Depth Conversion Methods

Instructor: Alan Atkinson
Date: Oct. 31 - Nov. 1, 2016
Duration: 2 days
Members (early bird/price): CAD $800/$1000 (plus GST)
Non-members (early bird/price): CAD $900/$1100 (plus GST)
Location: TBA
Time: 8:30 am to 4:30 pm


Attendees will gain most from the workshop if they are familiar with seismic interpretation and mapping.

Attendees are requested to bring laptops running Windows to undertake the computer based exercises. These will be performed in teams of two so not everyone is required to have one, but please let the organisers know if you will not be bringing your own. 

Course Description

Difficult depth conversion problems can be made simpler by breaking them down into smaller problems; velocity analysis techniques are worked through in exercises which reveal whether the overburden should treated as separate velocity layers, and highlight the degree of velocity variability within them. Optimal analysis of velocity data derived from sonic log and checkshots, seismic velocities and layer average interval velocities are covered in the practicals.

This analysis leads to an understanding of which velocity models are required to solve the depth conversion problem. Implementation of velocity models (including the ‘Vok’ method) using vertical profiles and maps to QC the process will be undertaken to gain experience of the techniques and to highlight their advantages and limitations.

Brief scene-setting lectures will introduce the exercises, and case studies will be interspersed through the workshop.


Alan Atkinson has over twenty five years of exploration, field development, and production geoscience experience with operators in West Africa, South Asia and the North Sea.

Specialising in the application of high end geophysics to structural and stratigraphic seismic interpretation, his areas of expertise are reservoir characterisation (using pre-stack inversion, AVO analysis) and velocity modelling (pre-stack depth migration and depth conversion).

He started his career working the North Sea with Phillips Petroleum and Amerada Hess in London, and subsequently moved to CNR International, working Angola and Côte d’Ivoire. He then moved to Cairn Energy, living and working in India, and becoming Chief Geophysicist during their successful Rajasthan campaign. Here, he supervised several significant seismic acquisition and processing programmes, and managed a geophysical studies team undertaking, amongst other projects, AVO modelling work and pioneering 4D studies on India’s largest onshore fields.

Alan now works as an independent consultant, based in Surrey, South East England, primarily advising on reserve evaluations for a variety of clients worldwide. He is an active member of SEG, EAGE, SPE and PESGB.