Land subsidence is a major concern in vastly growing metropolitans worldwide. The most serious risks in this scenario are linked to groundwater extraction and urban development. Pakistan’s fourth-largest city, Rawalpindi, and its twin Islamabad, located at the northern edge of the Potwar Plateau, are witnessing extensive urban expansion. Groundwater (tube-wells) is residents’ primary daily water supply in these metropolitan areas. Unnecessarily pumping and the local inhabitant’s excessive demand for groundwater disturb the sub-surface’s viability. The Persistent Scatterer Interferometry Synthetic Aperture Radar (PS-InSAR) approach, along with Sentinel-1 Synthetic Aperture Radar (SAR) imagery, were used to track land subsidence in Rawalpindi-Islamabad. The SARPROZ application was used to study a set of Sentinel-1 imagery obtained from January 2019 to June 2021 along descending and ascending orbits to estimate ground subsidence in the Rawalpindi-Islamabad area. The results show a significant increase (−25 to −30 mm/yr) in subsidence from −69 mm/yr in 2019 to −98 mm/yr in 2020. The suggested approach effectively maps, detects, and monitors subsidence-prone terrains and will enable better planning, surface infrastructure building designs, and risk management related to subsidence.

The Wadhrai granite stock is a part of the Nagar Parkar Igneous Complex, an extension of the Neoproterozoic Malani Igneous Suite of western Rajasthan. It is occupied by a petrographically uniform granite comprising perthite, plagioclase, quartz, with small quantities of biotite, opaque oxides, titanite, and secondary minerals. The rocks are sparingly porphyritic and contain dykes of microgranite, aplite, and rare pegmatite. In the south-central part, parallel sheets and swarms of mafic dykes, and in the western part very fine-grained felsic sheets intrude the body. The granite is metaluminous to peraluminous and characterized by high silica (73–76 wt%), and alkalis (7–9 wt%), and low CaO (0.15–1.4 wt%), MgO (0.15–0.38 wt%), Th (7–12 ppm), and U (1–2 ppm). On geochemical discriminant diagrams, it classifies mostly as A-type (with rather high Y/Nb (8.6 to 2.4, average 5.2) and low Nb/Ga and Ce (typical of A2-type), but sparingly as I-type. Chondrite-normalized patterns show enrichment in LREE over HREE, and small negative Eu anomalies, whereas mantle-normalized spidergrams display higher LILE over HFSE, distinct troughs for Nb, Sr, P, Ti, and spikes for La, Ce, Nd, Sm and Tb. The granite magma was possibly derived from a tonalite-granodiorite-dominated crustal source. Based on the above-mentioned geochemical evidence, it is interpreted that the source rocks of the magma of the Wadhrai granite likely developed initially in a continental margin subduction setting and underwent partial melting in a continental extensional environment.