GNGTS 2018 - 37° Convegno Nazionale

576 GNGTS 2018 S essione 3.1 based method, a final model whose improved quality is assessed by a better horizontal alignment of the events in the CIGs. Acknowledgements. The seismic data processing is carried out using ProMAX of Halliburton/Landmark that is gratefully acknowledged. References Bozdag E., Trampert J., Tromp J.; 2011: Misfit functions for full waveform inversion based on instantaneous phase and envelope measurements . Geophysical Journal International. 185 , 2, 845-870. Fichtner A.; 2010: Full Seismic Waveform Modelling and Inversion . Berlin: Springer-Verlag. Galuzzi B., Zampieri E., Stucchi E.; 2017: A local adaptive method for the numerical approximation in seismic wave modelling . Communications in Applied and Industrial Mathematics, 8 , 1, 265-281. Galuzzi B., Tognarelli A., Stucchi E.M.; 2018: A Global-Local Experience of 2D Acoustic FWI on a Real Data Set . EAGE Technical Program Expanded Abstracts. doi: 10.3997/2214-4609.201800887 Mazzotti A., Bienati N., Stucchi E., Tognarelli A., Aleardi M., Sajeva A.; 2016: Two-grid genetic algorithm full waveform inversion . The Leading Edge, 35, 1068-1075. doi: 10.1190/tle35121068.1 Nocedal J., Wright S.; 2006: Numerical Optimization . Springer-Verlag. New York. Plessix R.; 2006: A review of the adjoint-state method for computing the gradient of a functional with geophysical applications . Geophysical Journal International, 167 , 495-503. doi: 10.1111/j.1365-246X.2006.02978.x Pratt, R. G.; 2008: Waveform tomography—successes, cautionary tales, and future directions . In 70 th EAGE Conference & Exhibition. doi: 10.3997/2214-4609.201405056 Scrocca D., Doglioni C., Innocenti F., Manetti P., Mazzotti A., Bertelli L., Burbi L., D’Offizi S.; 2003: CROPATLAS: seismic reflection profiles of the Italian crust. Mem. Descr. Carta Geol. It., 62 , 15-46. Tognarelli A., Stucchi E.M., Masumeci F., Mazzarini F., Sani F.; 2010: Reprocessing of the CROP M12A seismic line focused on shallow-depth geological structures in the northern Tyrrhenian Sea . Bollettino di Geofisica Teorica ed Applicata. 52 , 1, pp. 23-38. Virieux J., Operto S.; 2009: An overview of full waveform inversion in exploration geophysics . Geophysics, 74 , 6, WCC1-WCC26. Wolfe P.; 1969: Convergence Conditions for Ascent Methods . SIAM Review (Society for Industrial and Applied Mathematics), 11 , 2, 226-235. SEISMIC ATTRIBUTES IN THE INTERPRETATION OF CHANNEL GEOMETRIES: THE CASE STUDY OF THE CONGO BASIN C. Giorgetti 1 , A. Corrao 2 , M. Ercoli 1 , M. Porreca 1 , M.R. Barchi 1 1 Dipartimento di Fisica e Geologia, Università di Perugia, Italy 2 ENI spa Upstream & Technical services Introduction. Seismic attributes are commonly used in the oil & gas industry to improve the interpretability of seismic data (Taner et al. , 1979; Chopra and Marfurt, 2008). The application of this technique to enhance the presence of geological features like channelized systems and faults may be helpful to extrapolate additional information from data, therefore improving the seismic interpretation potential. It may also help to identify and optimize study’s techniques for further processes of seismic interpretation. We applied this technique to geological features of the lower Congo Basin. The geological framework of the area is the Angolan Passive Continental Margin. In this area the channelized systems of Zaire River and the wide fan of the Congo Basin develop with a length of about 800 km westward and a width of more than 400 km from Gabon to Angolan margins. The study region is characterised by turbidite systems within the Miocene deposits of the Malembo Formation, in a framework of extensional tectonics (Sikkema et al. , 2000; Savoye et al. , 2009). Throughout the application of attributes that enhances local signal variations, changes in amplitude, phase and frequency, it was possible to highlight acoustic impedance contrasts,