Basic Depth Imaging Workflow

Audience

Geophysicist requiring entry level knowledge on the depth imaging methodology.

Content

This course begins with an important question – Why do we migrate. The theoretical fundamentals of imaging are reviewed with the emphasis placed on a practical understanding of migration. A comparison between Pre-Stack Time Migration (PSTM) and Pre-Stack Depth Migration (PSDM) is made and their main differences are discussed. Participants work through the workflow to process a dataset through a depth imaging sequence and learn how to build, modify and quality control (QC) velocity models, run and QC tomographic updates of these models and run Kirchhoff pre-stack migrations. The program is designed for a marine dataset but can be tailored to a land dataset on request.

The main topics covered include:

• Reflection, transmission and refraction and introduction to PSDM.
• Geometry definition and setting up the velocity zone
• Water bottom horizon picking on PSDM data using an interpretation toolbox
• Building an initial velocity model using well data
• Travel times computation and Kirchhoff migration
• Time to depth conversion
• Anisotropy concepts review
• Well calibration and delta computation
• VTI anisotropic model building and Kirchhoff migration
• Automatic RMO picking on CIG and quality factor
• Multi-layer non-linear tomographic inversion, the sediment velocity model update and QC
• STI PSDM

Learning Objectives

• List the different steps of depth imaging processing
• List the main elements needed to build a velocity depth model
• Build an initial velocity model using well data and an interpretation workstation
• Understand the key components of the tomographic inversion sequence
• Competently explain the anisotropy concept
• Capable of generating and updating an anisotropic model using tomographic sequence
• Be able to carry out a STI PSDM

Duration

5 days

Number of Participants

20

Prerequisites

Trainees should have background in time processing, and be familiar with the software used

Software Used

Geovation

Course Format

Classroom presentations and exercises

Find Out More

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Our proprietary courses are fully customizable and can be offered at a time and location convenient to you. Please request a course for more information.