The S wave velocity structure of the earth below Eastern Southeast Asia has been investigated by analyzing the seismogram from surface wave to multiple depth waves in the time domain and three Cartesian components sim...The S wave velocity structure of the earth below Eastern Southeast Asia has been investigated by analyzing the seismogram from surface wave to multiple depth waves in the time domain and three Cartesian components simultaneously.The wave passes across the front area of subduction zone between the Philippine plate and the Asian plate.The main data are waveform comparisons,instead of the arrival times.The synthetic seismogram is calculated using the GEMINI method.The synthetic seismogram constructed by PREMAN global earth model deviates greatly from the measured one.To solve this problem,corrections are needed for the β speed structure.Corrections cover the gradient change of β_h,which turns from negative to positive in upper mantle layers as in the PREMAN,change of earth crust depth and change of zero order coefficients of β velocity function in all earth mantle layers.So,the fitting is obtained,as well as the arrival time or the waveform of Love and Rayleigh surface waves,the S wave and the repetitive depth waves ScS_2 and ScS_3.This result reveals that the Southeast Asia,being stretched due to tectonic release,has a mantle in some parts with negative anomaly of S wave velocity and vertical anisotropy in all earth mantle layers.展开更多
The S wave velocity structure between the hypocenter of C060394F earthquake,South Java and a series of observatory stations located in Australia and South-East Asia have been investigated through seismogram analysis i...The S wave velocity structure between the hypocenter of C060394F earthquake,South Java and a series of observatory stations located in Australia and South-East Asia have been investigated through seismogram analysis in the time domain and the three Cartesian components.The synthetic seismogram is constructed from the PREMAN global earth model.Seismogram comparison between the measured and synthetic seismograms shows large discrepancies.A correction to the S wave velocity structure is needed to solve these discrepancies.Seismogram analysis and fitting at the observatory stations located in Australia show a positive anomaly,whereas the stations in South-East Asia show a strong negative anomaly.Vertical anisotropy occurred in the upper mantle layer and earth mantle layers beneath it.The seismogram analysis in the time domain and the three components simultaneously provides a better picture of the earth model,compared to the analysis of the seismogram with arrival time,travel time difference and dispersion analysis.展开更多
基金This research is funded by the DanaHibah Penelitian Dasar of DIKTI (Grant Fund of the Basic Research from Higher Education Agency) with grant number 019/SP3/PP/DP2M/Ⅱ/2006
文摘The S wave velocity structure of the earth below Eastern Southeast Asia has been investigated by analyzing the seismogram from surface wave to multiple depth waves in the time domain and three Cartesian components simultaneously.The wave passes across the front area of subduction zone between the Philippine plate and the Asian plate.The main data are waveform comparisons,instead of the arrival times.The synthetic seismogram is calculated using the GEMINI method.The synthetic seismogram constructed by PREMAN global earth model deviates greatly from the measured one.To solve this problem,corrections are needed for the β speed structure.Corrections cover the gradient change of β_h,which turns from negative to positive in upper mantle layers as in the PREMAN,change of earth crust depth and change of zero order coefficients of β velocity function in all earth mantle layers.So,the fitting is obtained,as well as the arrival time or the waveform of Love and Rayleigh surface waves,the S wave and the repetitive depth waves ScS_2 and ScS_3.This result reveals that the Southeast Asia,being stretched due to tectonic release,has a mantle in some parts with negative anomaly of S wave velocity and vertical anisotropy in all earth mantle layers.
文摘The S wave velocity structure between the hypocenter of C060394F earthquake,South Java and a series of observatory stations located in Australia and South-East Asia have been investigated through seismogram analysis in the time domain and the three Cartesian components.The synthetic seismogram is constructed from the PREMAN global earth model.Seismogram comparison between the measured and synthetic seismograms shows large discrepancies.A correction to the S wave velocity structure is needed to solve these discrepancies.Seismogram analysis and fitting at the observatory stations located in Australia show a positive anomaly,whereas the stations in South-East Asia show a strong negative anomaly.Vertical anisotropy occurred in the upper mantle layer and earth mantle layers beneath it.The seismogram analysis in the time domain and the three components simultaneously provides a better picture of the earth model,compared to the analysis of the seismogram with arrival time,travel time difference and dispersion analysis.
