Geophysics
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| This is my past life, so all this work is now dated. It covers mostly image processing and inversion |
Image Processing
Multiscale analysis of geophysical images
We developed a mathematical framework which allows for the analysis, processing and inversion of gravity and magnetic images, based on multiscale edges. These edges represent the main features in an image, and they are a significant aid in the visual analysis and interpretation of potential field images. Also, under restrictive but geologically reasonable assumptions, these edges have simple spatial relationships with the location of contacts between bodies of different density and/or susceptibility and can consequently be used in an inverse process to reconstruct approximate 3-D models of the underground geology
- Boschetti F., 2005, Improved edge detection and noise removal in gravity maps via the use of gravity gradients, Journal of Applied Geophysics, Volume 57, Issue 3 , April 2005, Pages 213-225.
- Boschetti F., P. Hornby and F.G. Horowitz, 2001, Wavelet based inversion of gravity data, Exploration Geophysics, 32, 48-55.
- D. Holden, N. Archibald, F. Boschetti, M. Jessell, 2001, "Inferring Geological Structures Using Wavelet-Based Multiscale Edge Analysis and Forward Models", Exploration Geophysics.
- Hornby, P., Boschetti F., and F.G. Horowitz, "Analysis of Potential Field Data in the Wavelet Domain", Geophysical Journal International, 137, 175-196, 1999
- Archibald, N.J., P. Gow, and F. Boschetti, Multiscale edge analysis of potential field data, 1998, Exploration Geophysics., 30, 38-44.
Feature removal and improved downward continuation of potential field maps
Building on the theory developed in the multiscale analysis of geophysical images, we are able to isolate or remove individual anomalies from potential field maps. Depending on the purpose of the processing, we can either leave adjacent anomalies untouched, or account for the effects of the removed anomaly. Also, by constraining the process with the information contained in the multiscale edges, improvement in the sharpening inherent in the downward continuation of potential field maps can be achieved, thereby considerably improving the visual inspection of gravity and magnetic signals
- Boschetti, F., Therond, V., and Hornby, P., 2005, Feature removal and isolation in potential field data, Geophysical Journal International, Volume 159 Issue 3 Page 833.
- Trompat H., Boschetti F., and Hornby P., 'Improved downward continuation of potential field data', Exploration Geophysics, 2003, v34#4, pp249-256.
- Boschetti F., 2005, Improved edge detection and noise removal in gravity maps via the use of gravity gradients, Journal of Applied Geophysics, Volume 57, Issue 3 , April 2005, Pages 213-225.
Measure of image similarity
In a step towards the development of a tool for applications such as numerical inversion, geological image retrieval, geological feature extraction and image data set browsing, we propose a set of criteria which are based upon spatial relations between geological structures, in order to develop a measure of similarity between geological sections. By giving different weights to the criteria, the technique can be tuned to different geological problems. The weights are determined automatically when a user ranks sets of test images, without the need to assign numerical 'a priori' values
- Kaltwasser P., Boschetti F., and Hornby P., 2004, Measure of similarity between geological sections accounting for subjective criteria, Computer & Geosciences, Vol 31/1 pp 29-34 .
Other Geophysical Signal processing
- Boschetti F., M. Dentith, R. List, A fractal based algorithm for detecting first arrivals on seismic traces, 1996, Geophysics, 61, 1095-1102.(see my thesis)
- Ord A., Boschetti F, and Hobbs B., 2004, "3D Imaging of Jointed Rock Masses", in Fractals in Geotechnical Engineering, D. Kolymbas (editor), Logos, Berlin
- Galybin K, Boschetti F & Dentith M, 2006, "A new approach to potential field data collection" , Journal of Geodynamics, 43, Issue 2, March 2007, Pages 248-261 .
- Durrleman, S., Boschetti F, A. Ord, and K. Regenauer-Lieb (2006), "Automatic detection of particle aggregation in particle code simulations of rock deformation", Geochem. Geophys. Geosyst., 7, Q05006, doi:10.1029/2005GC001063.
- Strykowski G., Boschetti F., and Papp G. 2004, "Estimation of the mass density contrasts and the 3D geometrical shape of the source bodies in the Yilgarn area, Eastern Goldfields, Western Australia", Journal of Geodynamics
Inversion of geophysical data
- Boschetti F., M. Dentith, R. List, Inversion of seismic refraction data using Genetic Algorithms, 1996, Geophysics, 1715-1727.(see my thesis)
- Boschetti F., M. Dentith, R. List, Inversion of gravity and magnetic data by Genetic Algorithm, 1997, Geophysical Prospecting, 461-478 (see my thesis).
- Boschetti F. and L. Moresi, 2001, "Interactive Inversion in Geosciences", Geophysics, 64, 1226-1235.