Mapping Land Subsidence Related to Underground Coal Fires in the Wuda Coalfield (Northern China) Using a Small Stack of ALOS PALSAR Differential Interferograms

Coal fires, land subsidence, roof collapse, and other life-threatening risks are a predictable phenomenon for the mineworkers and the neighbourhood population in coalfields. Jharia Coalfields in India are suffered heavily from land subsidence and coal fires for over a century. In addition to the loss of precious coal reserves, this has led to severe damage to the environment, livelihood, transportation, and precious lives.Such incidents highlight the dire need for a well-defined methodology for risk analysis for the coalfield. In this study, we regenerated a Land Use Land Cover map prepared using Indian Remote Sensing satellite imagery and ground survey. Persistent Scatterer Interferometry analysis using Sentinel -1 images was carried out to study the land subsidence phenomenon between Nov 2018 and Apr 2019. For the same study period, coal fire zones were identified with Landsat &#8211; 8 thermal band imagery. Integration of coal fire maps, subsidence velocity maps, and land use maps was further implemented in a geographical information background environment to extract the high-risk zones. These high-risk areas include residential areas, railways, and mining sites, requiring immediate attention.The results show that the coal mines are affected by subsidence of up to 20 cm/yr and a temperature anomaly of nearly 20oC is noticed. A high-risk zone of almost 18 sq. km. was demarcated with Kusunda, Gaslitand, and West Mudidih collieries being the most critically affected zones in the Coal mines. The study demonstrates the potential to combine data from multiple satellite sensors to build a safer ecosystem around the coal mines. &#160;

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Spatio-temporal changes of underground coal fires during 2008–2016 in Khanh Hoa coal field (North-east of Viet Nam) using Landsat time-series data

Journal of Mountain Science ◽

10.1007/s11629-018-4997-z ◽

2018 ◽

Vol 15 (12) ◽

pp. 2703-2720 ◽

Cited By ~ 1

Author(s):

Tuyen Danh Vu ◽

Thanh Tien Nguyen

Keyword(s):

Time Series ◽

Time Series Data ◽

Temporal Changes ◽

Series Data ◽

Viet Nam ◽

Coal Field ◽

North East ◽

Coal Fires ◽

Spatio Temporal ◽

Underground Coal Fires

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Multi-Sensor InSAR Analysis of Progressive Land Subsidence over the Coastal City of Urayasu, Japan

Remote Sensing ◽

10.3390/rs10081304 ◽

2018 ◽

Vol 10 (8) ◽

pp. 1304 ◽

Cited By ~ 13

Author(s):

Yusupujiang Aimaiti ◽

Fumio Yamazaki ◽

Wen Liu

Keyword(s):

Synthetic Aperture Radar ◽

Survey Data ◽

Land Subsidence ◽

Ground Deformation ◽

Tohoku Earthquake ◽

Synthetic Aperture ◽

Alos Palsar ◽

The 2011 Tohoku Earthquake ◽

L Band ◽

Aperture Radar

In earthquake-prone areas, identifying patterns of ground deformation is important before they become latent risk factors. As one of the severely damaged areas due to the 2011 Tohoku earthquake in Japan, Urayasu City in Chiba Prefecture has been suffering from land subsidence as a part of its land was built by a massive land-fill project. To investigate the long-term land deformation patterns in Urayasu City, three sets of synthetic aperture radar (SAR) data acquired during 1993–2006 from European Remote Sensing satellites (ERS-1/-2 (C-band)), during 2006–2010 from the Phased Array L-band Synthetic Aperture Radar onboard the Advanced Land Observation Satellite (ALOS PALSAR (L-band)) and from 2014–2017 from the ALOS-2 PALSAR-2 (L-band) were processed by using multitemporal interferometric SAR (InSAR) techniques. Leveling survey data were also used to verify the accuracy of the InSAR-derived results. The results from the ERS-1/-2, ALOS PALSAR and ALOS-2 PALSAR-2 data processing showed continuing subsidence in several reclaimed areas of Urayasu City due to the integrated effects of numerous natural and anthropogenic processes. The maximum subsidence rate of the period from 1993 to 2006 was approximately 27 mm/year, while the periods from 2006 to 2010 and from 2014 to 2017 were approximately 30 and 18 mm/year, respectively. The quantitative validation results of the InSAR-derived deformation trend during the three observation periods are consistent with the leveling survey data measured from 1993 to 2017. Our results further demonstrate the advantages of InSAR measurements as an alternative to ground-based measurements for land subsidence monitoring in coastal reclaimed areas.

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Determining hydrological barriers in wetlands with InSAR methods: several iconic cases worldwide

10.5194/egusphere-egu21-14620 ◽

2021 ◽

Author(s):

Fernando Jaramillo ◽

Dan Liu ◽

Saeid Aminjafari ◽

Xuan Wang

Keyword(s):

Large Scale ◽

Wetland Management ◽

Northern China ◽

Water Levels ◽

Interferometric Synthetic Aperture Radar ◽

Alos Palsar ◽

Critical Determinant ◽

Wetland Functions ◽

Dry Seasons ◽

Baiyangdian Wetland

Hydrological connectivity is a critical determinant of wetland functions and ecosystems by controlling the movement of biogeochemical elements within wetlands and the flow of water between their hydrological units. Hydrological barriers exist when this connectivity is impaired, either by man-made infrastructure, agriculture developments, or naturally restricted by soil and ground composition. Determining hydrological barriers in wetlands is challenging due to the costs of high-resolution and large-scale monitoring, but radar observations can become a useful tool for such task. We here use an Interferometric Synthetic Aperture Radar (InSAR) to identify hydrological barriers in several iconic wetlands worldwide, with particular focus on the Baiyangdian wetland system in Northern China. For the first, we use Sentinel 1A and 1B data covering the period 2016-2019, while for the rest we rely on ALOS PALSAR data. We calculated profiles of water level change across hydrological transects showing high coherence and visualized them in maps. For instance, in the case of the Baiyangdian wetland, we find that of the 70 transects studied, 11% of all transects are permanently disconnected by hydrological barriers across all interferograms and 58% of the transects are conditionally disconnected. The occurrence of hydrological barriers varies between wetlands, with permanent barriers more related to ditches, infrastructure and the specific wetland landscape, and conditional barriers more to low water levels during dry seasons. This study highlights the potential of the application of wetland InSAR to determine hydrological barriers for wetland management and restoration.

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