申文斌,邱鹏,李江涛,盛敏汉,张箫,李赛红

• 1:武汉大学测绘学院

摘要(Abstract)：

探测Slichter模态三重分裂可有效约束内核密度、内核半径及内外核边界密度跳跃。虽然Smylie(1992)声称探测到了Slichter模态三重分裂,但至今未被国际学术界公认。本文结合一个实验算例,阐述了Hilbert-Huang变换(HHT)分析方法的核心思想,并将该方法应用于探测Slichter模三重分裂谱线的研究。我们选取了全球分布的8个台站连续记录两年的小时间隔超导重力数据,进行了潮汐和气压改正后,将它们叠加获得重力残差;然后对重力残差作HHT分析,得到能量谱,进而选出了12种可能的谱峰组合,其中两组结果与Smylie的结果很接近,且本文得到的谱峰分裂相比于Smylie的结果具有更好的对称性。

关键词(KeyWords)： HHT;Slichter模;三重谱线;能量谱

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(41174011;40974015),国家自然科学基金创新群体(41021061)

作者(Author): 申文斌,邱鹏,李江涛,盛敏汉,张箫,李赛红

DOI: 10.16251/j.cnki.1009-2307.2012.06.033

参考文献(References)：

• [1]Slichter L B The Fundamental Free Mode of the Earth’sInner Core[C]//Proc.Natl.Acad.Sci.,1961,47(2):186-190.
• [2]Smylie D E The Inner Core Translational Triplet and theDensity near Earth’s Center[J].Science,1992,255:1678-1682.
• [3]Smylie D E,Hinderer J,Richter B,et al.The ProductSpectra of Gravity and Barometric Pressure in Europe[J].Phys Earth Planet Inter,1993,80:135-157.
• [4]Smylie D E,Jiang X.Core Oscillations and Their Detectionin Superconducting Gravimeter Records[J].J GeomagGeoeletr,1993,45:1347-1369.
• [5]Smylie D E,McMillan D G.Viscous and Rotational Split-ting of the Translational Oscillations of Earth’s Solid In-ner Core[J].Phys.Earth Planet.Int.,1998,106:1-18.
• [6]Smylie D E.Viscosity near Earth’s Solid Inner Core[J].Science,1999,284:461-463.
• [7]Smylie D E,MacMillan D G.The Inner Core as a DynamicViscometer[J].Geophysics of the Earth and Planetary In-teriors,2000,117:71-79.
• [8]Courtier N,Ducarme B,Goodkind J,et al.Global Super-conducting Gravimeter Observations and the Search for theTranslational Modes of the Inner Core[J].Phys.EarthPlanet.Int.,2000,117:3-20.
• [9]Roult G,Roch J,Eric C.Observation of Split Modes fromthe 26th December 2004 Sumatra-Andaman Mega-event[J].Physics of the Earth and Planetary Interiors,2010,179:45-59.
• [10]Widmer-Schnidrig R.What Can Super-conducting Gravim-eters Contribute to Normal-Mode Seismology[J]Bulletinof the Seismological Society of America,2003,93(3):
• [11]徐建桥,孙和平,傅容珊.地球固体内核平动振荡的研究和检测[J].地球科学进展,2005,20(7):740-745.
• [12]Huang N E,Shen Z,et al.The Empirical Mode Decompo-sition and the Hilbert Spectrum for Nonlinear and Non-sta-tionary Time Series Analysis[C]//Proc.R.Soc.Lond.A,1998,454:903-995.
• [13]Huang N.E.,Shen Z.,and Steven R.L..A New View ofNonlinear Water Waves:The Hilbert Spectrum[J].An-nu.Rev.Fluid Mech,1999,31:417-457.
• [14]Huang N E,Chern C C,Huang K,et al.A New SpectralRepresentation of Earthquake Data:Hilbert Spectral Anal-ysis of Station TCU129,Chi-Chi,Taiwan,21 September1999[J].Bulletin of the Seismological Society of Ameri-ca,2001,91(5):1310-1338.
• [15]Huang N E,Wu Z.A Review on Hilbert-Huang Trans-form:Method and Its Applications to Geophysical Studies[J].Rev.Geophys.,2008,46:12-17.
• [16]公茂盛,谢礼立.HHT方法在地震工程中的应用之初步探讨[J].世界地震工程,2003,19(3):39-43.
• [17]孙列.基于Hilbert-黄变换(HHT)的地震作用结构损伤识别[D].杭州:浙江大学,2007:28-30.