Reverse time migration

Abstract

Migration of stacked or zero-offset sections is based on deriving the wave amplitude in space from wave field observations at the surface. Conventionally this calculation has been carried out through a depth extrapolation. We examine the alternative of carrying out the migration through a reverse time extrapolation. This approach may offer improvements over existing migration methods, especially in cases of steeply dipping structures with strong velocity contrasts. This migration method is tested using appropriate synthetic data sets.

On long-time instabilities in staggered finite difference simulations of the seismic acoustic wave equations on discontinuous grids

“…In most modern seismic inversion approaches (cf. Baysal et al 1983;Tarantola 1984;Luo & Schuster 1991;Symes 2008;Virieux & Operto 2009), independent forward modeling jobs need to be performed for various source terms at each inversion step, which constitutes the most computationally intensive part of the entire inversion process.…”

An HDF5-based framework for the distribution and analysis of ultrasonic concrete data

“…The signal processing block consists of algorithms and programs to filter (i.e., reduce or remove noise and outliers) the sensed data and map those measurements to a reconstruction space that allows for the assessment and study of the probed specimen. The reconstruction techniques can range from simple A-scans visualizations (i.e., raw display of received timeseries reflection signals) and delay-and-sum approaches such as Synthetic Aperture Focusing Technique (SAFT) [1], to full wavefront modeling for 3D volume reconstruction such as Reverse Time Migration (RTM) [2]. The visualization block deals with the enhancement and post-processing of the reconstructed data in order to provide the most useful representation of the probed specimen.…”

An amplitude-preserved adaptive focused beam seismic migration method

“…On the other hand, oneway wave equation migration accuracy has also been improved significantly using different numerical algorithms, such as split-step Fourier, Fourier finite difference, and generalized screen propagator (Stoffa et al 1990;Ristow and Rühl 1994;Chen and Ma 2006;Li et al 2008;Kaplan et al 2010;Huang and Fehler 2000;Liu and Yin 2007;Zhu et al 2009;De Hoop et al 2000;Wu et al 2001;Le Rousseau and De Hoop 2003;Liu et al 2012). Reverse time migration based on two-way wave equations has become more and more practical in actual projects as computer technology develops (Baysal et al 1983), and many geophysicists have provided lots of constructive suggestions about the problems of time-consuming defects and low frequency imaging noise (Fletcher et al 2006;Symes 2007;Chattopadhyay and McMechan 2008;Abdelkhalek et al 2009;Li et al 2010).…”