APPLICATION OF CONVERTED WAVE METHOD IN SYNTHETIC AND REAL DATA MODELS FOR IMAGING STUDY OF THIN BED LAYER

• Main Author: Nuraini, Isna
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/43995
• Institution: Institut Teknologi Bandung

One of the most important steps in the seismic method is data processing which aims to improve the quality of the signal to noise ratio seismic data, so as to produce a seismic section that represents the subsurface well. Seismic technology in hydrocarbon exploration still dominates today, especially the P-wave reflection seismic method. But in certain cases, the conventional P-P reflection seismic method has a weakness in giving an overview of complex geological conditions and often gives an ambiguous response. Therefore, we need another approach known as converted-wave seismic exploration using a multicomponent geophone that is able to record P waves on vertical components and S waves on horizontal components. As a validation step, the converted-wave method is applied to synthetic data with a thin bed layer model under shallow gas. The purpose of this study is to compare seismic section images of P-P and P-S processing that are affected by shallow gas against thin bed layers and the underlying geological structures. The results of the study show that the seismic section of the P-S processing migration is much better in describing the base of the shallow gas, so that the image of the thin bed layer under the shallow gas is seen more clearly than the P-P migration. This is confirmed by the vertical resolution calculation that has been done, when ???????? is smaller than ????????, it will increase the vertical resolution of the seismic data. Seismic data processing is continued by extracting information from the P-SV wave from the vertical component that associated with the P-P wave. This is based on the fact, that S waves are recorded on both the vertical and horizontal components of the geophone. The value of Vp/Vs during binning process have a role in the success of P-SV gather extraction on vertical components. When the CCP binning layout configuration model has a value of Vp / Vs ? 2, the extraction of P-SV waves on the vertical component is difficult. This is because the separation between CDP and CCP is quite close, so that the P-P wave energy is more dominant than the converted wave energy (P-SV).