Development Of Land Subsidence Research Articles

Change in regional land subsidence in Beijing after south-to-north water diversion project observed using satellite radar interferometry

ABSTRACTOver-exploitation of groundwater has caused severe land subsidence in Beijing during the past two decades. Since the middle route of South-to-North Water Diversion Project (SNWDP), the biggest water diversion project in China, started to deliver water to Beijing in December 2014, the groundwater shortage has been greatly alleviated. This study aims to analyze the impact of SNWDP on the spatiotemporal evolution of land subsidence in Beijing. Change in surface displacement in Beijing after SNWDP was retrieved and the spatiotemporal patterns of the change were analyzed based on long time-series Envisat Advanced Synthetic Aperture Radar (ASAR) (2004–2010), Radarsat-2 (2011–2014), and Sentinel-1 (2015–2017) satellite datasets using Permanent Scatterer Interferometric Synthetic Aperture Radar (PS-InSAR) techniques. Land subsidence unevenness index (LSUI) was proposed to represent the spatial unevenness of surface displacement. PS-Time approach was then adapted to examine the time series evolution of LSUI. The results showed that the InSAR measurements agree well with leveling measurements with R2 over 0.96. Although the maximum annual displacement rate reached −159.7 mm/year by 2017, over 57% of the area within 25 mm/year contour line showed decreasing or unchanged displacement rate after the south-north water delivered to Beijing. The settlement rate in Chaoyang-Dongbalizhuang (CD) subsidence center has decreased for 26 mm/year from 2011–2014 to 2015–2017. Only around 15% of the area experienced continued accelerating settlement rate through the three time periods, which was mainly located in the area with the compressible layer thickness over 190 m, while the magnitude of velocity increment considerably decreased after SNWDP. Land subsidence unevenness, represented by LSUI, developed more slowly after SNWDP than that during 2011–2014. However, LSUI at the edge of settlement funnel has kept developing and reached 1.7‰ in 2017. Decreasing groundwater level decline after SNWDP and the positive relationship (R2 > 0.74) between land subsidence and groundwater level clearly showed impacts of SNWDP on the alleviating land subsidence. Other reasons include geological background, increasing precipitation, and strict water management policies implemented during these years.

Land subsidence (2004–2013) in Changzhou in Central Yangtze River delta revealed by MT-InSAR

Land subsidence in Changzhou City in the central Yangtze River Delta of China poses a serious threat to the safety of the environment and infrastructures. Excessive groundwater withdrawal, rapid urbanisation and industrial activities contribute to land subsidence in this area. In this study, we used the multi-temporal InSAR (MT-InSAR) technique to describe the spatiotemporal characteristics of land subsidence in Changzhou. Twenty-five ENVISAT ASAR and 29 TerraSAR-X images acquired from 2004 to 2013 were used to determine the rate and temporal evolution of land subsidence. We used the ERA-Interim model instead of spatiotemporal filtering in traditional MT-InSAR to mitigate the atmospheric phase screen. The InSAR-derived results were evaluated by comparing data from three time series methods and different bands (C and X bands), and accuracy was validated through levelling surveys and GPS measurements. For three regions, a distinct subsidence pattern was observed in major industrial areas with a maximum subsidence rate of up to − 39.9 mm/year. We also characterised the spatiotemporal variations of land subsidence in major industrial areas in Changzhou. The deformation of large-scale man-made linear features, namely high-speed railways, highway networks and a bridge, was analysed. The spatiotemporal characteristics and possible reasons for the observed subsidence were discussed to provide a reference for future urban development planning in Changzhou.

Time-Series Evolution Patterns of Land Subsidence in the Eastern Beijing Plain, China

Land subsidence in the Eastern Beijing Plain has a long history and is always serious. In this paper, we consider the time-series evolution patterns of the eastern of Beijing Plain. First, we use the Persistent Scatterer Interferometric Synthetic Aperture Radar (PSI) technique, with Envisat and Radarsat-2 data, to monitor the deformation of Beijing Plain from 2007 to 2015. Second, we adopt the standard deviation ellipse (SDE) method, combined with hydrogeological data, to analyze the spatial evolution patterns of land subsidence. The results suggest that land subsidence developed mainly in the northwest–southeast direction until 2012 and then expanded in all directions. This process corresponds to the expansion of the groundwater cone of depression range after 2012, although subsidence is restricted by geological conditions. Then, we use the permutation entropy (PE) algorithm to reverse the temporal evolution pattern of land subsidence, and interpret the causes of the phenomenon in combination with groundwater level change data. The results show that the time-series evolution pattern of the land subsidence funnel edge can be divided into three stages. From 2009 to 2010, the land subsidence development was uneven. From 2010 to 2012, the land subsidence development was relatively even. From 2012 to 2013, the development of land subsidence became uneven. However, subsidence within the land subsidence funnel is divided into two stages. From 2009 to 2012, the land subsidence tended to be even, and from 2012 to 2015, the land subsidence was relatively more even. The main reason for the different time-series evolution patterns at these two locations is the annual groundwater level variations. The larger the variation range of groundwater is, the higher the corresponding PE value, which means the development of the land subsidence tends to be uneven.

Optimum design of level monitoring points for land subsidence

Land subsidence caused by long-term over-exploitation of groundwater is the main geological disaster in the plain area of Beijing, China. To obtain accurate and dynamic monitoring information on land subsidence, primary level measurement is carried out every year. However, there are shortcomings in the existing level monitoring network and development of land subsidence, which require optimization of the level monitoring network for land subsidence. Using a GIS analysis method, a zonal map of influencing factors was created by overlaying three thematic maps including hydrogeological units; the decline rate of the groundwater level in the main mining layer; and the thickness of the compressible layer. The data were classified into 448 zones. Based on the zoning map, we created an optimal design for the location of level monitoring points, locating 220 new points. Kriging interpolation error variance was chosen to evaluate map accuracy. Standard deviation contour maps of the existing level network and the optimized level network were created, and the results showed that the error of the optimized level network was smaller than the existing level network. The method proposed by this paper was reasonable for optimizing a level monitoring network for land subsidence.

Activity Characteristics and Safety distance of Gaoliying Ground Fissure in Beijing

In all ground fissures in Beijing, Gaoliying Ground Fissure has characteristics of highly activity, and it cause serious damages on constructoins. With the distribution as well as the development of land subsidence and the change of the groundwater level, a series of work has been conducted to explain the mechanism of the formation of Gaoliying Ground Fissure. For example, field damage investigations and trench observations were used to define the affected distance of ground fissure; three-dimensional deformation was monitored to determine active characteristic of ground fissure. This paper points out that Gaoliying ground fissure is controlled by Huangzhuang-Gaoliying Fault, which mainly moves in the vertical direction. The rapid decrease of the ground water level greatly increases the development of ground fissure. The distance of damaged zones affected by ground fissure in the hanging-wall of the fault reaches 49.5m, and the distance of damaged zones in the footwall of the fault is 17.5 m. A suggested safety distance of type-one and type-two buildings is 100 m. For type-three buildings, the suggested safety distance is 80 m.

Phase difference between groundwater storage changes and groundwater level fluctuations due to compaction of an aquifer-aquitard system

Drainage and deformation of intercalated confining layers due to internal stress change (discharge/recharge cycle) in an aquifer-aquitard system not only can have great effects on the groundwater storage (GWS), but also can cause unsynchronized water level (WL) fluctuations. The phase relationship between GWS and WL is crucial for the accuracy and attribution of GWS changes. We identify the dominating episodic components of GWS and WL through the Singular Spectrum Analysis (SSA) analysis and Harmonic analysis. First, we analyzed a generic aquifer-aquitard system using numerical simulations which showed that the dissipation of overpressure from the aquitard and flow from it is the inherent cause of a phase shift between the GWS and WL observations. Water released from confining layers with compaction time constant of zero (no-delay) to century time scale results in detected phase shift between total GWS and WL in the aquifer. Then, we analyzed the complex and varied phase relationship between GWS derived using the Gravity Recovery and Climate Experiment (GRACE) data and measured WL time series in the subsiding North China Plain (NCP) aquifer. The spatially varied phase relationship between GWS and measured WL is reasonably related to varied land subsidence development features and may be related with the compaction time constant and thickness of the confining layers. Results of the generic numerical model and the NCP observations suggest that elastic/inelastic response need to be considered in the interpretation and correction of GWS changes for a compacted aquifer-aquitard system.

Temporal and Spatial Evolution of Land Subsidence Induced by Groundwater Exploitation and Construction in the Eastern Chaoyang District, Beijing, China

Human activities have a large impact on land subsidence in great metropolitan areas. In this study, the RADARSAT-2 observation data over a 4-year period (from November 2010 to September 2014) is used to investigate the trends of land subsidence in the eastern Chaoyang District in Beijing, China, and to analyze the impact of human activities on it. The observation results indicate that the temporal and spatial evolutions trend of land subsidence in this area is uneven, with deformation rates ranging from − 116.52 to 7.1 mm/year. There are two large subsidence areas located in the northern part of the study area, and we find that the groundwater exploitation and deformation rates are strongly linearly correlated. The effect of construction on land subsidence has also been investigated. Over time, land subsidence is generally increased in the study area, with an exception at the Longfor Changying Galleria area, which is under construction during the observation period. Based on the time-series analysis of permanent scattered points in the 200 m buffer area, construction activities are observed to cause both land subsidence and upheaval deformation of the surrounding soil. During the construction period, the displacement of the surrounding soil is disturbed. After completion, the initial displacement of surrounding soil is tended to involve the uplift of the surrounding soil, followed by a gradual subsidence with time.

A review on land subsidence caused by groundwater withdrawal in Xi’an, China

This paper presents a review on the land subsidence caused by groundwater withdrawal in Xi’an, China. With the increasing demands of people’s livelihood and economy during the urbanization process, Xi’an has suffered severe hazards due to land subsidence caused by the excessive exploitation of groundwater since the 1960s. According to past records, the development of land subsidence in Xi’an can be divided into three stages; i) preliminary stage (1959 to 1971), ii) rapid development stage (1972 to 1990), and iii) slow development stage (1991 to present). In the 1990s, the annual groundwater withdrawal volume reached the maximum value of about 1388 × 106 m3/year, and the annual land subsidence also reached the maximum value (about 130 mm/year). The policy for controlling groundwater withdrawal was announced by the Xi’an Municipal Government in 1996, and then the land subsidence rate showed a significant descending tendency. Many researchers developed a series of approaches to yield the prediction of land subsidence caused by groundwater withdrawal, which can be divided into three categories: i) mathematical statistics approaches; ii) numerical approaches; iii) artificial intelligence approaches. Not only are the approaches’ advantages and disadvantages analyzed in this paper, but three emerging investigations on land subsidence in Xi’an are also discussed. The three emerging investigations aim to: i) analyze the relationship between land subsidence and ground fissures, ii) search the monitoring techniques available for obtaining more accurate data, and iii) investigate the effect of sand particle crushing under high stress level on the development of land subsidence.

Long-term groundwater storage changes and land subsidence development in the North China Plain (1971\u20132015)

The North China Plain (NCP) has been suffering from groundwater storage (GWS) depletion and land subsidence for a long period. This paper collects data on GWS changes and land subsidence from in situ groundwater-level measurements, literature, and satellite observations to provide an overview of the evolution of the aquifer system during 1971–2015 with a focus on the sub-regional variations. It is found that the GWS showed a prolonged declining rate of −17.8 ± 0.1 mm/yr during 1971–2015, with a negative correlation to groundwater abstraction before year ~2000 and a positive correlation after ~2000. Statistical correlations between subsidence rate and the GWS anomaly (GWSA), groundwater abstraction, and annual precipitation show that the land subsidence in three sub-regions (Beijing, Tianjin, and Hebei) represents different temporal variations due to varying driver factors. Continuous drought caused intensive GWS depletion (−76.1 ± 6.5 mm/yr) and land subsidence in Beijing during 1999–2012. Negative correlations between total groundwater abstraction and land subsidence exhibited after the 1980s indicate that it may be questionable to infer subsidence from regional abstraction data. Instead, the GWSA generally provides a reliable correlation with subsidence. This study highlights the spatio-temporal variabilities of GWS depletion and land subsidence in the NCP under natural and anthropogenic impacts, and the importance of GWS changes for understanding land subsidence development.

Spatiotemporal Evolution of Land Subsidence in the Beijing Plain 2003–2015 Using Persistent Scatterer Interferometry (PSI) with Multi-Source SAR Data

Land subsidence is one of the most important geological hazards in Beijing, China, and its scope and magnitude have been growing rapidly over the past few decades, mainly due to long-term groundwater withdrawal. Interferometric Synthetic Aperture Radar (InSAR) has been used to monitor the deformation in Beijing, but there is a lack of analysis of the long-term spatiotemporal evolution of land subsidence. This study focused on detecting and characterizing spatiotemporal changes in subsidence in the Beijing Plain by using Persistent Scatterer Interferometry (PSI) and geographic spatial analysis. Land subsidence during 2003–2015 was monitored by using ENVISAT ASAR (2003–2010), RADARSAT-2 (2011–2015) and TerraSAR-X (2010–2015) images, with results that are consistent with independent leveling measurements. The radar-based deformation velocity ranged from −136.9 to +15.2 mm/year during 2003–2010, and −149.4 to +8.9 mm/year during 2011–2015 relative to the reference point. The main subsidence areas include Chaoyang, Tongzhou, Shunyi and Changping districts, where seven subsidence bowls were observed between 2003 and 2015. Equal Fan Analysis Method (EFAM) shows that the maximum extensive direction was eastward, with a growing speed of 11.30 km2/year. Areas of differential subsidence were mostly located at the boundaries of the seven subsidence bowls, as indicated by the subsidence rate slope. Notably, the area of greatest subsidence was generally consistent with the patterns of groundwater decline in the Beijing Plain.

Regional Land Subsidence Analysis in Eastern Beijing Plain by InSAR Time Series and Wavelet Transforms

Land subsidence is the disaster phenomenon of environmental geology with regionally surface altitude lowering caused by the natural or man-made factors. Beijing, the capital city of China, has suffered from land subsidence since the 1950s, and extreme groundwater extraction has led to subsidence rates of more than 100 mm/year. In this study, we employ two SAR datasets acquired by Envisat and TerraSAR-X satellites to investigate the surface deformation in Beijing Plain from 2003 to 2013 based on the multi-temporal InSAR technique. Furthermore, we also use observation wells to provide in situ hydraulic head levels to perform the evolution of land subsidence and spatial-temporal changes of groundwater level. Then, we analyze the accumulated displacement and hydraulic head level time series using continuous wavelet transform to separate periodic signal components. Finally, cross wavelet transform (XWT) and wavelet transform coherence (WTC) are implemented to analyze the relationship between the accumulated displacement and hydraulic head level time series. The results show that the subsidence centers in the northern Beijing Plain is spatially consistent with the groundwater drop funnels. According to the analysis of well based results located in different areas, the long-term groundwater exploitation in the northern subsidence area has led to the continuous decline of the water level, resulting in the inelastic and permanent compaction, while for the monitoring wells located outside the subsidence area, the subsidence time series show obvious elastic deformation characteristics (seasonal characteristics) as the groundwater level changes. Moreover, according to the wavelet transformation, the land subsidence time series at monitoring well site lags several months behind the groundwater level change.

Microwave D-InSAR technique for assessment of land subsidence in Kolkata city, India

An effective microwave Differential Interferometric Synthetic Aperture Radar (D-InSAR) technique was used to rapidly assess the potential land subsidence with high precision by exploiting the phase difference of two temporally separated SAR data in the region of Kolkata city, India. The objective of this study is to assess land subsidence using D-InSAR technique and to delineate the regions of land subsidence caused by over exploitation of groundwater by minimising the errors by applying topographic and atmospheric corrections. The study area forms a part of Indo-Gangetic plain. Three ENVISAT Advanced Synthetic Aperture Radar (ASAR) images of the years 2003, 2007 and 2010 were acquired to study the temporal evolution of land subsidence in the study area. The phase changes due to topography in the interferograms were removed by using Shuttle Radar Topography Mission (SRTM) degital elevation model data. Medium Spectral Resolution Imaging Spectrometer (MERIS) data were applied to remove the atmospheric noise in the interferogram. The deformation fringes were observed in the northern and central part of the study area where the land subsidence was 12 and 18 mm during the years of 2003–2007 and 2007–2010. The regional variation in the piezometric head compares well with the fringes of the interferogram. This confirms over extraction of groundwater is the main cause for land subsidence in this region. Hence, it is necessary to reduce groundwater pumping and to augment rainfall recharge in northern part of the study area.

Aquifer Mechanical Properties and Decelerated Compaction in Tucson, Arizona

AbstractIn recent decades, high groundwater extraction rates, often coincident with periods of severe drought, result in the widespread decline of water levels. Overexploitation of aquifers also causes land subsidence, which poses a severe threat to infrastructure. Tucson, Arizona experiences land subsidence coupled with the depletion of groundwater, a critical water resource for the desert city. To understand the spatiotemporal evolution of land subsidence and its implications for aquifer properties, we examine long time series of surface deformation and head levels. Measurements at extensometer stations indicate rapid compaction of fine‐grained material up to 8.5 mm/yr from 1990 to 2005, which results in permanent storage volume losses up to 4.1%. The analysis of densely populated sets of interferograms generated from Envisat and RadarSAT C band acquisitions yields multitemporal maps of surface deformation at unprecedented resolution. These maps reveal that subsidence significantly slows by the late 2000s, corresponding with the implementation of artificial recharge efforts. Subsequent to groundwater level recovery, we observe a brief 6.6 year interval of residual compaction, suggesting a high vertical hydraulic conductivity, which is then shown to be up to 9.8 × 10−4 m/d. We also estimate the average elastic and inelastic skeletal storage coefficients for the aquifer system to be 3.78 × 10−3 and 6.01 × 10−3, respectively. Interferometric synthetic aperture radar shows deformation nearly ceases by 2015, likely reducing hazards associated with Earth fissuring and infrastructure damage. This study highlights successful outcomes of water management and conservation plans that preserve existing groundwater reserves and increase artificial recharge.

Measuring Spatiotemporal Features of Land Subsidence, Groundwater Drawdown, and Compressible Layer Thickness in Beijing Plain, China

Beijing is located on multiple alluvial-pluvial fans with thick Quaternary unconsolidated sediments. It has suffered serious groundwater drawdown and land subsidence due to groundwater exploitation. This study aimed to introduce geographical distribution measure methods into land subsidence research characterizing, geographically, land subsidence, groundwater drawdown, and compressible layer thickness. Therefore, we used gravity center analysis and standard deviational ellipse (SDE) methods in GIS to statistically analyze their concentration tendency, principle orientation, dispersion trend, and distribution differences in 1995 (1999), 2007, 2009, 2011, and 2013. Results show that they were all concentrated in Chaoyang District of Urban Beijing. The concentration trend of land subsidence was consistent with that of groundwater drawdown. The principle orientation of land subsidence was SW–NE, which was more similar with that of the static spatial distribution of the compressible layer. The dispersion tendency of land subsidence got closer to that of the compressible layer with its increasing intensity. The spatial distribution difference between land subsidence and groundwater drawdown was about 0.2, and that between land subsidence and compressible layer thickness it decreased from 0.22 to 0.07, reflecting that the spatial distribution pattern of land subsidence was increasingly close to that of the compressible layer. Results of this study are useful for assessing the distribution of land subsidence development and managing groundwater resources.

Spatiotemporal evolution of land subsidence around a subway using InSAR time-series and the entropy method

The underground railway network of Beijing City, China, which is an important urban infrastructure, has burgeoned with the expansion of the city. However, the influence of subway construction and operation on local subsidence has received minimal attention. By analyzing the Radarsat-2 synthetic aperture radar satellite data, and using persistent scatterer interferometry, we revealed the land subsidence characteristics along the Beijing Subway Line 6. In the context of land subsidence, the expectation (Ex) reflects the overall level of local land subsidence while the entropy (En) reflects the degree of nonuniformity of local land subsidence in time and space. By comparing the changes in Ex and En, we estimated the spatial range of the influence of the subway on local land subsidence. The influenced area was mainly located between 60 m north of the subway line and 80 m south of the subway line. Land subsidence was most strongly altered during subway construction. During operation of the subway, the deformation rates along the subway increased slightly in the first two years and were then stabilized.

Analysis of Factors in Land Subsidence in Shanghai: A View Based on a Strategic Environmental Assessment

It has been observed that in the urban center of Shanghai, land subsidence has accelerated, and the groundwater level has continued to drop even though the net withdrawn volume (NWV) of groundwater has remained unchanged since 1980. An analysis of monitoring data shows that drawdown of the groundwater level is one of the factors that have influenced land subsidence since 1980. The NWV of groundwater in urban areas, however, is not the critical factor controlling the drawdown of the groundwater level. Since the 1980s, there have been many underground works constructed in the unique strata of Shanghai, which has an interlayered structure known as a multi-aquifer-aquitard system (MAAS). Investigation into land subsidence caused by urban construction is now receiving much attention. Based on the principle of a strategic environmental assessment (SEA) for sustainable urban development, this paper presents a discussion and analysis of the factors which can influence the development of land subsidence during continued urbanization in Shanghai. The main factors include the additional loading caused by the construction of structures, the cut-off effect due to construction in aquifers, the drawdown of groundwater level caused by leakage into underground structures, and the decrease of groundwater recharge from neighboring zones. SEA is recommended for the future development of Shanghai.

Numerical simulation and prediction of regional land subsidence caused by groundwater exploitation in the southwest plain of Tehran, Iran

This study characterizes land subsidence in southwest plain of Tehran using numerical modeling and predicts the trend through 2018. Excessive groundwater withdrawal has caused severe land subsidence in Tehran; in the past 28years (1984–2012), groundwater level has decreased 11.65m. The multi-layered aquifer system in the southwestern plain of Tehran contains three aquifers and three aquitard units. The present model was developed simulation using PMWIN (MODFLOW for Windows). First, groundwater level and land subsidence were simulated for the end of 2004. The model was calibrated using hydraulic head measurements and InSAR data. The simulation results were in fairly good agreement with the measurement results. The calibrated and evaluated model was then used to assess the future evolution of land subsidence and for prediction of subsidence through the end of 2018. Numerical results show that, assuming a constant rate of pumping in the future, land subsidence in the southwestern plain of Tehran will reach 33cm by 2018. The study confirmed that land subsidence caused by groundwater pumping is a serious threat to southwest Tehran.

The interaction between land subsidence and urban development in China

Abstract. The Yangtze River Delta and North China Plain are experiencing serious land subsidence development and are also the areas that have undergone the fastest urbanization. Rapid urban development inevitably requires more water resources. However, China is a country with small per capita water resources, nonuniform distribution of water resources, and over-exploitation of groundwater – all of which are critical factors contributing to the potential for a land subsidence disaster. In addition, land subsidence has brought about elevation loss, damaged buildings, decreased safety of rail transit projects, lowered land value, and other huge economic losses and potential safety hazards in China. In this paper, Beijing, a typical northern Chinese city deficient in water, is taken as an example to explore (a) the problems of urban development, utilization of water resources, and land subsidence development; (b) the harm and influence of land subsidence hazards on urban construction; and (c) the relationship between urban development and land subsidence. Based on the results, the author has predicted the trend of urban development and land subsidence in Beijing and puts forward her viewpoints and suggestions.

Spatial-temporal variation of groundwater and land subsidence evolution in Beijing area

Abstract. Precipitation is the main recharge source of groundwater in the plain of Beijing, China. Rapid expansion of urbanization has resulted in increased built-up area and decreased amount of effective recharge of precipitation to groundwater, indirectly leading to the long-term over-exploitation of groundwater, and induced regional land subsidence. Based on the combination of meteorological data, groundwater level data, interferometric synthetic aperture radar (InSAR; specifically persistent scatterer interferometry, PSI), geographic information system (GIS) spatial analysis method and rainfall recharge theory, this paper presents a systematic analysis of spatial-temporal variation of groundwater level and land subsidence evolution. Results show that rainfall has been decreasing annually, while the exploitation of groundwater is increasing and the groundwater level is declining, which is has caused the formation and evolution of land subsidence. Seasonal and interannual variations exist in the evolution of land subsidence; the subsidence is uneven in both spatial and temporal distribution. In 2011, at the center of mapped subsidence the subsidence rate was greater than 120 mm a−1. The results revealed good correlation between the spatial distribution of groundwater level declines and subsidence. The research results show that it is beneficial to measure the evolution of land subsidence to dynamic variations of groundwater levels by combining InSAR or PSI, groundwater-level data, and GIS. This apprpach provides improved information for environmental and hydrogeologic research and a scientific basis for regional land subsidence control.

Application of multi-sensor advanced DInSAR analysis to severe land subsidence recognition: Alto Guadalentín Basin (Spain)

Abstract. Multi-sensor advanced DInSAR analyses have been performed and compared with two GPS station measurements, in order to evaluate the land subsidence evolution in a 20-year period, in the Alto Guadalentín Basin where the highest rate of man-induced subsidence (> 10 cm yr−1) of Europe had been detected. The control mechanisms have been examined comparing the advanced DInSAR data with conditioning and triggering factors (i.e. isobaths of Plio-Quaternary deposits, soft soil thickness and piezometric level).