Groundwater depletion in North West India and its response on crustal deformation

Abstract The Gravity Recovery and Climate Experiment (GRACE) measurements of the time‐variable gravity field and mass change have helped identify regions of water reservoirs over land, ice and ocean, as well as in locating areas affected by drought and groundwater over‐extraction. Studies indicate depletion in groundwater resources in North West (NW) India in the past 20 years due to over‐extraction from agricultural activities. The Global Positioning System (GPS) measurements in the region show the signature of crustal deformation caused by groundwater depletion‐induced mass change. Here, we report the vertical deformation from four continuous GPS sites within NW India, which show uplift rates of 1.5–4.2 ± 0.7 mm/year. We observed a significant correspondence between the rainfall pattern, mass change derived from GRACE measurements, GPS measurements‐derived deformation and well‐level changes. Despite some marginal increase in rainfall in the past 3–4 years, the region is still experiencing over‐extraction of groundwater due to increased demand. Although the tectonic regime of the Delhi Aravalli fold belt paleo‐structure mainly controls the earthquakes in and around the Delhi region, their occurrence appears to be influenced by groundwater over‐extraction, as the uplift in the region implies unclamping of the faults, which promotes failure.