Wavefront tomography

2D wavefront tomography and automatic picking of input data

Authors: Alxeander Bauer(modifications and extensions; original authors: Tilman Kluever and Eric Duveneck)

Version: July 2017

Description:

This package includes the 2D wavefront tomography and the automatic picker, which can be used to automatically pick data points for the wavefront tomography in the results of the 2D CRS stack.

The automatic picker has been extended from the original version by adding some constraints for coherence, minimum and maximum times, coordinates and attribute values. It works with GCC 6.2.

The code of the 2D wavefront tomography has been revised completely and some errors have been fixed. Also, it is now more easily to read and understand than the original code. The weights have been defined in a more intuitive fashion. The pdf-documentation of the old code is included in the folder Tomo/doc. However, parameter names introduced there are not valid anymore. Please refer to the self-documentation of the code (see below). The code works with GCC 6.2 and OpenMPI 2.0.

For the self-documentation of the codes, run the executables without parameters. Alternatively, type 'make tomodocu' or 'make pickdocu' in the example folder after compiling the codes.

A complete workflow starting from the 2D CRS attribute sections can be reproduced on a simple diffraction dataset in the example folder. All parameters are set in the makefile and plots can be done with provided shell-scripts.

References:

Bauer, A., Schwarz, B. and Gajewski, D. (2017): Utilizing diffractions in wavefront tomography. Geophysics, 82(2), R65–R73.
Duveneck, E. (2004): Velocity model estimation with data-derived wavefront attributes, Geophysics, 69, 265–274

2D estimation of wavefront attributes for passive seismic data

Authors: Leon Dieckmann

Version: July 2017

Download: 2D passive wavefront tomography

Description:

The archive contains two codes for the estimation of wavefront attributes for passive seismic data. It is similar to the common-reflection-surface approach, but handles the source excitation time as an additional parameter in the optimization process while the curvature of the normal wave vanishes. The two different implementations are comparable to the pragmatic approach and global optimization. The output file contains all wavefront attribute sections.

References:

Schwarz, B., Bauer, A. and Gajewski, D. (2016) Passive seismic source localization via common-reflection-surface attributes. Studia Geophysica et Geodaetica, 60(3), 531-546.