From vintage 2D to modern 3D seismic data: a case study from the Kazakh sector of the Caspian Basin

The North Caspian Fold and Thrust Belt of Kazakhstan lies between the Precaspian Basin to the north and the<br>Mangyshlak Palaeo-Trough to the south. The undeveloped Kultuk Field onshore is located along the frontal<br>zone of this folded belt, very close to the Caspian coastline. Poor to fair quality vintage 2D seismic (Fig. 1) and<br>various well data defined the traps for the Kultuk Field as low-amplitude structural closures within the Middle<br>Jurassic sequence. However, a newly acquired 225 km2 3D seismic data set provided not only a better<br>understanding of the trapping configuration within the known reservoir intervals, but it also imaged, for the first<br>time, the deeper structure beneath.