3D FEM model of ground deformation in Deception Island (Antarctica)

• Main Author: Garrido Ballart, Sònia
• Other Authors: Universitat Politècnica de Catalunya. Departament de Matemàtica Aplicada III, Institut de Ciències de la Terra Jaume Almera, Zlotnik, Sergio, Geyer Traver, Adelina
• Format: Master Thesis
• Language: English
• Published: Universitat Politècnica de Catalunya 2017
• Subjects: Àrees temàtiques de la UPC::Enginyeria de la telecomunicació; Finite element method; Global Positioning System; 3D finite elements; forward finite elements; Deception Islad; ground deformation; GPS; Elements finits; Mètode dels; Sistema de posicionament global; Deception Island; South Shetland Islands; Antarc*; Antarctica
• Online Access: http://hdl.handle.net/2117/107661

Ground deformation has been demonstrated to be one of the most common signals of volcanic unrest. A variety of processes can cause ground deformation in active volcanic areas (e.g. magmatic processes, pore pressure variations in the hydrothermal systems, etc), and being able to recognize and distinguish them is crucial for evaluating the potential occurrence of future eruptions. Ground deformation can be measured using remote sensing or geodetic techniques like GPS or tiltmeters. However, even if geodetic monitoring networks may be capable of recording the ground deformation signal at surface, it is difficult to directly identify where and how are the pressure sources responsible for the observed deformation. Deception Island is the most active volcano in the South Shetland Islands, which last destructive events took place in 1967, 169 and 1970. Since the installation of the monitoring network in the island, it has experienced three uplift/downlift episodes, where ground deformation has been measured with GPS stations. . The objective of this work is to evaluate the location, shape, pressure source responsible for surface ground deformation recorded in Deception Island during the period 1995 - 2000 using Finite Elements (FE) linear elastic models. First, we have considered a 2D model where we have studied the effect of the different parameters in ground deformation. Second, 3D models simulating the real topography of Deception Island have been considered. The results of the 3D models are compared with the GPS data registered in some points of the island to approximate the shape, depth, excess pressure of the reservoir. Results obtained are crucial to understand the current magmatic situation of the island and the potential outcome of a future eruption.