Mapping Land Subsidence in Bogotá, Colombia, Using the Interferometric Synthetic Aperture Radar (InSAR) Technique with TerraSAR–X Images   

Héctor MORA–PÁEZ, Fredy DÍAZ–MILA, and ​Leonardo CARDONA

https://doi.org/10.32685/pub.esp.38.2019.16

ISBN impreso obra completa: 978-958-52959-1-9

ISBN digital obra completa: 978-958-52959-6-4

ISBN impreso Vol. 4: 978-958-52959-5-7

ISBN digital Vol. 4: 978-958-52959-9-5​

Bogotá, the capital city of Colombia, is the largest and most populous urban center in the country. Established in a moderate seismic zone, its complex topography facilitates the occurrence of landslides and floods. The city has been subject to a massive migration process in recent years, which has generated the accelerated urbanization of the city and increased its vulnerability to various natural hazards. Bogotá is located within the Sabana de Bogotá, a tectonic–sedimentary basin consolidated after the uplifting of the northern Andes approximately 5 Ma. With TerraSAR–X radar images, a quantitative analysis of the subsidence in the Sabana de Bogotá was carried out using the interferometric synthetic aperture radar technique for the city of Bogotá. The obtained results allowed establishing subsidence values in the central region of the city on the order of 3.3 cm/y. It is important to note that the BOGT GPS Continuously Operating Reference Station, which is part of a global network, indicates a decreasing value in its vertical component on the order of 3.5 ± 0.09 cm/y.

Keywords: subsidence, Sabana de Bogotá, interferometric synthetic aperture radar.

Bogotá, la capital de Colombia, es el centro urbano más poblado y grande del país. Establecida en una zona sísmica moderada, su compleja topografía facilita la ocurrencia de deslizamientos e inundaciones. La ciudad ha sido objeto de un proceso de migración masiva en los últimos años, lo cual ha generado la urbanización acelerada de la ciudad y un incremento en la vulnerabilidad ante diversas amenazas naturales. Bogotá está localizada en la Sabana de Bogotá, una cuenca tectonosedimentaria consolidada después del levantamiento del norte de los Andes hace aproximadamente 5 Ma. Mediante el uso de imágenes de radar TerraSAR–X se realizó el análisis cuantitativo de la subsidencia en la Sabana de Bogotá empleando la técnica de interferometría de radar de apertura sintética para la ciudad de Bogotá. Los resultados obtenidos permitieron establecer valores de subsidencia en la región central de la ciudad del orden de 3,3 cm/año. Es importante señalar que la estación GPS permanente de referencia denominada BOGT, que forma parte de la red global, indica un valor de descenso en su componente vertical del orden de 3,5 ± 0,09 cm/año.

Palabras clave: subsidencia, Sabana de Bogotá, interferometría de radar de apertura sintética.

AIST                                                                                Advanced Information Systems Technology

ALOS–1, ALOS–2                                 Advanced Land Observing Satellite

CIC                                                                                   Cartographic Institute of Catalunya

cGPS                                                                             Continuous Global Positioning System

Cosmo–SkyMed                                    Constellation of Small Satellites for Mediterranean basin Observatory

DAMA                                                                         Departamento Administrativo del Medio Ambiente

DEM                                                                               Digital elevation model

DLR                                                                                  Deutsches Zentrum für Luft– und Raumfahrt (German Aerospace Center)

Envisat                                                                    ENVIronmental SATellite

ERS–1, ERS–2                                               European Remote Sensing Satellite

ESTO                                                                               Earth Science Technology Office

FHI                                                                                       Formal Housing Index

FOPAE                                                                           Fondo para la Prevención y Atención de Emergencias

GeoRED                                                                     Geodesia: Red de Estudios de Deformación

GIAnT                                                                             Generic InSAR Analysis Toolbox

GNSS                                                                               Global Navigation Satellite System

GPS                                                                                     Global Positioning System

IGAC                                                                                   Instituto Geográfico Agustín Codazzi

InSAR                                                                                Interferometric synthetic aperture radar

ISCE                                                                                     InSAR Scientific Computing Environment

JPL                                                                                         Jet Propulsion Laboratory

LOS                                                                                       Line–of–sight

MLE                                                                                       Maximum likelihood estimation

NASA                                                                                  National Aeronautics and Space Administration

NISAR                                                                                 NASA–ISRO SAR (NASA– Indian Space Research Organization synthetic aperture radar)

NSBAS                                                                               New Small Baseline Subset

RADARSAT–1, RADARSAT–2  Canada´s Earth observation satellite

SAR                                                                                           Synthetic Aperture Radar

SBAS                                                                                       Small baseline subset

SEGAL                                                                                   Space & Earth Geodetic Analysis Laboratory at the University of Beira Interior

SGC                                                                                           Servicio Geológico Colombiano 

SRTM                                                                                       Shuttle Radar Topography Mission

TerraSAR–X                                                                 German Earth–observation satellite

TDR                                                                                              Time domain reflectometry

UNESCO                                                                             United Nations Educational Scientific and Cultural Organization

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