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Geophysics/Seismic data processing


My questions are:

1. What is the difference between Automatic gain control and True amplitude recovery?
2. What does source and receiver statics mean?
3. Difference between repilca and parameter test?


Dear Shahbaz,

Here are my answers:

1- AGC is applied to compensate the amplitude decay with depth. It is like boosting up the amplitude based on a time gate. It is a sliding window operation with an average amplitude scaler. Normally it is done with a large window +100 or 200ms. On average, people choose 500ms time gate.

TAR is equivalent to AGC but involves a better approximation of velocity and absorption coeff. I cannot remember the function but I can tell you that its function is not as simple as AGC is.  

2- These are bulk shifts applied to the seismic traces. It is done to bring all information to a common datum because of topography and weathering layers. So, you need to shift the tracts according to the source and receiver's height above or below a regional datum on which the seismic data is being processed.

3- I'm not sure if you are confusing between a term vs. English. I cannot get this. I am sorry! Probably, someone else can answer to this after it is posted.  


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Farrukh Qayyum


I would like to answer Geophysical questions with keen interest, specifically exploration related. I want to hear from users for their queries on exploration geophysics/geology. Especially in the discipline of Reservoir Characterization from seismic reflection data. The questions related to basics and interpretational applications would be most welcome. I can also answer queries related to sequence and/or seismic stratigraphy, geology, general geomorphology, seismic geomorphology and other relevant questions. I can not answer the questions related to gravity, magnetic, or resistivity surveying or question related to the fluid dynamics. Such categories are not related to my experience.


Over eight years in different services with additional case studies of Pakistan, China, Saudi Arabia, North Sea, Africa and Netherlands offshore.

dGB Earth Sciences, The Netherlands.


4D Wheeler Diagrams: Concept and Applications, Qayyum, F., P. de Groot, N. Hemstra, and O. Catuneanu, 2014, Geological Society, London, Special Publications, v. 404, p. SP404.1, doi:10.1144/SP404.1.

A Modern Approach to Build 3D Sequence Stratigraphic Framework Qayyum, F., Hemstra, N., and Singh, R., 2013, Oil and Gas Journal, vol.111, issue 10.

Dense sets of seismic horizons - A New Approach to Stratigraphic Interpretation Qayyum, F., Hemstra, N., and de Groot, P., 2013, Geophysical Corner, AAPG Explorer, September Issue, 68-69.

Developments and Future Trends in Wheeler Diagrams Qayyum, F., Catuneanu, O., de Groot, P., 2013, 75th EAGE Conference & Exhibition incorporating SPE EUROPEC, London, UK, June 2013.

HorizonCube and Wheeler Transform Generated, Stratal Packages Identified and Correlated on 7 Regional 2D Seismic Lines McDonough, K.J., Qayyum, F., Bouanga, E., and Pierard, C., Horn, B., Gross, J., Danforth, A., Sterne, E.J., Granath, J., AAPG Annual Convention & Exhibition, May 2013

On the horizon, de Groot, P., Qayyum, F., Oilfield Technology, January 2013.

Attributes play important role in seismic interpretation, de Groot, P., Qayyum, F., Hart's E&P Magazine, p. 31-34, October 2012.

From 2D to 4D Wheeler Diagrams, F. Qayyum, P. de Groot, and N. Hemstra, William Smith Meeting 2012, London.

Building a Sequence Stratigraphic Framework from HorizonCube and Well Data F. Qayyum, P. de Groot, J. Yasin 74th EAGE Conference & Exhibition, 2012

An old favourite, F. Qayyum and P. de Groot, Oilfield Technology, March 2012.

Using 3D Wheeler diagrams in seismic interpretation the HorizonCube method F. Qayyum, P. de Groot,N. Hemstra First Break 30 (3), 103-109,2012

Master in Philosophy with specialization in reservoir characterization by using Sequence Stratigraphy. And master in Geophysics with a case study of Punjab Platform.

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Position Holder in Academics.

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