3D Pre-Stack Plane Wave Full Waveform Inversion

PSDM has been in place for decades with numerous tools to derive velocity fields in depth,<br>particularly in mature areas such as the Gulf of Mexico. The existing methods have reached<br>their limits to further define and/or fine-tune the velocity models. With the new wide azimuth<br>acquisitions where better illumination is foreseeable, velocities can be more accurately<br>determined. One of the most advanced tools is to use full waveform inversion. Pre-stack<br>seismic full waveform inversion is a highly challenging task due to non-linearity and nonuniqueness.<br>Combined with compute intensive forward modeling and residual wavefield back<br>propagation, the method makes the technique computer intensive, especially for 3D projects.<br>For PSDM, forward modeling and reverse time migration are widely used in the industry.<br>Even in the 3D sense the focus has become what sort of methods could be used to achieve<br>higher resolution velocity models. The answer is full waveform inversion. Here we examine<br>the time domain plane wave implementation of 3D waveform inversion supported with<br>synthetic and field data examples.