Time processing

A single project may include data from several seismic surveys obtained in different surface seismo-geological conditions using different techniques, equipment and field observation parameters. Correct merging and regularization of heterogeneous source seismic data is a key factor determining the efficiency of all subsequent processing procedures. PetroTrace has many years of experience in balancing, matching and regularizing 2D/3D/4D survey data obtained with different observation parameters and performed during different field seasons.

Restoration of true reflection amplitude ratios and wide range of the recording amplitude-frequency spectrum is one of the critical conditions for a reliable dynamic interpretation. To effectively extract the useful signal, PetroTrace uses flexible adaptive noise reduction techniques to eliminate the noise component without distorting the amplitudes of the reflected waves. Robust deconvolution, Q-compensation and Deghosing and other procedures are used to extend the spectrum of the seismic recording both towards high and low frequencies and stabilize the pulse shape. Our proprietary quality control tools allow continuous auditing of the entire processing in order to select optimal procedure parameters and obtain seismic images with maximum time and spatial resolution at high signal-to-noise ratios.

Significant differences in the heights of excitation and reception points, as well as velocity anomalies in the upper part of the media can significantly distort the seismic image of the environment. The PetroTrace team has a full set of tools for correcting static corrections of different magnitudes and frequencies, both by reflected and refracted waves. We use advanced commercial software and proprietary methods to correct statics for topography and model anomalies associated with permafrost zones, buried beds, basalt indusions and sand dunes. The proprietary iNSTA-GEO® seismic data processing system and methodology for interactive static corrections in areas characterized by complex structure of the near-surface sections allow us to restore the true position of reflecting horizons.

Multiple reflections, or the energy of waves reflected from more than one boundary, introduce a high degree of uncertainty in the structural interpretation and prediction of reservoir properties from seismic data. The presence of multiple waves makes it difficult to identify reflections from target horizons and does not allow performing a detailed correlation of structural and stratigraphic elements in the study interval. PetroTrace processors use the most innovative methods to suppress multiple waves of various nature, both before and after migration, including procedures such as Radon transform, SRME, WEMA, DEGHOSTING and another advanced techniques.

Data obtained using high-density, high-density observing systems have higher vertical and horizontal resolution compared to data obtained using conventional field methods. Increasing the resolution of the seismic record leads to significant improvements in the accuracy of structural constructions and predictions of reservoir properties. At the same time, the amount of raw seismic information obtained with high-density observation systems requires significant computing power and data storage systems. PetroTrace has both the necessary experience and powerful resources to process and analyze the data.

Marine seismic data processing differs from land seismic data processing and has its own specifics. The PetroTrace team has extensive experience in processing 2D/3D marine seismic data from different regions, obtained both in shallow and deep water. Among the company's successfully completed projects, there are extremely complex projects, such as projects located in land-to-sea transition zones. These projects require the most modern and flexible tools and nonstandard solutions, like adapting typical land seismic data processing workflows to the needs of marine data. The company's considerable experience in marine data processing also includes processing of data obtained by various acquisition methods (streamer cable and OBC/OBN receivers) combined into a single seismic data cube.

4D seismic is an effective method of field development monitoring. The 4D technology is based on a comparative analysis of kinematic and dynamic characteristics of 3D data of at least two 3D surveys acquired in different years in the area of the field development. The data is processed using a unified workflow. Subsequent interpretation allows to evaluate the impact of field development, localize zones of boundary water and/or bottom water leakage, detect pressure drop areas, as well as areas unaffected by development. The number of active 4D processing projects in the world is not very high, and accordingly, the number of companies with 4D processing experience is also limited. PetroTrace has qualified personnel who are able to perform 4D processing and interpretation at a high level.

Vertical seismic profiling (VSP) is performed to build a detailed velocity model, accurately tie reflections registered at the surface to the lithological section and study near-wellbore space using P-wave and shear-wave images of the medium. VSP results allow to increase reliability and accuracy of processing and interpretation of 2D and 3D seismic data. PetroTrace specialists have experience in processing well seismic data obtained with different field acquisition techniques: standard like 1D (zero offset) VSP, Оffset VSP and non-standard like Walkaway VSP, 3D VSP, Vertical Incidence VSP, fiber optic acquisition DAS and others. The applied technologies and processing sequence, which includes a whole complex of necessary procedures, allow to solve kinematic and dynamic problems of any VSP acquisition technique. PetroTrace specialists can participate in planning of the acquisition system, perform data processing and interpretation, and conduct expert evaluation of completed VSP projects.