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2. Mapping the global threat of land subsidence

Author

Universidad de Alicante. Departamento de Ingeniería Civil, Herrera García, Gerardo, Ezquerro Martín, Pablo, Tomás, Roberto, Béjar Pizarro, Marta, López-Vinielles, Juan, Rossi, Mauro, Mateos, Rosa María, Carreón-Freyre, Dora, Lambert, John, Teatini, Pietro, Cabral-Cano, Enrique, Erkens, Gilles, Galloway, Devin, Hung, Wei-Chia, Kakar, Najeebullah, Sneed, Michelle, Tosi, Luigi, Wang, Hanmei, Ye, Shujun, Universidad de Alicante. Departamento de Ingeniería Civil, Herrera García, Gerardo, Ezquerro Martín, Pablo, Tomás, Roberto, Béjar Pizarro, Marta, López-Vinielles, Juan, Rossi, Mauro, Mateos, Rosa María, Carreón-Freyre, Dora, Lambert, John, Teatini, Pietro, Cabral-Cano, Enrique, Erkens, Gilles, Galloway, Devin, Hung, Wei-Chia, Kakar, Najeebullah, Sneed, Michelle, Tosi, Luigi, Wang, Hanmei, and Ye, Shujun

Abstract

Subsidence, the lowering of Earth's land surface, is a potentially destructive hazard that can be caused by a wide range of natural or anthropogenic triggers but mainly results from solid or fluid mobilization underground. Subsidence due to groundwater depletion (1) is a slow and gradual process that develops on large time scales (months to years), producing progressive loss of land elevation (centimeters to decimeters per year) typically over very large areas (tens to thousands of square kilometers) and variably affects urban and agricultural areas worldwide. Subsidence permanently reduces aquifer-system storage capacity, causes earth fissures, damages buildings and civil infrastructure, and increases flood susceptibility and risk. During the next decades, global population and economic growth will continue to increase groundwater demand and accompanying groundwater depletion (2) and, when exacerbated by droughts (3), will probably increase land subsidence occurrence and related damages or impacts. To raise awareness and inform decision-making, we evaluate potential global subsidence due to groundwater depletion, a key first step toward formulating effective land-subsidence policies that are lacking in most countries worldwide.

Published
2021

3. Mapping the global threat of land subsidence

Author

Agencia Estatal de Investigación (España), Herrera García, Gerardo [0000-0002-6633-9184], Ezquerro Martín, Pablo [0000-0001-8667-5030], Béjar Pizarro, Marta [0000-0001-7449-4048], Herrera García, Gerardo, Ezquerro Martín, Pablo, Tomás, Roberto, Béjar Pizarro, Marta, López-Vinielles, Juan, Rossi, Mauro, Mateos Ruiz, Rosa María, Carreón Freyre, Dora, Lambert, John, Teatini, Pietro, Cabral Cano, E., Erkens, Gilles, Galloway, Devin, Hung, Wei-Chia, Kakar, Najeebullah, Sneed, Michelle, Tosi, Luigi, Wang, Hanmei, Ye, Shujun, Agencia Estatal de Investigación (España), Herrera García, Gerardo [0000-0002-6633-9184], Ezquerro Martín, Pablo [0000-0001-8667-5030], Béjar Pizarro, Marta [0000-0001-7449-4048], Herrera García, Gerardo, Ezquerro Martín, Pablo, Tomás, Roberto, Béjar Pizarro, Marta, López-Vinielles, Juan, Rossi, Mauro, Mateos Ruiz, Rosa María, Carreón Freyre, Dora, Lambert, John, Teatini, Pietro, Cabral Cano, E., Erkens, Gilles, Galloway, Devin, Hung, Wei-Chia, Kakar, Najeebullah, Sneed, Michelle, Tosi, Luigi, Wang, Hanmei, and Ye, Shujun

Published
2021

6. Study of Subsidence and Earthquake Swarms in the Western Pakistan.

Author

Jingqiu Huang, Khan, Shuhab D., Ghulam, Abduwasit, Crupa, Wanda, Abir, Ismail A., Khan, Abdul S., Kakar, Din M., Kasi, Aimal, and Kakar, Najeebullah

Subjects
STRIKE-slip faults (Geology), SEISMIC reflection method data processing, EARTHQUAKE intensity, SYNTHETIC aperture radar
Abstract

In recent years, the Quetta Valley and surrounding areas have experienced unprecedented levels of subsidence, which has been attributed mainly to groundwater withdrawal. However, this region is also tectonically active and is home to several regional strike-slip faults, including the north-south striking left-lateral Chaman Fault System. Several large earthquakes have occurred recently in this area, including one deadly Mw 6.4 earthquake that struck on 28 October 2008. This study integrated Interferometric Synthetic Aperture Radar (InSAR) results with GPS, gravity, seismic reflection profiles, and earthquake centroid-moment-tensor (CMT) data to identify the impact of tectonic and anthropogenic processes on subsidence and earthquake patterns in this region. To detect and map the spatial-temporal features of the processes that led to the surface deformation, this study used two Synthetic Aperture Radar (SAR) time series, i.e., 15 Phased Array L-band Synthetic Aperture Radar (PALSAR) images acquired by an Advanced Land Observing Satellite (ALOS) from 2006-2011 and 40 Environmental Satellite (ENVISAT) Advanced Synthetic Aperture Radar (ASAR) images spanning 2003-2010. A Small Baseline Subset (SBAS) technique was used to investigate surface deformation. Five seismic lines totaling ~60 km, acquired in 2003, were used to map the blind thrust faults beneath a Quaternary alluvium layer. The median filtered SBAS-InSAR average velocity profile supports groundwater withdrawal as the dominant source of subsidence, with some contribution from tectonic subsidence in the Quetta Valley. Results of SBAS-InSAR multi-temporal analysis provide a better explanation for the pre-, co-, and post-seismic displacement pattern caused by the 2008 earthquake swarms across two strike-slip faults. [ABSTRACT FROM AUTHOR]

Published
2016
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