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Introduction

Seismic imaging is the numerical process of creating the subsurface image from reflections recorded on the surface. The process is essential for correcting the distortion effects caused by diffraction from geologic bed truncations and lateral movement of the energy between the reflection points on dipping beds and the surface locations. In this laboratory assignment, the students, majoring in exploration geophysics are required to use Tesseral Pro software for learning the seismic process such as forward modelling as well as imaging analysis. There are three modules, inclusive of building a subsurface model and creating a wave generator and modelling before carrying out pre-stack and post-stack migration on simple dipping model and salt dome model.

Forward modelling is the process of transforming a geological section (1D, 2D or 3D) into a synthetic seismic record by converting the depth and acoustic impedance of the section into travel time and seismic amplitude. This process is usually performed before and after the seismic survey in order to plan an acquisition program and make a correlation between the observed reflections and geologic interface. Besides that, the reverse process of forward modeling where the geological model is synthesized from the seismic data is known as inverse modelling. This process involves the transformation of seismic reflectivity into rock impedance such as acoustic and shear impedance.

As mentioned earlier, this laboratory assignment consists of three modules. Each of the module have different objectives which have been established in order to enhance the students’ understanding on synthetic seismic generation and migration analysis. The objectives of each module are as follows:


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