Seismic Reprocessing as a Powerful Tool in Hydrocarbon Exploration

By

 Ahmed Abdou¹, Fekry Youssef¹, Magdy El Toukhy¹, Adel Antonuous²

(1) Khalda Petroleum Company, Cairo, Egypt (2) PGS Tensor, N/A,

 Old seismic data carry subsurface information more than what has been produced during the original processing. The most important objective of seismic data processing is to produce seismic sections that allow the interpreter to better define a prospect, while at the same time reflecting the subsurface geology. However, in order to achieve this objective, approximations of processing parameters took place to produce compromised data which can be used to interpret both shallow and deep horizons (reflectors). On the other hand, we would like to produce true and accurate geologic models in the three dimensions, but because of the complex nature of the subsurface and limitations of measuring techniques, we have to change from compromising processing into objective processing.

In many areas where the old seismic data represent the majority of the data set, seismic reprocessing becomes a very important and a relative cheap alternative to the acquisition of new seismic data.

Effective reprocessing of old seismic data are based on:

-         Specific objectives

-         Latest processing techniques

-         Minimizing approximations can significantly improve the final results which accurately depict the location and the real extent of hydrocarbon traps.

Applications of normal move out (NMO), reverse NMO, F-K filtering, surface consistent deconvolution, multiple attenuation processes and effective residual statics before and after stack have resulted in dramatic improvements of old seismic data and consequently enabled the interpreter in defining new prospects, which were not observed as a result of the original processing.

Khalda Petroleum Company has experienced data reprocessing in several areas which resulted in discovering hydrocarbons that added large amounts of reserves to the company.