SIGMA-GEO offers a service for refining the velocity model of the upper part of the section to improve the quality of seismic data processing.

The relevance

Modern oil and gas seismic exploration, due to the peculiarities of the receive and source signal parameters, is not always able to restore reliable information about the velocity characteristics of the upper part of the section.
When interpreting seismic data in areas with difficult surface environment and a heterogeneous upper part of the section, it is necessary to take into account their influence.

Solutions

The proposed methodology for calculating velocity models, based on the use of shallow modification of the TEM (sTEM), makes it possible to reduce the uncertainties of the seismic depth-velocity model and, as a consequence, increase the accuracy of structural imaging, which was confirmed by the results of mathematical modeling (Shelokhov et al., 2018).
The method for calculating static corrections has been patented and tested at the largest fields in Eastern and Western Siberia.

The calculation graph includes several basic steps:

• interpretation of the sTEM data;
• calculation and calibration of coefficients of the Faust's equation;
• velocity inversion. 

Block diagram

Example of the result of using the approach

Problems to be solved

• Constructing a detailed geoelectric model of the upper part of the section;
• Ranking of the area according to the level of difficulty of the seismic geological conditions of the upper part of the section;
• Velocity inversion of the upper part of the section to a depth of 500 m in 2D and 3D versions.

SIGMA-GEO experience

• Employees' experience in this area exceeds 5 years; 
• The method for calculating static corrections has been patented and tested at the largest fields in Eastern and Western Siberia.

Geography of work