Application of persistent scatterers interferometry for surface displacements monitoring in N5E open pit iron mine using TerraSAR-X data, in Carajás Province, Amazon region

Aplicação de interferometria por espalhadores persistentes para monitoramento de deformações de superfície na mina de ferro a céu aberto N5E utilizando dados TerraSAR-X, na Província Carajás, região amazônica

ABSTRACT:

Carajás Mineral Province, Amazon region, is the most important one in Brazil. Vale S.A. Company has the right to operate in the area of the N5E mine. The work is conducted on rock alteration products of low geomechanical quality related to sandstones, siltstones, and a lateritic cover. In order to monitor ground deformation, 33 TerraSAR-X images covering the period of March 2012-April 2013 were used in the investigation. An interferometric synthetic aperture radar (InSAR) approach based on permanent scatterer interferometry (PSI) using an interferometric point target analysis algorithm was applied. Results demonstrated that most of the area was considered stable during the time span of the image acquisition. However, persistent scatterers (PSs) with high deformation rates were mapped over a landfill probably related to settlements. To validate the PSI data, graphs were generated with the displaced information based on topographic measurements in the field. The graphs showed that the surface deformations during TSX-1 runway coverage are within the miner’s safety threshold and do not present a risk of major problems. The PSI data provided a synoptic and detailed view of the deformation process that affects the mining complex without the need of field campaign or instrumentation.

KEYWORDS:
TerraSAR-X; interferometry; Amazon; deformation; radar