CAJ | 학술논문

利用地震海洋学方法研究海洋内波已成为海洋地球物理学家与物理海洋学家共同关注的前沿问题.本文尝试利用当今时频分析的新手段--希尔伯特一黄变换中的经验模态分解(EMD)方法对南海东北部地震数据处理获得的垂直位移分布数据进行分解,获得了一些有新意的结果.分解结果表明,南海东北部海盆上方区域的内波包含波长约1.2、2.5、4、12.5 km的组成成分,其中波长约1.2、2.5 km的内波在200～1050 m的深度范围内上、下各层的波动基本耦合;波长约4 km与12.5 km的内波以600～700 m的水层为分界,其上、下部分的内波相位差90°,指示低波数内波能蜃的斜向传播.这些研究表明,EMD方法在内波运动学特征的地震海洋学研究方面有良好的应用前景.
이용지진해양학방법연구해양내파이성위해양지구물이학가여물리해양학가공동관주적전연문제.본문상시이용당금시빈분석적신수단--희이백특일황변환중적경험모태분해(EMD)방법대남해동북부지진수거처리획득적수직위이분포수거진행분해,획득료일사유신의적결과.분해결과표명,남해동북부해분상방구역적내파포함파장약1.2、2.5、4、12.5 km적조성성분,기중파장약1.2、2.5 km적내파재200～1050 m적심도범위내상、하각층적파동기본우합;파장약4 km여12.5 km적내파이600～700 m적수층위분계,기상、하부분적내파상위차90°,지시저파수내파능신적사향전파.저사연구표명,EMD방법재내파운동학특정적지진해양학연구방면유량호적응용전경.
Research on ocean internal waves by seismic oceanography is a frontier issue concerned by marine geophysicists and physical oceanographers. The paper applied Empirical Mode Decomposition (EMD) method of a new time-frequency analysis tool-Hilbert-Huang transform for studying vertical displacement data of internal waves in the northeastern South China Sea from seismic data and obtained new results. It showed that the internal waves above the central basin of South China Sea consist of components of different wavelength of around 1.2, 2.5, 4, 12.5 kin. The internal waves of the wavelength of 1.2 and 2.5 km are coupled between the upper and the lower part within the depth range of 200～1050 m, while the separated interface located at 600～700 m exists for the internal waves of the wavelength of around 4 and 12.5 km and the phase change is about 90° between the upper and the lower part, which infers oblique propagation of low wave-number internal waves energy. It inferred there is nice potential application of EMD method in seismic oceanography research.