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"In this research the S speed structure is investigated by seismogram analysis of Washington's earthquake, C022801L using data of TUC station, Tucson, Arizona, U.S.A. The seismogram comparison between the observed and the synthetic seismogram is conducted in time domain and three components simultaneously. The initially input for the calculation of synthetic seismogram is earth model of PREMAN and CMT solution from the earthquake. A low-pass Butterworth filter with corner frequency of 20 mHz is convolved to observed and synthetic seismogram. Waveform comparison shows a real deviation when travel time and waveform of some wave phase are compared, namely on S wave, surface wave of Love and Rayleigh and wave ScS and ScS-2. This research shows, how sensitive the waveform is to the earth model, better than the method of travel time or the dispersion analysis. Research hereinafter is addressed to finish the found discrepancies at S wave, surface wave of Love and Rayleigh and ScS and ScS-2 wave, in observation station TUC. To obtain the seismogram fitting, correction for S speed structure in earth model is needed, that are changes of earth crust thickness, the speed model of  in upper mantle covering the speed gradient of h and value of zeroeth order coefficient for the h and v, for accomplishing the discrepancies at surface wave of Love and Rayleigh. Further correction on S speed is conducted to accomplish the deviation at S wave at earth layering systems from Upper Mantle up to a 630 km depth. Mean while for the ScS and ScS-2 wave phase the correction is carried out on S speed in the earth layers up to CMB. Fitting Seismogram is obtained at waveform of various wave phases that is S wave, surface wave of Love and Rayleigh and ScS, ScS-2 wave, either on travel time or especially also at oscillation number in Love wave. This result indicates that the anisotropy is occurred not only in upper mantle but till deeper earth layers, till CMB."

"ABSTRACTPenelitian untuk mengukur kedalaman Diskontinuitas Mohorovicic Moho dan zona subduksi antara Lempeng Indo-Australia yang menunjam Lempeng Eurasia telah dilakukan dengan menggunakan metode gravitasi dengan memanfaatkan data gravitasi citra satelit yang berasal dari satelit Geodetic Satellite GEOSAT dan European Remote-Sensing 1 ERS-1 . Kedua struktur ini terdapat kontras densitas sehingga penelitian dilakukan menggunakan metode gravitasi. Data satelit yang didapat berupa free air anomaly. Kemudian data dikoreksi bouguer dengan densitas rata-rata 2.64 g/cm2 dari metode parasnis sehingga didapatkan Complete Bouguer Anomaly SBA. Untuk mencari kedalaman Moho dan zona subduksi ditentukan dengan Energy Spectrum Analysis ndash; the Multi Window Test ESA-MWT dengan lintasan dari Selatan-Utara dan Timur-Barat. Dengan ESA-MWT, didapatkan 9 lapisan dan bisa mencapai kedalaman yang regional. Hasil kedalaman Moho bervariasi sebesar 28-63 km di lapisan ke-6. Juga dalam lintasan Timur-Barat, Moho didapatkan di lapisan ke-5 dengan kedalaman 34-49 km. Lempeng Indo-Australia berhasil ditemukan di kedalaman 54 km dan penunjaman dengan Lempeng Eurasia di kedalaman 106 km. Metode Multiscale Second Vertical Derivative MSSVD juga membantu mengonfirmasi keberadaan zona subduksi dengan adanya patahan reverse. Penelitian ini dikorelasikan dengan metode seismik.

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ABSTRACTStudy to measure depth of Mohorovicic Discontinuity and subduction zone of the Indo Australia Plate that subducted beneath Eurasia Plate has been done using gravity method with satellite gravity data comes from Geodetic Satellite GEOSAT and European Remote Sensing 1 ERS 1. These structures have contrast density, so that this study using gravity method. From satellite data obtained free air anomaly. The next step processing is Bouguer correction with average density 2.64 g cm3 comes from parasnis method dto obtain Simple Bouguer Anomaly SBA. The depth of Moho and subduction zone are determined from Energy Spectrum Analysis ndash the Multi Window Test ESA MWT with lines heading South North and East West. The result from ESA MWT shows that there are 9 layers and could reach regional depth, also the depth of Moho is about 28 63 km in 6th layer in South North lines, meanwhile in East West lines the depth of Moho is found in 34 49 km in 5th layer. Slab of Indo Australia is successfully found in the depth of 54 km, and the subduction zone found in 106 km. Multiscale Second Vertical Derivative MSSVD method is used to prove existence of subduction zone within fault reverse. This study is correlated with seismic method. "