A Ground Surface Deformation Monitoring InSAR Method Using Improved Distributed Scatterers Phase Estimation

In recent years, distributed fiber optic strain sensing (DFOSS) technology has demonstrated a solution for continuous deformation monitoring from subsurface to surface along the wellbore. In this study, we installed a single-mode optical fiber cable in a shallow trench to establish an effective technique for ground surface deformation mapping. We conducted three experimental field tests (iron plate load, water tank filling up load, and airbag inflation) in order to confirm the strain sensitivity of DFOSS for static loads, dynamic overload, excavation, subsidence, and uplift. This paper also presents two installation methods to couple the fiber cable with the ground under various environmental conditions; here, the fiber cable was installed in a shallow trench with one part buried in the soil and another part covered with cement. Our results suggest that covering the cable with cement is a practical approach for installing a fiber cable for ground surface deformation monitoring. By combining this approach with wellbore DFOSS, accurate surface–subsurface deformation measurements can be obtained for three-dimensional geomechanical monitoring of CO2 storage and oil and gas fields in the future.

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Imaging ground surface deformations in post-disaster settings via small UAVs

Geoscience Letters ◽

10.1186/s40562-021-00194-8 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Richard L. Ybañez ◽

Audrei Anne B. Ybañez ◽

Alfredo Mahar Francisco A. Lagmay ◽

Mario A. Aurelio

Keyword(s):

Surface Deformation ◽

Ground Surface ◽

Point Clouds ◽

Lateral Spreading ◽

Fault Movement ◽

Field Surveys ◽

3D Point Clouds ◽

Vertical Displacements ◽

Resolution Imaging ◽

Post Disaster

AbstractSmall unmanned aerial vehicles have been seeing increased deployment in field surveys in recent years. Their portability, maneuverability, and high-resolution imaging are useful in mapping surface features that satellite- and plane-mounted imaging systems could not access. In this study, we develop and apply a workplan for implementing UAV surveys in post-disaster settings to optimize the flights for the needs of the scientific team and first responders. Three disasters caused by geophysical hazards and their associated surface deformation impacts were studied implementing this workplan and was optimized based on the target features and environmental conditions. An earthquake that caused lateral spreading and damaged houses and roads near riverine areas were observed in drone images to have lengths of up to 40 m and vertical displacements of 60 cm. Drone surveys captured 2D aerial raster images and 3D point clouds leading to the preservation of these features in soft-sedimentary ground which were found to be tilled over after only 3 months. The point cloud provided a stored 3D environment where further analysis of the mechanisms leading to these fissures is possible. In another earthquake-devastated locale, areas hypothesized to contain the suspected source fault zone necessitated low-altitude UAV imaging below the treeline capturing Riedel shears with centimetric accuracy that supported the existence of extensional surface deformation due to fault movement. In the aftermath of a phreatomagmatic eruption and the formation of sub-metric fissures in nearby towns, high-altitude flights allowed for the identification of the location and dominant NE–SW trend of these fissures suggesting horst-and-graben structures. The workplan implemented and refined during these deployments will prove useful in surveying other post-disaster settings around the world, optimizing data collection while minimizing risk to the drone and the drone operators.

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3D Visual Technology of Geo-Deformation Disasters Induced by Mining Subsidence Based on ArcGIS Engine

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.500.428 ◽

2012 ◽

Vol 500 ◽

pp. 428-436 ◽

Cited By ~ 2

Author(s):

Ke Ming Yang ◽

Jun Ting Ma ◽

Bo Pang ◽

Yi Bin Wang ◽

Ran Wang ◽

...

Keyword(s):

Coal Mining ◽

Surface Deformation ◽

Ground Deformation ◽

Ground Surface ◽

Horizontal Displacement ◽

Mining Subsidence ◽

Underground Coal Mining ◽

Vertical Movements ◽

Probability Integral Method ◽

Arcgis Engine

Mining subsidence often produces significant horizontal and vertical movements at the ground surface, the surface deformation induced by underground coal mining can be predicted by probability integral method, and the surface geo-deformation disasters can be visualized based on GIS components. A three dimensional (3D) visualizing system of surface geo-deformation information is designed and developed with ArcGIS Engine and C# in the study. According to the surface deformation-predicted data induced by underground coal mining in Guobei Coalmine of Huaibei mine field, the extents and degrees of ground deformation disasters are visualized in 3D views for surface vertical subsidence, slope, curvature, horizontal displacement and horizontal strain based on the GIS-developed application platform.

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Copernicus Sentinel-1 MT-InSAR, GNSS and Seismic Monitoring of Deformation Patterns and Trends at the Methana Volcano, Greece

Applied Sciences ◽

10.3390/app10186445 ◽

2020 ◽

Vol 10 (18) ◽

pp. 6445 ◽

Cited By ~ 1

Author(s):

Theodoros Gatsios ◽

Francesca Cigna ◽

Deodato Tapete ◽

Vassilis Sakkas ◽

Kyriaki Pavlou ◽

...

Keyword(s):

Land Surface ◽

Surface Deformation ◽

Ground Deformation ◽

Local Population ◽

Seasonal Fluctuation ◽

Satellite System ◽

Deformation Monitoring ◽

Persistent Scatterers ◽

Geothermal Activity ◽

Global Navigation Satellite

The Methana volcano in Greece belongs to the western part of the Hellenic Volcanic Arc, where the African and Eurasian tectonic plates converge at a rate of approximately 3 cm/year. While volcanic hazard in Methana is considered low, the neotectonic basin constituting the Saronic Gulf area is seismically active and there is evidence of local geothermal activity. Monitoring is therefore crucial to characterize any activity at the volcano that could impact the local population. This study aims to detect surface deformation in the whole Methana peninsula based on a long stack of 99 Sentinel-1 C-band Synthetic Aperture Radar (SAR) images in interferometric wide swath mode acquired in March 2015–August 2019. A Multi-Temporal Interferometric SAR (MT-InSAR) processing approach is exploited using the Interferometric Point Target Analysis (IPTA) method, involving the extraction of a network of targets including both Persistent Scatterers (PS) and Distributed Scatterers (DS) to augment the monitoring capability across the varied land cover of the peninsula. Satellite geodetic data from 2006–2019 Global Positioning System (GPS) benchmark surveying are used to calibrate and validate the MT-InSAR results. Deformation monitoring records from permanent Global Navigation Satellite System (GNSS) stations, two of which were installed within the peninsula in 2004 (METH) and 2019 (MTNA), are also exploited for interpretation of the regional deformation scenario. Geological, topographic, and 2006–2019 seismological data enable better understanding of the ground deformation observed. Line-of-sight displacement velocities of the over 4700 PS and 6200 DS within the peninsula are from −18.1 to +7.5 mm/year. The MT-InSAR data suggest a complex displacement pattern across the volcano edifice, including local-scale land surface processes. In Methana town, ground stability is found on volcanoclasts and limestone for the majority of the urban area footprint while some deformation is observed in the suburban zones. At the Mavri Petra andesitic dome, time series of the exceptionally dense PS/DS network across blocks of agglomerate and cinder reveal seasonal fluctuation (5 mm amplitude) overlapping the long-term stable trend. Given the steepness of the slopes along the eastern flank of the volcano, displacement patterns may indicate mass movements. The GNSS, seismological and MT-InSAR analyses lead to a first account of deformation processes and their temporal evolution over the last years for Methana, thus providing initial information to feed into the volcano baseline hazard assessment and monitoring system.

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CO2 Injection Deformation Monitoring Based on UAV and InSAR Technology: A Case Study of Shizhuang Town, Shanxi Province, China

Remote Sensing ◽

10.3390/rs14010237 ◽

2022 ◽

Vol 14 (1) ◽

pp. 237

Author(s):

Tian Zhang ◽

Wanchang Zhang ◽

Ruizhao Yang ◽

Dan Cao ◽

Longfei Chen ◽

...

Keyword(s):

Carbon Capture ◽

Surface Deformation ◽

Deformation Monitoring ◽

Shanxi Province ◽

Co2 Injection ◽

Climate Mitigation ◽

Measurement Technology ◽

Surface Model ◽

Integrated Monitoring ◽

Migration Pathway

Carbon Capture, Utilization and Storage, also referred to as Carbon Capture, Utilization and Sequestration (CCUS), is one of the novel climate mitigation technologies by which CO2 emissions are captured from sources, such as fossil power generation and industrial processes, and further either reused or stored with more attention being paid on the utilization of captured CO2. In the whole CCUS process, the dominant migration pathway of CO2 after being injected underground becomes very important information to judge the possible storage status as well as one of the essential references for evaluating possible environmental affects. Interferometric Synthetic Aperture Radar (InSAR) technology, with its advantages of extensive coverage in surface deformation monitoring and all-weather traceability of the injection processes, has become one of the promising technologies frequently adopted in worldwide CCUS projects. In this study, taking the CCUS sequestration area in Shizhuang Town, Shanxi Province, China, as an example, unmanned aerial vehicle (UAV) photography measurement technology with a 3D surface model at a resolution of 5.3 cm was applied to extract the high-resolution digital elevation model (DEM) of the study site in coordination with InSAR technology to more clearly display the results of surface deformation monitoring of the CO2 injection area. A 2 km surface heaving dynamic processes before and after injection from June 2020 to July 2021 was obtained, and a CO2 migration pathway northeastward was observed, which was rather consistent with the monitoring results by logging and micro-seismic studies. Additionally, an integrated monitoring scheme, which will be the trend of monitoring in the future, is proposed in the discussion.

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