基于重力数据反演南海及邻区莫霍面深度分布特征
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摘要
采用重力异常数据,在频率域内通过Parker-Oldenburg反演算法计算南海及邻区的莫霍面深度。通过EGM2008重力场模型联合GOCE重力场模型,计算研究区的自由空气重力异常;通过重力场分离,得到莫霍面起伏引起的重力异常,用于反演莫霍面深度。计算结果与地震剖面计算的莫霍面深度结果平均偏差1.59 km,标准偏差1.9 km。结果表明,南海及邻区的莫霍面深度分布具有明显的区域化构造特征。
Gravity inversion can be used to determine Moho depths in sea regions where we lack adequate seismic information. In this study, the gravity anomaly is used to calculate the Moho depths of the South China Sea and adjacent regions. After isolating the gravity anomaly of Moho depths from the free-air gravity anomalies, the resulting gravity residual is used to invert the Moho depths based on Parker-Oldenburg inversion algorithm. To eliminate the high-frequency oscillations that occured in the inversion process, a cosine filter for gravity data filtering in wave number domain is applied, where smaller and greater frequency parameters are estimated from the energy spectrum of the residual gravity anomaly. The average difference in Moho depths between this study and the seismic measurement results is 1.59 km, the standard deviation is 1.9 km. The results show that the Moho depths in the study regions show the obvious regional tectonic features.
Gravity inversion can be used to determine Moho depths in sea regions where we lack adequate seismic information. In this study, the gravity anomaly is used to calculate the Moho depths of the South China Sea and adjacent regions. After isolating the gravity anomaly of Moho depths from the free-air gravity anomalies, the resulting gravity residual is used to invert the Moho depths based on Parker-Oldenburg inversion algorithm. To eliminate the high-frequency oscillations that occured in the inversion process, a cosine filter for gravity data filtering in wave number domain is applied, where smaller and greater frequency parameters are estimated from the energy spectrum of the residual gravity anomaly. The average difference in Moho depths between this study and the seismic measurement results is 1.59 km, the standard deviation is 1.9 km. The results show that the Moho depths in the study regions show the obvious regional tectonic features.
引文
[1] Hall R. Cenozoic Geological and Plate Tectonic Evolution of SE Asia and the SW Pacific: Computer-Based Reconstructions, Model and Animations[J]. Journal of Asian Earth Sciences, 2002, 20(4):353-431
[2] Taylor B, Hayes D E. Origin and History of the South China Sea Basin[A]//Hayes D E.The Tectonic and Geologic Evolution of Southeast Asian Seas and Islands:Part 2[M]. Washington D C:American Geophysical Union (Geophysical Monograph), 1983
[3] Ludwig W J. Kumar N, Houtz R E. Profiler-Sonobuoy Measurements in the South China Sea Basin[J]. Journal of Geophysical Research:Solid Earth, 1979, 84(B7): 3 505-3 518
[4] Nissen S S, Hayes D E, Buhl P, et al. Deep Penetration Seismic Soundings across the Northern Margin of the South China Sea[J]. Journal of Geophysical Research:Solid Earth, 1995, 100(B11): 22 407-22 433
[5] Yan P, Zhou D, Liu Z S. A Crustal Structure Profile Accross the Northern Continental Margin of the South China Sea[J].Tectonophysics, 2001,338(1): 1-21
[6] Hayes D E, Nissen S S. The South China Sea Margins: Implications for Rifting Contrasts[J]. Earth & Planetary Science Letters, 2005,237(3): 601-616
[7] Wu Z L, Li J B, Ruan A G, et al. Crustal Structure of the Northwestern Sub-Basin, South China Sea: Results from a Wide-Angle Seismic Experiment[J]. Science China Earth Sciences, 2012, 55(1):159-172
[8] Qiu X L, Ye S Y, Wu S M, et al. Crustal Structure across the Xisha Trough, Northwestern South China Sea[J]. Tectonophysics, 2001,341(1): 179-193
[9] Wang T K, Chen M K, Lee C S, et al. Seismic Imaging of the Transitional Crust across the Northeastern Margin of the South China Sea[J]. Tectonophysics, 2006, 412(3): 237-254
[10] 阮爱国, 牛雄伟, 丘学林,等, 穿越南沙礼乐滩的海底地震仪广角地震试验[J]. 地球物理学报, 2011, 54(12): 3 139-3 149 (Ruan Aiguo, Niu Xiongwei, Qiu Xuelin, et al. A Wide Angle Ocean Bottom Seismometer Profile across Liyue Bank, the Southern Margin of South China Sea[J]. Chinese Journal of Geophysics,2011, 54(12): 3 139-3 149)
[11] Braitenberg C, Wienecke S, Wang Y. Basement Structures from Satellite-Derived Gravity Field: South China Sea Ridge[J]. Journal of Geophysical Research: Solid Earth, 2006,111(B5)
[12] 秦静欣, 郝天珧, 徐亚, 等. 南海及邻区莫霍面深度分布特征及其与各构造单元的关系[J]. 地球物理学报, 2011, 54(12): 3 171-3 183 (Qin Jingxin, Hao Tiantao, Xu Ya, et al. The Distribution Characteristics and the Relationship between the Tectonic Units of the Moho Depth in South China Sea and Adjacent Areas[J]. Chinese Journal of Geophysics, 2011, 54(12):3 171-3 183)
[13] Pavlis N K, Holmes S A, Kenyou S C, et al. Correction to “The Development and Evaluation of the Earth Gravitational Model 2008 (EGM2008)”[J]. Journal of Geophysical Research:Solid Earth, 2013, 118(5):2 633
[14] Prasanna H M I, Chen W, íz H B. High Resolution Local Moho Determination Using Gravity Inversion: A Case Study in Sri Lanka[J]. Journal of Asian Earth Sciences, 2013, 74(18): 62-70
[15] Migliaccio F, Reguzzoni M, Sansò F, et al. GOCE Data Analysis: The Space-Wise Approach and the First Space-Wise Gravity Field Model[C]. The ESA Living Planet Symposium, Lacoste, 2010
[16] IOC, IHO, BODC. Centenary Edition of the GEBCO Digital Atlas[Z]. Livepool, UK,2003
[17] Whittaker J M, Goncharov A, Williams S E, et al.Global Sediment Thickness Data Set Updated for the Australian-Antarctic Southern Ocean[J]. Geochemistry Geophysics Geosystems, 2013, 14(8): 3 297-3 305
[18] Sawyer D S. Total Tectonic Subsidence: A Parameter for Distinguishing Crust Type at the US Atlantic Continental Margin[J]. Journal of Geophysical Research:Solid Earth, 1985, 90(B9): 7 751-7 769
[19] Barton P J. The Relationship between Seismic Velocity and Density in the Continental Crust——A Useful Constraint?[J] Geophysical Journal of the Royal Astronomical Society, 2010, 87(1): 195-208
[20] Parker R L. The Rapid Calculation of Potential Anomalies[J]. Geophysical Journal International, 1973, 31(4): 447-455
[21] Oldenburg D W. The Inversion and Interpretation of Gravity Anomalies[J]. Geophysics, 1974,39(4):526-536
[22] 刘光鼎. 中国海区及邻域地质地球物理系列图集[M]. 北京:科学出版社, 1992 (Liu Guangding. Geophysical Series Maps in China Sea and Adjacent Regions[M]. Beijing: Science Press, 1992)
[23] Bai Y L, Williams S E, Müller R D, et al. Mapping Crustal Thickness Using Marine Gravity Data: Methods and Uncertainties[J]. Geophysics, 2014, 79(2): 1-10
[24] 刘赛君, 曾钢平, 邱学林, 等. 海南岛西南海域地壳剖面海陆联合探测研究[J]. 地球物理学进展, 2011,26(3): 922-933 (Liu Saijun, Zeng Gangping, Qiu Xuelin, et al. The Crustal Profile and Onshore-Offshore Seismic Exploration in the Marine Area Southwest to Hainan Island[J]. Progress in Geophys, 2011, 26(3): 922-933)
[2] Taylor B, Hayes D E. Origin and History of the South China Sea Basin[A]//Hayes D E.The Tectonic and Geologic Evolution of Southeast Asian Seas and Islands:Part 2[M]. Washington D C:American Geophysical Union (Geophysical Monograph), 1983
[3] Ludwig W J. Kumar N, Houtz R E. Profiler-Sonobuoy Measurements in the South China Sea Basin[J]. Journal of Geophysical Research:Solid Earth, 1979, 84(B7): 3 505-3 518
[4] Nissen S S, Hayes D E, Buhl P, et al. Deep Penetration Seismic Soundings across the Northern Margin of the South China Sea[J]. Journal of Geophysical Research:Solid Earth, 1995, 100(B11): 22 407-22 433
[5] Yan P, Zhou D, Liu Z S. A Crustal Structure Profile Accross the Northern Continental Margin of the South China Sea[J].Tectonophysics, 2001,338(1): 1-21
[6] Hayes D E, Nissen S S. The South China Sea Margins: Implications for Rifting Contrasts[J]. Earth & Planetary Science Letters, 2005,237(3): 601-616
[7] Wu Z L, Li J B, Ruan A G, et al. Crustal Structure of the Northwestern Sub-Basin, South China Sea: Results from a Wide-Angle Seismic Experiment[J]. Science China Earth Sciences, 2012, 55(1):159-172
[8] Qiu X L, Ye S Y, Wu S M, et al. Crustal Structure across the Xisha Trough, Northwestern South China Sea[J]. Tectonophysics, 2001,341(1): 179-193
[9] Wang T K, Chen M K, Lee C S, et al. Seismic Imaging of the Transitional Crust across the Northeastern Margin of the South China Sea[J]. Tectonophysics, 2006, 412(3): 237-254
[10] 阮爱国, 牛雄伟, 丘学林,等, 穿越南沙礼乐滩的海底地震仪广角地震试验[J]. 地球物理学报, 2011, 54(12): 3 139-3 149 (Ruan Aiguo, Niu Xiongwei, Qiu Xuelin, et al. A Wide Angle Ocean Bottom Seismometer Profile across Liyue Bank, the Southern Margin of South China Sea[J]. Chinese Journal of Geophysics,2011, 54(12): 3 139-3 149)
[11] Braitenberg C, Wienecke S, Wang Y. Basement Structures from Satellite-Derived Gravity Field: South China Sea Ridge[J]. Journal of Geophysical Research: Solid Earth, 2006,111(B5)
[12] 秦静欣, 郝天珧, 徐亚, 等. 南海及邻区莫霍面深度分布特征及其与各构造单元的关系[J]. 地球物理学报, 2011, 54(12): 3 171-3 183 (Qin Jingxin, Hao Tiantao, Xu Ya, et al. The Distribution Characteristics and the Relationship between the Tectonic Units of the Moho Depth in South China Sea and Adjacent Areas[J]. Chinese Journal of Geophysics, 2011, 54(12):3 171-3 183)
[13] Pavlis N K, Holmes S A, Kenyou S C, et al. Correction to “The Development and Evaluation of the Earth Gravitational Model 2008 (EGM2008)”[J]. Journal of Geophysical Research:Solid Earth, 2013, 118(5):2 633
[14] Prasanna H M I, Chen W, íz H B. High Resolution Local Moho Determination Using Gravity Inversion: A Case Study in Sri Lanka[J]. Journal of Asian Earth Sciences, 2013, 74(18): 62-70
[15] Migliaccio F, Reguzzoni M, Sansò F, et al. GOCE Data Analysis: The Space-Wise Approach and the First Space-Wise Gravity Field Model[C]. The ESA Living Planet Symposium, Lacoste, 2010
[16] IOC, IHO, BODC. Centenary Edition of the GEBCO Digital Atlas[Z]. Livepool, UK,2003
[17] Whittaker J M, Goncharov A, Williams S E, et al.Global Sediment Thickness Data Set Updated for the Australian-Antarctic Southern Ocean[J]. Geochemistry Geophysics Geosystems, 2013, 14(8): 3 297-3 305
[18] Sawyer D S. Total Tectonic Subsidence: A Parameter for Distinguishing Crust Type at the US Atlantic Continental Margin[J]. Journal of Geophysical Research:Solid Earth, 1985, 90(B9): 7 751-7 769
[19] Barton P J. The Relationship between Seismic Velocity and Density in the Continental Crust——A Useful Constraint?[J] Geophysical Journal of the Royal Astronomical Society, 2010, 87(1): 195-208
[20] Parker R L. The Rapid Calculation of Potential Anomalies[J]. Geophysical Journal International, 1973, 31(4): 447-455
[21] Oldenburg D W. The Inversion and Interpretation of Gravity Anomalies[J]. Geophysics, 1974,39(4):526-536
[22] 刘光鼎. 中国海区及邻域地质地球物理系列图集[M]. 北京:科学出版社, 1992 (Liu Guangding. Geophysical Series Maps in China Sea and Adjacent Regions[M]. Beijing: Science Press, 1992)
[23] Bai Y L, Williams S E, Müller R D, et al. Mapping Crustal Thickness Using Marine Gravity Data: Methods and Uncertainties[J]. Geophysics, 2014, 79(2): 1-10
[24] 刘赛君, 曾钢平, 邱学林, 等. 海南岛西南海域地壳剖面海陆联合探测研究[J]. 地球物理学进展, 2011,26(3): 922-933 (Liu Saijun, Zeng Gangping, Qiu Xuelin, et al. The Crustal Profile and Onshore-Offshore Seismic Exploration in the Marine Area Southwest to Hainan Island[J]. Progress in Geophys, 2011, 26(3): 922-933)