SURYA, TRISWAN MARDANI ADE (2017) APLIKASI METODE JOIN INVERSI SEISMIK GRAVITY UNTUK IMAGING DAN KOREKSI STATIK PADA DAERAH GEOLOGI KOMPLEKS. Undergraduate thesis, Institut Teknologi Sepuluh Nopember.
Preview |
Text
3712100003-Undergraduate_theses.pdf - Published Version Download (6MB) | Preview |
Abstract
Kondisi dekat permukaan kompleks terjadi ketika tubuh batuan beku atau karbonat terbawa dekat dengan permukaan. Keberadaan tubuh batuan tersebut dapat mengakibatkan perubahan kecepatan yang sangat signifikan. Permasalahan tersebut sangatlah sulit untuk diselesaikan dengan metode rekonstruksi kecepatan konvensional seperti tomografi waktu tempuh refraksi. Join inversi dari dua metode merupakan salah satu metode yang dapat digunakan untuk mendapatkan model kecepatan dekat permukaan. Pada penelitian ini digunakan metode join inversi travel time dan gravity untuk rekonstruksi model kecepatan dekat permukaan. Setelah itu dilakukan koreksi tomografi statik untuk mendapatkan posisi datum dan kecepatan lapisan lapuk. Penelitian ini menggunakan data sintetik gravitasi dan seismik. Data tersebut disintetik dengan metode talwani untuk data gravity dan elemen hingg untuk data seismik. Data seismik yang telah di forward kemudian dilakukan pemilihan first break untuk input tomografi travel time dan join inversi seismik gravity. Hasil dari metode join inversi seismik dan gravity memberikan model yang lebih baik daripada metode travel time tomografi. Perbedaan yang signifikan ialah adanya lapisan dengan kecepatan rendah yang terlihat pada model yang dihasilkan oleh metode join inversi dan tidak terlihat pada metode travel time tomografi. Selain koreksi statik dari model join inversi lebih baik dari segi kemenerusan dan kemiringan reflektornya.
=================================================================================================
Complex near surface condition occured when high velocity bodies were brought close to the surface. These bodies can be either high velocity carbonates or igneous rocks. The presence of the bodies can cause high contrast velocity change at near surface. This problem difficult to solve using conventional velocity reconstruction technique such as travel time tomography. Joint inversion of two geophysical data is one of many velocity reconstruction techniques. In this study, we used joint seismic travel time tomography and gravity data to get near surface velocity model. Then, we deployed static tomography based on joint seismic gravity inversion and travel time tomography in seismic reflection processing workflow.
We also used synthetic seismic and gravity data which resulted by forward modelling based on velocity model. Forward modelling of seismic data and gravity data is done by using finite difference method and Talwani method. To get the subsurface model, we use joint seismic gravity and first arrival refraction travel time tomography. The result of this study showed that joint seismic travel time and gravity is better than travel time tomography. The differences are shown in the shape of a high velocity body and appearance of a low velocity layer which isn’t shown in the travel time tomography velocity model. Based on the seismic section, Reflector dip dan continuity were result by static tomography using joint seismik gravity inversion was better than that of static using travel time tomography.
| Item Type: | Thesis (Undergraduate) |
|---|---|
| Uncontrolled Keywords: | Geologi kompleks, Travel time tomografi, Join Inversi, Koreksi Statik,Complex Geology, Travel Time Tomography, Joint Inversion, Static Correction |
| Subjects: | T Technology > TA Engineering (General). Civil engineering (General) > TA1637 Image processing--Digital techniques |
| Divisions: | Faculty of Civil Engineering and Planning > Geophysics Engineering > 33201-(S1) Undergraduate Thesis |
| Depositing User: | - TRISWAN MARDANI ADE SURYA |
| Date Deposited: | 25 Jan 2017 02:25 |
| Last Modified: | 06 Mar 2019 04:48 |
| URI: | http://repository.its.ac.id/id/eprint/3140 |
Actions (login required)
 |
View Item |