Spatial Analysis of Land Subsidence in the San Luis Potosi Valley Induced by Aquifer Overexploitation Using the Coherent Pixels Technique (CPT) and Sentinel-1 InSAR Observation

Abstract

The San Luis Potosi metropolitan area has suffered considerable damage from land subsidence over the past decades, which has become visible since 1990. This paper seeks to evaluate the effects of groundwater withdrawal on land subsidence in the San Luis Potosi Valley and the development of surface faults due to the differential compaction of sediments. For this purpose, we applied the Coherent Pixels Technique (CPT), a Persistent Scatterer Interferometry (PSI) technique, using 112 Sentinel-1 acquisitions from October 2014 to November 2019 to estimate the deformation rate. The results revealed that the deformation areas in the municipality of Soledad de Graciano Sánchez mostly exhibit subsidence values between −1.5 and −3.5 cm/year; whereas in San Luis Potosi these values are between −1.8 and −4.2 cm/year. The PSI results were validated by five Global Navigation Satellite System (GNSS) benchmarks available, providing a data correlation between the results obtained with both techniques of 0.986. This validation suggests that interferometric derived deformations agree well with results obtained from GNSS data. The strong relationship between trace fault, land subsidence,e and groundwater extraction suggests that groundwater withdrawal is resulting in subsidence induced faulting, which follows the pattern of structural faults buried by sediments.

Delineation of Groundwater Potential Zones (GWPZs) in a Semi-Arid Basin through Remote Sensing, GIS, and AHP Approaches

“…The SLPB is a graben structure filled over the years with volcanic rocks, lava flows, pyroclastic material, and alluvial and lacustrine sediments, similar to other northeastern basins of Mexico [37,44,45]. The oldest rocks belong to the Cretaceous from the Sierra Madre Oriental.…”

“…Cenozoic volcanic rocks (including rhyolites and ignimbrites) overlaid these Cretaceous rocks. They presented the Cenozoic tectonic trademark, formed by a series of NW-SE normal faults with a dominant and regional inclination between 15-20 • NE [20,45].…”

“…A Quaternary granular sequence (alluvial, sands, silts, gravels, and clay) was deposited on top of the volcanic units as basin-fill material [45,48]. This sequence includes a compact, fine-grained clay-sand layer of low hydraulic conductivity (10 −9 m/s) under most flat areas (except at the edges).…”

ValInSAR: A Systematic Approach for the Validation of Differential SAR Interferometry in Land Subsidence Areas

“…From 1970, when groundwater exploitation began, piezometric levels in wells decreased up to 0.9 m per year, causing differential compaction of sediments and consequently land subsidence and ground fracturing, that became visible in the early 1990s [96], [98]. In recent studies, DInSAR has measured deformation rates up to -4.2 cm/year in the centre of the valley [6]. In this research, Continuous GNSS observations and GNSS benchmarks were used to perform the DInSAR data validation.…”

Improving CPT-InSAR Algorithm with Adaptive Coherent Distributed Pixels Selection

“…The coherent pixels technique InSAR (CPT-InSAR) [16][17][18], which combines the advantages of PS-InSAR and SBAS-InSAR, was proposed in order to reduce the errors caused by the small number of images and to improve the accuracy of estimation parameters. CPT-InSAR is also able to retrieve linear and nonlinear components of movement from a set of low resolution interferograms, estimating DEM errors and atmospheric artifacts at the same time, and it is widely used in surface deformation monitoring [19][20][21]. However, when the selected coherence threshold is high, CPT cannot select a sufficient number of points in the low coherence region, which will cause observation points to be disconnect [22].…”