Ray-based reflection tomography has become widely used as a tool for updating velocity models in depth imaging. Historically, development of ray-based tomography for depth imaging followed two separate methodologies. Early ray-based tomography was based on differences in traveltime observed between modeled data and actual seismic data (Bishop et al, 1983). As technology for imaging in complex a...

In general, Green’s functions obtained with seismic interferometry are only estimates of the true Green’s function, introducing uncertainties to the information recovered from them. However, there are still many cases in which the sourcereceiver geometries are suitable for seismic interferometry, usually allowing the recovery of kinematic information. Here we show how to use the singular value ...

Gaussian beams are a well-known high-frequency wavefield approximation. A more accurate representation can be obtained by the complex eikonal equation. We propose a constructive algorithm for solving the complex eikonal equation. By re-writing the complex traveltime as background real and imaginary parts and their respective perturbations, we arrive at an update scheme that aims at solving the ...

The point-source traveltime field has an upwind singularity at the source point. Consequently, all formally high-order, finite-difference eikonal solvers exhibit firstorder convergence and relatively large errors. Adaptive upwind finite-difference methods based on high-order Weighted Essentially NonOscillatory (WENO) RungeKutta difference schemes for the paraxial eikonal equation overcome this ...

In this paper, we demonstrate that better primary preservation and effective surface multiple attenuation can be achieved by applying various iterative surface multiple attenuation approaches in different domains and in different areas. In areas where smaller moveout separation between primary and multiple exist, a conservative least-squares adaptive subtraction method is used to preserve prima...

Estimating an accurate velocity function is one of the most critical steps in building an accurate seismic depth image of the subsurface. In areas with significant structural complexity, one-dimensional updating schemes become unstable, and more robust algorithms are needed. Reflection tomography both in the premigrated (Bishop et al., 1985) and postmigrated domains (Stork, 1992; Kosloff et al....

This paper revisits the problem of recovering a smooth, isotropic, layered wave speed profile from surface traveltime information. While it is classic knowledge that the diving (refracted) rays classically determine the wave speed in a weakly well-posed fashion via the Abel transform, we show in this paper that traveltimes of reflected rays do not contain enough information to recover the mediu...

{ Methods are developed for design of linear tomographic reconstruction algorithms with speciied properties. Assuming a starting model with constant slowness, an algorithm with the following properties is found: (1) The optimum constant for the starting model is determined automatically. (2) The weighted least-squares error between the predicted and measured traveltime data is as small as possi...