南海高分辨率岩石圈有效弹性厚度及其影响因素分析  

High-resolution effective elastic thicknesses of the lithospherein the South China Sea and their controlling factors

作　　者：李志康 李春峰[1,2] 朱塽 黄亮 刘文潇[3,4] Li Zhikang;Li Chunfeng;Zhu Shuang;Huang Liang;Liu Wenxiao(Ocean College,Zhejiang University,Zhoushan,Zhejiang 316021,China;Hainan Institute,Zhejiang University,Sanya,Hainan 572025,China;South China Sea Marine Survey and Technology Center,State Oceanic Administration,Guangzhou,Guangdong 510300,China;Key Laboratory of Marine Environmental Survey Technology and Application,Ministry of Natural Resources,Guangzhou,Guangdong 510300,China)

机构地区：[1]浙江大学海洋科学系,浙江舟山316021 [2]海南浙江大学研究院,海南三亚572025 [3]国家海洋局南海调查技术中心,广东广州510300 [4]自然资源部海洋环境探测技术与应用重点实验室,广东广州510300

出　　处：《地质学报》2022年第8期2670-2682,共13页Acta Geologica Sinica

基　　金：国家自然科学基金项目(编号41776057,42176055);海南省自然科学基金创新研究团队项目(编号421CXTD441)联合资助的成果。

摘　　要：南海构造环境复杂,海盆内海山规模不一,为了探究南海岩石圈强度的影响因素及其与海山演化的联系,本文利用Parker Oldenburg法计算得到地壳密度分布并结合基于小波变换的导纳法计算南海岩石圈有效弹性厚度(简称T_(e)),提高了计算结果的准确度和分辨率。南海大洋岩石圈T_(e)整体较小,分布在0~16 km范围内。南海T_(e)与居里点深度和热流点相关性高,说明岩石圈强度受温度结构影响强烈,海山T_(e)值与海山加载时岩石圈年龄未表现出相关性,表明岩浆活动等热异常会削弱岩石圈强度。The South China Sea(SCS)has experienced complex thermal and dynamic evolution,with the loading of numerous seamounts in the central basin.To explore the controlling factors of lithospheric strength and their relationship with seamount evolution in SCS,we first calculate the density distribution of the crust using the Parker Oldenburg method and then apply it to estimate the spatial variations of effective elastic thickness of the lithosphere(T_(e))with the‘fan’wavelet admittance method.T_(e)in oceanic lithosphere is relatively low and mainly distributed in the range of 0~16 km.T_(e)is correlated positively with curie point depth and negatively with surface heat flow,indicating a strong influence of geotherm on T_(e).However,T_(e)of the seamounts show no correction with the time of loading,indicating strong magmatism and thermal anomalies weakened the lithosphere around seamounts.

关 键 词：有效弹性厚度 南海 海山 居里面 热结构 Parker-Oldenburg法 

分 类 号：P736[天文地球—海洋地质]