Schlumberger

Technical Paper: Reverse Time Migration of Prism Waves for Salt Flank Delineation

Society: SEG
Paper Number: 414
Presentation Date: 2013
 

Abstract

In this paper, we present a new reverse time migration method for imaging salt flanks with prism wave reflections. It consists of four steps: (1) migrating the seismic data with conventional RTM to give the RTM image; (2) using the RTM image as a reflectivity model to simulate source-side reflections with the Born approximation; (3) zero-lag correlation of the source-side reflection wavefields and receiver-side wavefields to produce the prism wave migration image; and (4) repeating steps 2 and 3 for the receiver-side reflections. An advantage of this method is that there is no need to pick the horizontal reflectors prior to migration of the prism waves. It also separately images the vertical structures at a different step to reduce crosstalk interference. The disadvantage of prism wave migration algorithm is that its computational cost is twice that of conventional RTM. The empirical results with a salt model suggest that prism wave migration can be an effective method for salt flank delineation in the absence of diving waves.

Related services and products

 
Request More Information

Accurate Imaging in Complex Sub-Salt Areas

WesternGeco's Reverse Time Migration (RTM) accurately images steep dips in complex sub-salt areas as demonstrated on the BP 2004 velocity benchmark dataset.
Reverse-Time Migration (RTM) is an ultra high-end prestack two-way wave-equation migration.
Visit Reverse Time Migration page