Wu等(2015)和Zhong等(2019), 剖面位置见图a黑色线 Fig. 1 Research station 16ZBS11 (a), and the modern conceptual model diagram of the mid-deep water at the 128°E section of the western Pacific Ocean (b) |
表1 16ZBS11岩心的AMS14C测年结果Tab. 1 AMS14C radiocarbon dates for samples from core 16ZBS11 |
层位/cm | 测试材料 | AMS14C年龄 /a BP | 校正年龄 /Cal. a BP | 年龄范围 /a BP( ±1σ) |
---|---|---|---|---|
9~10 | 有孔虫混合种 | 2290±30 | 1726 | 1567~1877 |
59~60 | 有孔虫混合种 | 7080±30 | 7385 | 7247~7518 |
161~162 | 有孔虫混合种 | 12920±40 | 14603 | 14299~14882 |
279~280 | 有孔虫混合种 | 17170±50 | 19825 | 19554~20089 |
图3 16ZBS11岩心及其周边站位的沉积速率对比16ZBS11为本文数据, 10E203据Zheng等(2016), 16602-4据Liu等(2017), MD12-3428、MD12-3433、MD12-3434据Zhao等(2017) Fig. 3 Sediment accumulation rates of core 16ZBS11 and nearby sites 10E203 from Zheng et al (2016), 16602-4 from Liu et al (2017), and MD12-3428, MD12-3433 and MD12-3434 from Zhao et al (2017) |
表2 16ZBS11岩心的陆源碎屑粒度组成及各阶段粒度参数特征Tab. 2 Terrigenous detrital grain size composition of core 16ZBS11 and characteristics of grain size parameters at each stage |
砂/% | 粉砂/% | 粘土/% | 平均粒径/μm | 中值粒径/μm | 偏态值SKI | 峰态值KG | 分选系数σi | ||
---|---|---|---|---|---|---|---|---|---|
阶段Ⅰ | 最大值 | 1.45 | 70.84 | 35.58 | 6.42 | 6.69 | -0.06 | 1.14 | 1.43 |
最小值 | 0.00 | 64.42 | 28.99 | 5.24 | 5.40 | -0.12 | 1.09 | 1.23 | |
平均值 | 0.31 | 67.13 | 32.59 | 5.78 | 6.01 | -0.10 | 1.11 | 1.36 | |
阶段Ⅱ | 最大值 | 1.63 | 67.44 | 41.73 | 5.87 | 6.07 | -0.04 | 1.15 | 1.42 |
最小值 | 0.00 | 58.28 | 32.24 | 4.43 | 4.69 | -0.16 | 1.08 | 1.16 | |
平均值 | 0.31 | 62.76 | 37.12 | 5.06 | 5.28 | -0.11 | 1.11 | 1.27 | |
阶段Ⅲ | 最大值 | 0.81 | 64.48 | 42.24 | 5.45 | 5.65 | -0.07 | 1.15 | 1.37 |
最小值 | 0.00 | 57.76 | 34.75 | 4.40 | 4.65 | -0.15 | 1.09 | 1.15 | |
平均值 | 0.10 | 61.68 | 38.27 | 4.85 | 5.09 | -0.12 | 1.11 | 1.23 |
图7 16ZBS11岩心的敏感粒级组分及底流搬运强度指标图中的Ⅰ、Ⅱ、Ⅲ为沉积阶段; Holocene: 全新世; PB: 前北方期; YD: 新仙女木期; B/A: 布林-阿勒罗德期; H1: 海因里希事件1期; LGM: 末次冰盛期; 彩色曲线为5点移动平均值 Fig. 7 Sensitive grain fractions and bottom-current transport intensity index of core 16ZBS11. Ⅰ, Ⅱ, and Ⅲ indicate sedimentary stages. PB, YD, B/A, HS1, and LGM refer to Preboreal, Younger Dryas, Bølling-Allerød, Heinrich Stadial 1, and Last Glacial Maximum identified in core 16ZBS11, respectively. The color curves are five-point moving average curves |
图8 南海北部海平面变化及底流强度指标对比图a Comparison of sea-level changes and bottom-current transport intensity index in the northern SCS |
*感谢所有对本文付出努力的人, 感谢各位审稿专家对本文提出的宝贵建议, 感谢中国科学院南海海洋研究所“实验1”号科学考察船提供研究样品。
[1] |
黄维, 汪品先, 1998. 末次冰期以来南海深水区的沉积速率[J]. 中国科学 D辑: 地球科学, 28(1): 13-17.
|
[2] |
黄维, 汪品先, 2006. 渐新世以来的南海沉积量及其分布[J]. 中国科学 D辑: 地球科学, 36(9): 822-829.
|
[3] |
翦知湣, 田军, 黄维, 等, 2020. 南海海盆演变与深部海流[J]. 科技导报, 38(18): 52-56.
|
[4] |
蓝东兆, 张维林, 陈承惠, 等, 1993. 晚更新世以来台湾海峡西部的海侵及海平面变化[J]. 海洋学报, 15(4): 77-84.
|
[5] |
李丽, 徐沁, 2017. 上新世以来巽他陆架海平面变化研究[J]. 地球科学进展, 32(11): 1126-1136.
|
[6] |
李亮, 陈忠, 刘建国, 等, 2014. 南海北部表层沉积物类型及沉积环境区划[J]. 热带海洋学报, 33(1): 54-61.
|
[7] |
李平原, 路剑飞, 夏真, 等, 2020. 南海北部陆坡30 ka以来的沉积环境演变[J]. 海洋地质与第四纪地质, 40(6): 14-21.
|
[8] |
刘志飞, 李夏晶,
|
[9] |
刘志飞, 张艳伟, 赵玉龙, 2020. 深海风暴的原位观测[J]. 科技导报, 38(18): 26-29.
|
[10] |
邵磊, 李学杰, 耿建华, 等, 2007. 南海北部深水底流沉积作用[J]. 中国科学 D辑: 地球科学, 37(6): 771-777.
|
[11] |
石学法, 乔淑卿, 杨守业, 等, 2021. 亚洲大陆边缘沉积学研究进展(2011-2020)[J]. 矿物岩石地球化学通报, 40(2): 319-336.
|
[12] |
孙有斌, 高抒, 李军, 2003. 边缘海陆源物质中环境敏感粒度组分的初步分析[J]. 科学通报, 48(1): 83-86.
|
[13] |
田纪伟, 曲堂栋, 2012. 南海深海环流研究进展[J]. 科学通报, 57(20): 1827-1832.
|
[14] |
王东晓, 王强, 蔡树群, 等, 2019. 南海中深层动力格局与演变机制研究进展[J]. 中国科学 D辑: 地球科学, 49(12): 1919-1932.
|
[15] |
王桂华, 田纪伟, 2020. 南海深层水的来龙去脉[J]. 科技导报, 38(18): 21-25.
|
[16] |
汪品先, 2020. 南海深部过程的探索[J]. 科技导报, 38(18): 6-20.
|
[17] |
王树民, 陈泓君, 钟和贤, 2001. 南海东北部晚第四纪地层不整合的发现及其地质意义[J]. 南海地质研究, 1(10): 55-61.
|
[18] |
张兰兰, 陈木宏, 陈忠, 等, 2010. 南海表层沉积物中的碳酸钙含量分布及其影响因素[J]. 地球科学--中国地质大学学报, 35(6): 891-898.
|
[19] |
赵绍华, 刘志飞, 陈全, 等, 2017. 南海北部末次冰期以来深水沉积物组成及其堆积速率的时空变化特征[J]. 中国科学 D辑: 地球科学, 47(8): 958-971.
|
[20] |
钟广法, 朱本铎, 王嘹亮, 2020. 南海浊流地貌[J]. 科技导报, 38(18): 75-82.
|
[21] |
|
[22] |
|
[23] |
|
[24] |
|
[25] |
|
[26] |
|
[27] |
|
[28] |
|
[29] |
|
[30] |
|
[31] |
|
[32] |
|
[33] |
|
[34] |
|
[35] |
|
[36] |
|
[37] |
|
[38] |
|
[39] |
|
[40] |
|
[41] |
|
[42] |
|
[43] |
|
[44] |
|
[45] |
|
[46] |
|
[47] |
|
[48] |
|
[49] |
|
[50] |
|
[51] |
|
[52] |
|
[53] |
|
[54] |
|
[55] |
|
[56] |
|
[57] |
|
[58] |
|
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