SE Solid Earth SE Solid Earth 1869-9529 Copernicus Publications Göttingen, Germany 10.5194/se-4-543-2013 Study on the limitations of travel-time inversion applied to sub-basalt imaging Flecha I. 1 Carbonell R. 1 W. Hobbs R. 2 Departament de Estructura i Dinàmica de la Terra, Institut de Ciències de la Terra Jaume Almera-ICTJA-CSIC, C/ Lluís Solé i Sabarís s/n, 08028, Barcelona, Spain Department of Earth Sciences, University of Durham, Durham DH1 3LE, UK 23 12 2013 4 2 543 554 Copyright: © 2013 I. Flecha et al. 2013 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://se.copernicus.org/articles/4/543/2013/se-4-543-2013.html The full text article is available as a PDF file from https://se.copernicus.org/articles/4/543/2013/se-4-543-2013.pdf

The difficulties of seismic imaging beneath high velocity structures are widely recognised. In this setting, theoretical analysis of synthetic wide-angle seismic reflection data indicates that velocity models are not well constrained. A two-dimensional velocity model was built to simulate a simplified structural geometry given by a basaltic wedge placed within a sedimentary sequence. This model reproduces the geological setting in areas of special interest for the oil industry as the Faroe-Shetland Basin. A wide-angle synthetic dataset was calculated on this model using an elastic finite difference scheme. This dataset provided travel times for tomographic inversions. Results show that the original model can not be completely resolved without considering additional information. The resolution of nonlinear inversions lacks a functional mathematical relationship, therefore, statistical approaches are required. Stochastic tests based on Metropolis techniques support the need of additional information to properly resolve sub-basalt structures.

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