Combined Effect of Mining, Subsidence and Coal Fires in Jharkhand, India
Investigated using Satellite Remote Sensing and Data Fusion
Abstract
The coal fires that started over a century ago in Jharia Coal Fields
constitute a significant threat to the coal reserves, infrastructure,
and residents’ lives. The fires burn underground coal leaving the
surface with no support, leading to land subsidence and roof collapse.
This will have a multiplier effect as it creates cracks and crevices
that pump in more oxygen to aggravate the coal fires further. Despite
the various measures taken by authorities, coal fires and land
subsidence still have an increasing presence. In this study, we
investigated the two hazards and their impact on the coal mines and
surrounding settlements. We observed the subsidence and coal fires in
the study area with the help of Persistent Scatterer Interferometry
analysis of Sentinel-1 images and Temperature anomaly mapping of Thermal
Infrared Imagery from Landsat-8, respectively. The subsidence velocity
results and the coal fire zones are analysed, and a significant spatial
overlap of both hazards is noticed. A few key locations severely
affected by both the hazards are identified and examined to understand
the mutual effect of coal fires and land subsidence. The subsidence of
up to 20 cm/yr is observed in the study area. The results show that
nearly 80% of the subsiding area is also affected by coal fires.
Kusunda, Bararee and Keshalpur collieries are critically affected by
both the hazards and need immediate intervention. Subsidence and coal
fires extending towards the residential zones in several collieries is a
matter of concern. In conclusion, the study presents an efficient
methodology for multi-hazard monitoring, and the findings assist the
authorities in enforcing appropriate disaster management strategies.