Multi-Sensor Geodetic Approach for Landslide Detection and Monitoring

Abstract

<p><strong>Abstract.</strong> The lesser Himalayan region is mostly affected by landslide events occurring due to rainfall, steep slopes and presence of tectonic activity beneath, causing loss of life and property. Some critical zones in the region have encountered recurring landslides over the past and need careful investigation for better planning and rescue operations. This research work presents a geodetic framework comprising multiple sensors to monitor the Sirobagarh landslide in Uttarakhand, India, which is affected by recurring landslides. Three field visits were made to this site for geodetic data collection using Terrestrial Laser Scanner (TLS), Global Navigation Satellite System (GNSS) and Robotic Total Station (RTS). Co-registration and vegetation removal of the TLS scans corresponding to the three visits resulted in generation of three Digital Elevation Models (DEM), which were differenced to estimate temporal movement of the landslide scarp. DEM differences indicate subsidence of the landslide scarp with vertical displacement values ranging from −0.05 to −5.0<span class="thinspace"></span>m. Rainfall induced debris flow is one of the prominent reason for large displacement magnitude (∼5<span class="thinspace"></span>m) in the upper landslide scarp. Horizontal displacement estimates obtained by geodetic network analysis of six GNSS stations installed on the study site show movement towards the Alaknanda river. The maximum horizontal and vertical displacement values for the GNSS stations were 0.1305<span class="thinspace"></span>m and −2.1315<span class="thinspace"></span>m respectively. Similar pattern is observed by displacement measurements of RTS target reflectors installed on a retaining wall constructed to arrest the debris flow approaorching the National Highway. The displacement estimates obtained from the sensors applied in this study indicate subsidence of the landslide scarp and surroundings. More time series observations can provide better understanding of the overall deformation process.</p>

Fusion of GNSS and Satellite Radar Interferometry: Determination of 3D Fine-Scale Map of Present-Day Surface Displacements in Italy as Expressions of Geodynamic Processes

“…GNSSs represent powerful instruments to realize global reference systems and to collect data for geodynamic interpretation. The DInSAR interferometric analysis represents a well-known and powerful technique used to detect and monitor surface motions of unstable areas at detailed scales such as those of unstable buildings [70][71][72] and landslides [4,6,13,15] as well as more widespread phenomena such as the subsidence and uplift zones [5,7,16,45].…”

Combining Sentinel-1 Interferometry and Ground-Based Geomatics Techniques for Monitoring Buildings Affected by Mass Movements

“…The capabilities of the two techniques complement each other in monitoring ground deformations. GNSS based analysis generally involves the establishment of a network of GNSS stations, data adjustment, transformation to a common datum, and differencing for displacement detection [35]. It is possible to obtain a three-dimensional (3D) point position with horizontal and vertical accuracy of 7-8 mm and 1-2 cm, respectively [36].…”

Functional Assessment and Implementation Studies on the 3D Printing Process in Structural Monitoring Applications

“…An important problem is an impact of external conditions on the measurement result-both atmospheric and weather, as well as other factors such as dust, vibration, or the presence of heat sources (machines and industrial installations). This is particularly important in geodetic deformation monitoring systems [3]-both industrial and natural facilities [4,5]. The need to ensure not only highly accurate but also reliable measurements performed by using total stations is particularly evident in the case of large areas subject to monitoring, e.g., in high mountains [6,7].…”

“…2022, 12, x FOR PEER REVIEW 2 of 13 installations). This is particularly important in geodetic deformation monitoring systems [3]-both industrial and natural facilities [4,5]. The need to ensure not only highly accurate but also reliable measurements performed by using total stations is particularly evident in the case of large areas subject to monitoring, e.g., in high mountains [6,7].…”