The experience of monitoring the land subsidence in urban areas by radar satellite interferometry on the example of St. Petersburg

2020 ◽  
Vol 64 (4) ◽  
pp. 399-408
Author(s):  
Shirshova V. ◽  

Разработана и опробована методика мониторинга на основе метода радиолокационной спутниковой интерферометрии с применением открытых данных радиолокационного спутника Sentinel-1. Обработка радиолокационных снимков была реализована на открытом программном обеспечении SNAP. В результате были получены 40 карт вертикальных смещений города Санкт-Петербург. На основе геоинформационного программного обеспечения QGIS был произведен анализ полученных карт смещений и визуализация результатов интерферометрической обработки.

2019 ◽  
Vol 85 ◽  
pp. 07015 ◽  
Author(s):  
Alina Radutu ◽  
Radu Constantin Gogu

Land subsidence affects urban areas worldwide. Sometimes it could be driven by intensive groundwater withdrawal to assure different urban needs and functionalities. Some of these urban areas have a long history of subsidence that covers almost a century. The aim of this paper is to present the evolution of several urban areas affected by land subsidence, the methods used to monitor vertical displacements along the decades in relationship to the groundwater extraction associated to the urban expansion, and the mitigation techniques used for countering the effects of intensive groundwater withdrawal. Even the originally applied subsidence monitoring methods (such as geometric levelling) are still very sensitive, in terms of time consuming, covered area, and financial effort, these methods might be complemented by new methods based on Synthetic Aperture Radar Interferometry (InSAR). InSAR methods show also a significant progress during the last decades when considering the subsidence sensed order of magnitude.


2021 ◽  
Vol 873 (1) ◽  
pp. 012044
Author(s):  
I Gumilar ◽  
TP. Sidiq ◽  
I Meilano ◽  
B Bramanto ◽  
G Pambudi

Abstract Gedebage district is presently experiencing rapid and mass infrastructure development and becoming one of the developed districts in Bandung, Indonesia. A football stadium, several luxury housing, the grand mosque of West Java province, and a business center have been built in this district. However, it is well known that the Gedebage district has turned into one of the Bandung districts that suffers from land subsidence phenomena. Since 2000, the Gedebage district has suffered land subsidence at an average rate of 10 cm per year and becoming one of the fastest sinking districts in Bandung. This fast land subsidence phenomenon is suspected of affecting the infrastructure in this district. Therefore, this work aims to capture the current subsidence rate in the Gedebage district using the geodetic approach of the combination of the Global Navigation Satellite System (GNSS) with Interferometric Synthetic Aperture Radar (InSAR) and investigate the impact of land subsidence on infrastructures in Gedebage district. We use GNSS campaign datasets from the years 2016 and 2019. Each GNSS campaign was performed at least 10-12 hours of observations. We also utilize a similar period of 2016 to 2019 for the InSAR datasets. Utilizing both GNSS and InSAR datasets, we can capture the subsidence with the rate reaching 4 -15 cm per year between 2016 and 2019, and it occurs uniformly in this district. The impact of land subsidence occurred in almost all urban areas in the Gedebage district. These impacts include cracks in buildings, bridges and roads, and also tilted buildings.


2019 ◽  
Vol 11 (24) ◽  
pp. 7162 ◽  
Author(s):  
Yong-Xia Wu ◽  
Tian-Liang Yang ◽  
Pei-Chao Li ◽  
Jin-Xin Lin

In this paper, the hydrogeological features of Quaternary deposits in Shanghai as well as the characteristics of groundwater withdrawal and recharge in urban areas are investigated. One phreatic aquifer and five confined aquifers (AqI to AqV) are present in Shanghai, and these aquifers are separated by five aquitards. Groundwater withdrawal from confined aquifers has resulted in land subsidence in Shanghai. To control land subsidence, the groundwater withdrawal volume has been decreased, and the groundwater recharge volume has been increased since 1965. Correspondingly, the pressure head in confined aquifers has risen. The groundwater head increases in shallow aquifers may impact underground structures and lead to the following issues: i) an increased risk of water in-rushing hazards caused by confined water pressure during structural excavations and ii) an increased instability risk caused by groundwater buoyancy. Both excavation anti-uprush and underground structure anti-floating are discussed in this paper. Based on the risk possibilities, the anti-uprush of the excavation is divided into six regions, and the structural anti-floating is divided into five regions in urban areas. To avoid geohazards caused by the rise in groundwater head, real-time monitoring of the pressure head in AqII is recommended.


2021 ◽  
Author(s):  
Wahyu Luqmanul Hakim ◽  
Seul Ki Lee ◽  
Chang-Wook Lee

<div> <p>Floods in Pekalongan, Indonesia often occur due to the overflowing of river water during heavy monsoon rain. While the northern coast area of Pekalongan which located adjacent to the Java sea was affected by coastal floods due to sea-level rise. The flood conditions in every area were exacerbated by land subsidence and lead to coastal inundation. Monitoring land subsidence in Pekalongan becomes important to predict the further possible land subsidence occurrence area and mitigate the possible hazard caused by land subsidence. The analysis of land subsidence is much easier since the existence of radar satellites. This study used Synthetic Aperture Radar (SAR) datasets from the Sentinel-1 radar satellite between 2017 and 2020 in descending tracks. The data was processed through a time-series Interferometry SAR (InSAR) method based on the Stanford Methods for Persistent Scatterer (StaMPS) algorithm to provide accurate measurements over large areas by improving the selection of coherent pixels and reducing atmosphere noises. The result of persistent scatterer points then spatially clustered using Optimized Hot Spot Analysis (OHSA) to estimate significant points statistically and define them as the hot spot points. The results of time-series vertical deformation in Pekalongan were compared with the GPS station measurements. The comparison showed a good correlation in deformation patterns between time-series InSAR and GPS measurements. Our study revealed that the land subsidence in Pekalongan occurred mostly in settlement areas under the young alluvium soil which did not support the maximum compression from many buildings. Another cause of land subsidence in Pekalongan was the excessive groundwater extraction in the settlement areas could reduce the effective stress of pore pressure and lead to compaction in the aquifer areas. The time-series method that using the StaMPS algorithm and Optimized Hot Spot Analysis in this study can be applied for monitoring land subsidence in another area and from all-terrain.</p> </div>


2021 ◽  
Author(s):  
Pablo Ezquerro ◽  
Gerardo Herrera-García ◽  
Roberto Tomás ◽  
Marta Béjar-Pizarro ◽  
Juan López-Vinielles ◽  
...  

<p>Land subsidence associated with groundwater withdrawal is often an underestimated geological hazard that may produce important damage to buildings and infrastructure, change flood risk in some areas, and cause loss of groundwater storage capacity. In the current framework of global climate change, the increasing agricultural and urban use of groundwater resources is a growing problem, especially in arid and semiarid areas. Because monitoring subsidence in these areas is important for management, but early detection is difficult due to slow displacement rates, we developed global groundwater induced land subsidence probability maps.  Global land subsidence probability was calculated by applying statistical methods to a set of susceptible geographical, environmental and geological properties based on known, documented subsidence affected areas. Highest values of subsidence probability are concentrated over flat areas composed of unconsolidated sediments, and in agricultural or urban areas subject to prolonged dry periods. Including water scarcity and groundwater use data resulted in an estimation of a proxy land subsidence hazard. Calculated probability does not imply that all the high value areas are currently incurring land subsidence, but it can alert policymakers and groundwater managers to areas that have potential exposure to subsidence hazards and warrant monitoring. The complete results of this work are published in Science Policy Forum section under the title “Mapping the global threat of land subsidence” DOI: 10.1126/science.abb8549</p>


Author(s):  
Hasanuddin Z. Abidin ◽  
Heri Andreas ◽  
Irwan Gumilar ◽  
Bambang D. Yuwono ◽  
Dodid Murdohardono ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document