Reverse Time Migration (RTM)Conventional wave equation migration is performed by propagating data downward through a velocity model into the earth and is limited where the structure and velocity field generate more complex arrivals, such as turning and 'prism' waves. Complex propagation paths give rise to arrivals that are seen as noise in the imaged data.
RTM propagates events both downward and upward through the earth model, explicitly handling turning waves and all other complex propagation paths. In many cases the ability to make use of these complex wave modes allows imaging of parts of the subsurface that otherwise have poor direct illumination.
|TTI RTM imaging of a line near the West Tonga discovery in the Gulf of Mexico featuring
coherent and focused subsalt images.
|A line near the Jack discovery in the Gulf of
Mexico, imaged using TTI RTM.