Monitoring Surface Displacement of a Deep-Seated Landslide by a Low-Cost and near Real-Time GNSS System

Ela Šegina,Tilen Urbančič,Giulio Tagliaferro,Stefano Caldera,Eugenio Realini,Joaquín Reyes González,Tina Peternel,Matija Zupan,Angelo Consoli,Mateja Jemec Auflič,Andrea Gatti,Jernej Jež

doi:10.3390/rs12203375

Abstract

A prototype of a low-cost GNSS (Global Navigation Satellite System) monitoring system was installed on a deep-seated landslide in north-western Slovenia to test its performance under field conditions. The system consists of newly developed GNSS stations based on low-cost, dual-frequency receivers and open-source GNSS processing software. It automatically receives GNSS data and transmits them over the Internet. The system processes the data server-side and makes them available to the end user via a web portal. The detected surface displacements were evaluated through a comparison with the network of classic geodetic measurements. The results of a nine-month monitoring period using seven GNSS stations provided a detailed insight into the spatial and temporal pattern of deep-seated landslide surface movements. The displacement data were correlated with precipitation measurements at the site to reveal how different parts of the landslide react to rainfall. These data form the basis for the further development of an early-warning system which will help to manage the risk the landslide poses to the local population and infrastructure.

Highlights

Together with geotechnical, geological, and geomorphological investigations, the geodetic monitoring of surface movements forms an integral part of comprehensive landslide analyses for mitigation measurement planning [1,2,3,4,5,6]
The objective of this paper is to present the first results of the Global Navigation Satellite System (GNSS) low-cost monitoring system and to evaluate its performance under actual field conditions
As geodetic measurements were not carried out at the exact locations of the GNSS units, the measurements recorded at the geodetic point (i) located within the area of equivalent kinematic characteristics and (ii) closest to the individual GNSS unit, were considered

Summary

Introduction

Geological, and geomorphological investigations, the geodetic monitoring of surface movements forms an integral part of comprehensive landslide analyses for mitigation measurement planning [1,2,3,4,5,6]. The use of remote sensing data for landslide identification, detection, and monitoring has expanded significantly, mainly due to the increasing availability of very high-resolution data and improvements in computer processing. The advances in GNSS technology have allowed for the creation of new low-cost sensors which can provide continuous monitoring with medium to high precision, accuracy, and limited costs [9,10,11]. The efficiency of low-cost GNSS sensors in monitoring landslides has been confirmed by several authors [10,11,14,15,16]. The trend of using low-cost sensors for the continuous monitoring of landslides is increasing mainly due to their improved sensitivity and the wide range of their applicability [17,18,19,20]

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Conclusion