Converted wave prestack depth migration from topography: a comparison

Saúl Ernesto Guevara, Gary F. Margrave

Pre-stack depth migration is applied to synthetic PP and PS wave data, obtained over a geological model with structural features and topography. The geological model includes a dipping target, a reverse fault in the middle, and a hill on the surface. (See Figure below). No preprocessing or filtering was applied to the raw data. Two methods of migration, Kirchhoff and PSPI are applied and correct depths were obtained. However noticeable differences between each migration method can be observed, with some advantage for PSPI.

From a comparison between PP and PS depth migrated sections, the events are at the same depth, but the PS section looks a bit noisier and shows higher frequencies. The statics correction, applied as an alternative to migration from topography, shows detrimental effects in this migration. Future experiments can include amplitude analysis.