Wide-azimuth, Broadband, and High-density 3D Seismic Survey in Eastern Edge of the Pre-Caspian Basin

The reef-flat facies reservoirs in carbonate are dominantly developed along the Eastern Edge of the Pre-Caspian Basin. Due to the influences of salt dome and strong heterogeneity, the pre-salt targets, stratigraphy-controlled traps, cannot be well imaged with conventional source, geometry, and processing methods. The narrow-azimuth and low-fold geometry cannot provide high S/N data and cannot image the salt-domes and the pre-salt reef-beach bodies distinctively; the lack of low frequencies and the loss of high frequencies severely affect the resolution of seismic data and inversion quality. The broadband vibrator which enhances low frequency from 1.5Hz has been developed and deployed in eastern edge of the Pre-Caspian basin, Kazakhstan in 2013. A Wide-azimuth, Broadband, and High-density (WBH) data volume was acquired. Following the acquisition, a WBH processing flow has been set up, the imaging accuracy of the salt dome boundaries and pre-salt reflections and resolution have been greatly improved. The geological problems of this block have been solved satisfyingly, and good results have been achieved.