GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 1.2 GNGTS 2024 Imaging the North-South deformaton through the applicaton of potental theory to InSAR measurements A. Barone 1 , P. Mastro 1 , A. Pepe 1 , M. Fedi 2 , P. Tizzani 1 , R. Castaldo 1 1 Isttuto per il Rilevamento Eletromagnetco dell’Ambiente (IREA), Consiglio Nazionale delle Ricerche (CNR), Napoli, Italia. 2 Dipartmento di Scienze della Terra, dell’Ambiente e delle Risorse (DiSTAR), Università degli Studi di Napoli Federico II, Napoli, Italia. Synthetc Aperture Radar Interferometry (InSAR) is a well-established technique for monitoring and modeling the ground deformaton feld in volcanic areas and geothermal felds. Specifcally, when SAR images are acquired along both the ascending and descending satellites orbits, the retrieval of the East-West (E-W) and vertcal components of the related three-dimensional (3D) ground deformaton feld is conceivable; the North-South (N-S) one is usually not available and diferent techniques have been proposed to solve this task. However, the resolutons and accuracies of these retrieved measurements are not always satsfactory. Here, we show a new approach for the retrieval of the N-S component and the reconstructon of the 3D ground deformaton feld in volcanic frameworks. The proposed methodology is based on the theory of the potental functons and the integral transforms of potental felds. We test our workfow on synthetc deformaton datasets computed according to the commonly used analytc volcanic deformaton sources (i.e., Mogi’s, Okada’s and Yang’s models). The results show that the proposed technique allows the retrieval of the N-S deformaton with negligible errors with respect to the expected one. We then consider this approach to reconstruct the 3D ground deformaton feld that occurred at Sierra Negra volcano (Galapagos Islands, Ecuador) during the 2017 – 2018.5 unrest, which has led to the erupton. The comparison with GNSS data shows that we are able to image the pre-eruptve N-S deformaton for this volcano with a mean error of about 5%, which is a surprising result for this kind of applicaton. The next step of this study is the modeling of the volcanic deformaton sources through the use of the retrieved 3D ground deformaton feld and showing the impact in the framework of the ambiguity solving. Corresponding author: barone.a@irea.cnr.it