Z-Terra’s CEO, Alexander Mihai Popovici, hosted a GSH Virtual Presentation on High Resolution, Wide Azimuth Tomography and Beam Tomography for Velocity Model Building on November 1, 2022. Click the link above to view the details on the GSH website. An excerpt is below:
The Z-Terra implementation of wide azimuth Beam Tomography is based on the Fast Beam Migration (FBM) algorithm. The Beam Tomography uses FBM to directly output a set of image points (x,y,z) with velocity update values, which bypasses the time consuming steps required for traditional tomography, including preparing the gathers for semblance analysis, semblance picking and back-projection picks QC. A 2000 sq km velocity model can be updated using 400 CPUs in less than 5 minutes. The Beam Tomography output contains image point azimuth information and this allows the tomographic update to go beyond the current limitation of limited wide azimuth velocity updates.
Beam Tomography allows for faster turnaround time for large 3-D seismic projects and at the same time increases the accuracy of the velocity model by using wide azimuth information that is typically unavailable in traditional tomography. Beam Tomography can be combined with Full Waveform Inversion (FWI) to speed up the convergence and obtain high resolution velocity models 10 to 100 times faster than the standard practice. While FWI is typically implemented in data space, FWI can also be implemented in image space, without the long offset and low frequency constraints of FWI in data space.