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Radar interferometry techniques for the study of ground subsidence phenomena: a review of practical issues through cases in Spain 总被引：5，自引：0，他引：5
R. Tomás R. Romero J. Mulas J. J. Marturià J. J. Mallorquí J. M. Lopez-Sanchez G. Herrera F. Gutiérrez P. J. González J. Fernández S. Duque A. Concha-Dimas G. Cocksley C. Castañeda D. Carrasco P. Blanco 《Environmental Earth Sciences》2014,71(1):163-181
Subsidence related to multiple natural and human-induced processes affects an increasing number of areas worldwide. Although this phenomenon may involve surface deformation with 3D displacement components, negative vertical movement, either progressive or episodic, tends to dominate. Over the last decades, differential SAR interferometry (DInSAR) has become a very useful remote sensing tool for accurately measuring the spatial and temporal evolution of surface displacements over broad areas. This work discusses the main advantages and limitations of addressing active subsidence phenomena by means of DInSAR techniques from an end-user point of view. Special attention is paid to the spatial and temporal resolution, the precision of the measurements, and the usefulness of the data. The presented analysis is focused on DInSAR results exploitation of various ground subsidence phenomena (groundwater withdrawal, soil compaction, mining subsidence, evaporite dissolution subsidence, and volcanic deformation) with different displacement patterns in a selection of subsidence areas in Spain. Finally, a cost comparative study is performed for the different techniques applied. 相似文献
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Analysis of urbanisation-induced land subsidence in Shanghai 总被引：2，自引：1，他引：1
Since 1980, land subsidence has accelerated and groundwater levels have decreased in the centre of Shanghai, although the net withdrawn volume of groundwater has not increased. Theoretical analysis of the monitored data shows that the decrease in the groundwater level is the primary reason for the observed land subsidence. Meanwhile, the net withdrawn volume of groundwater in the urban centre of Shanghai has not increased during this period. Many underground structures have been constructed in the multi-aquifer-aquitard system of Shanghai since 1980. This paper discusses the factors related to the development of land subsidence during the process of urbanisation in Shanghai during the past 30?years. These factors include additional load during and after structure construction, the cut-off and/or partial cut-off effect of underground structures in aquifers, the decrease in the groundwater level due to leakage of underground structures and the reduction in recharge of groundwater from the surroundings. 相似文献
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The aim of this study was to provide a contribution to seismic hazard assessment of the Salento Peninsula (Apulia, southern Italy). It is well known that this area was struck by the February 20, 1743, earthquake (I 0 = IX and M w = 7.1), the strongest seismic event of Salento, that caused the most severe damage in the towns of Nardò (Lecce) and Francavilla Fontana (Brindisi), in the Ionian Islands (Greece) and in the western coast of Albania. It was also widely felt in the western coast of Greece, in Malta Islands, in southern Italy and in some localities of central and northern Italy. Moreover, the area of the Salento Peninsula has also been hit by several low-energy and a few high-energy earthquakes over the last centuries; the instrumental recent seismicity is mainly concentrated in the western sector of the peninsula and in the Otranto Channel. The Salento area has also experienced destructive seismicity of neighboring regions in Italy (the Gargano Promontory in northern Apulia, the Southern Apennines chain, the Calabrian Arc) and in the Balkan Peninsula (Greece and Albania). Accordingly, a critical analysis of several documentary and historical sources, as well as of the geologic–geomorphologic ground effects due to the strong 1743 Salento earthquake, has been carried out by the authors in this paper; the final purpose has been to re-evaluate the 1743 MCS macroseismic intensities and to provide a list of newly classified localities according to the ESI-07 scale on the base of recognized Earthquake Environmental Effects. The result is a quite different damage scenario due to this earthquake that could raise the seismic potential currently recognized for the Salento area, and consequently upgrade the seismic hazard classification of the Salento. Indeed it is important to remind that currently, despite the intense earthquake activity recorded not only in the Otranto Channel, but especially in Greece and Albania, this area is classified in the least dangerous category of the Seismic Classification of the Italian territory (IV category).
相似文献5.
The aim of this study was to provide a contribution to seismic hazard assessment of the Salento Peninsula (Apulia, southern Italy). It is well known that this area was struck by the February 20, 1743, earthquake (I 0 = IX and M w = 7.1), the strongest seismic event of Salento, that caused the most severe damage in the towns of Nardò (Lecce) and Francavilla Fontana (Brindisi), in the Ionian Islands (Greece) and in the western coast of Albania. It was also widely felt in the western coast of Greece, in Malta Islands, in southern Italy and in some localities of central and northern Italy. Moreover, the area of the Salento Peninsula has also been hit by several low-energy and a few high-energy earthquakes over the last centuries; the instrumental recent seismicity is mainly concentrated in the western sector of the peninsula and in the Otranto Channel. The Salento area has also experienced destructive seismicity of neighboring regions in Italy (the Gargano Promontory in northern Apulia, the Southern Apennines chain, the Calabrian Arc) and in the Balkan Peninsula (Greece and Albania). Accordingly, a critical analysis of several documentary and historical sources, as well as of the geologic–geomorphologic ground effects due to the strong 1743 Salento earthquake, has been carried out by the authors in this paper; the final purpose has been to re-evaluate the 1743 MCS macroseismic intensities and to provide a list of newly classified localities according to the ESI-07 scale on the base of recognized Earthquake Environmental Effects. The result is a quite different damage scenario due to this earthquake that could raise the seismic potential currently recognized for the Salento area, and consequently upgrade the seismic hazard classification of the Salento. Indeed it is important to remind that currently, despite the intense earthquake activity recorded not only in the Otranto Channel, but especially in Greece and Albania, this area is classified in the least dangerous category of the Seismic Classification of the Italian territory (IV category). 相似文献
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基于ANN的苏锡常地裂缝预测研究 总被引：5，自引：0，他引：5
伴随着地面沉降灾害的发生,地裂缝作为一种新的地质灾害出现在苏锡常平原上,已有十多年历史,给地区发展造成严重危害。作者在较详细地阐述区域地质背景基础上,着重分析了地下水位和地面沉降在地裂缝形成中的作用。确定了“起伏的基底外加地下水位和地面沉降作用”这一地裂缝成灾模式。研究认为地裂缝的发生与地下水及地面沉降之间不存在简单的线性关系。而是二者共同作用的结果,同时需要有量的配合。初步确定了水位埋深50m,地面沉降量达500mm这样一个苏锡常地区地裂缝的易发环境。通过文章的研究,使得苏锡常地区地裂缝的产生机制更加清晰。文中一些定性和半定量的分析结论将对该地区地裂缝防治区划产生指导作用。 相似文献
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Jichun Wu Xiaoqing Shi Yuqun Xue Yun Zhang Zixin Wei Jun Yu 《Environmental Geology》2008,55(8):1725-1735
Land subsidence in China occurs predominantly in 17 provinces (cities) situated in the eastern and middle regions of the country,
including Shanghai, Tianjin and Jiangsu, and Hebei provinces. It is primarily caused by groundwater overpumping. One of the
areas most severely affected by land subsidence is the Yangtze Delta, most of which consists of Shanghai City, the Su-Xi-Chang
area (Suzhou, Wuxi and Changzhou cities) of Jiangsu Province, and the Hang-Jia-Hu area (Hangzhou, Jiaxing and Huzhou cities)
of Zhejiang Province. The excessive exploitation of groundwater forms in a large regional cone of depression and, consequently,
land subsidence is also regional, currently centered in the Shanghai and Su-Xi-Chang areas. In 2002, the maximum cumulative
subsidence of Shanghai, Su-Xi-Chang and Hang-Jia-Hu were 2.63 m, 2.00 and 1.06 m, respectively. The land subsidence area is
continuing to expand throughout the Yangtze Delta. To study the characteristics and the pattern of this land subsidence, the
government has implemented a monitoring system involving the placement of 37 groups of extensometers (layers marks) and drilling
of more than 1000 observation wells. These provide an invaluable historical record of deformation and pore water pressure
and facilitate studies on the special features of soil deformation when the groundwater level changes due to pumping. Several
measures have been taken in recent years to control the development of the land subsidence in the different areas; these include
groundwater injection, prohibition of pumping deep confined groundwater, and an adjustment of the pumping depth and magnitude
of the groundwater withdrawn. At present, although the subsidence area is still increasing slowly, the subsidence rate is
controlled. 相似文献
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沧州市地面沉降研究及防治对策 总被引：13，自引：1，他引：13
河北省沧州市发生了严重的地面沉降，至2001年的30年间，沧州市沉降中心的地面沉降量已超过2m，导致了城市内涝积水，河床下沉，影响南水北调等引水工程安全。经研究提出了地下水等液体资源的过量开采是诱发地面沉降的主要原因，而厚大的粘性土层为地面沉降的发生提供了物质基础。粘性土的释水压缩的永久性决定了地面沉降的不可逆性。通过不同时期沧州市地面沉降累计沉降量和地下水位降深的相关分析，建立了二者之间的相关公式，提出了警戒水位降深(临界)值(40m)和限制降深(止采)值(70m)，并进行了地面沉降发展趋势预测。文中提出以调控地下水位为主，避让和工程措施相结合的防治对策，以期对沧州市地面沉降防灾减灾工作有所促进和帮助。 相似文献
10.
In terms of controlling groundwater in deep foundation pit projects, the usual methods include increasing the curtain depth, reducing the amount of pumped groundwater, and implementing integrated control, in order to reduce the drawdown and land subsidence outside pits. In dewatering design for confined water, factors including drawdown requirements, the thickness of aquifers, the depth of dewatering wells and the depth of cutoff curtains have to be considered comprehensively and numerical simulations are generally conducted for calculation and analysis. Longyang Road Station on Shanghai Metro Line 18 is taken as the case study subject in this paper, a groundwater seepage model is developed according to the on-site engineering geological conditions and hydrogeological conditions, the excavation depth of the foundation pit as well as the design depth of the enclosure, hydrogeological parameters are determined via the pumping test, and the foundation pit dewatering is simulated by means of the three-dimensional finite difference method, which produces numerical results that consistent with real monitoring data as to the groundwater table. Besides, the drawdown and the land subsidence both inside and outside the pit caused by foundation pit dewatering are calculated and analyzed for various curtain depths. This study reveals that the drawdown and the land subsidence change faster near the curtain with the increase in the curtain depth, and the gradient of drawdown and land subsidence changes dwindles beyond certain depths. In this project, the curtain depth of 47/49 m is adopted, and a drawdown-land subsidence verification test is completed given hanging curtains before the excavation. The result turns out that the real measurements basically match the calculation results from the numerical simulation, and by increasing the depth of curtains, the land subsidence resulting from dewatering is effectively controlled. 相似文献
11.
In terms of controlling groundwater in deep foundation pit projects, the usual methods include increasing the curtain depth, reducing the amount of pumped groundwater, and implementing integrated control, in order to reduce the drawdown and land subsidence outside pits. In dewatering design for confined water, factors including drawdown requirements, the thickness of aquifers, the depth of dewatering wells and the depth of cutoff curtains have to be considered comprehensively and numerical simulations are generally conducted for calculation and analysis. Longyang Road Station on Shanghai Metro Line 18 is taken as the case study subject in this paper, a groundwater seepage model is developed according to the on-site engineering geological conditions and hydrogeological conditions, the excavation depth of the foundation pit as well as the design depth of the enclosure, hydrogeological parameters are determined via the pumping test, and the foundation pit dewatering is simulated by means of the three-dimensional finite difference method, which produces numerical results that consistent with real monitoring data as to the groundwater table. Besides, the drawdown and the land subsidence both inside and outside the pit caused by foundation pit dewatering are calculated and analyzed for various curtain depths. This study reveals that the drawdown and the land subsidence change faster near the curtain with the increase in the curtain depth, and the gradient of drawdown and land subsidence changes dwindles beyond certain depths. In this project, the curtain depth of 47/49 m is adopted, and a drawdown-land subsidence verification test is completed given hanging curtains before the excavation. The result turns out that the real measurements basically match the calculation results from the numerical simulation, and by increasing the depth of curtains, the land subsidence resulting from dewatering is effectively controlled. 相似文献
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Characterization of land subsidence induced by groundwater withdrawals in Su-Xi-Chang area, China 总被引：5，自引：0，他引：5
Xiao-Qing Shi Yu-Qun Xue Shu-Jun Ye Ji-Chun Wu Yun Zhang Jun Yu 《Environmental Geology》2007,52(1):27-40
Su-Xi-Chang area is one of the typical regions in China which suffers from severe land subsidence. Various tools of field
monitoring were integrated to study the characteristics and mechanisms of land subsidence in this region. The occurrence and
the development of the land subsidence in this region are strongly related to the groundwater pumping both in time and space.
The main consolidation layers are the soft mud layers; however, the compressibility of the confined sandy layers should not
be ignored. The second and third confined aquifers contributed more than 30% of total subsidence. Meanwhile, irrecoverable
deformations were also observed in the sandy layers. Different sandy layers deform diversely under different stress conditions.
Some have the elastic feature. But the soil strata, including both sandy layers and clayey layers, located in the center of
the groundwater level depression cone exhibited obvious viscous mechanical behavior which caused the common lag phenomenon.
The sand composition (mingled with small clay particles or interbeds) and sand rheology are the two main reasons for the lag
phenomena in sandy layers. A series of laboratory tests for modeling the effective stress changes due to groundwater withdrawals,
were conducted to investigate the mechanism of the lag phenomenon. Based on the test results, the relationship of stress–strain–time
for saturated sands is obtained; and it could be expressed as power functions. The results also showed that the compression
of the sandy layers was time dependent, and its deformation could be remarkable. When establishing land subsidence model,
the deformation for the similar soil formation could be elastic, visco-elastic and even visco-elastic–plastic, because of
the different groundwater level fluctuation experienced. 相似文献
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开采条件下山东德州深层水资源组成及其与地面沉降的关系 总被引：1，自引：1，他引：0
针对德州长期过量开采深层水导致地下水位不断下降、地面沉降等环境地质问题,以深层地下水动态、地面沉降监测及其对应的粘性地层为主要研究对象,应用水文地球化学、地下水动力学和同位素技术方法,初步查明深层水主要形成于末次冰期盛期的大气降水补给;考虑地面沉降条件下,开采资源中20.6%的侧向径流补给和越流补给来自区域径流系统,反映深层地下水具有一定的更新能力;含水层弹性释水占17.5%,其中61.9%来自粘性土的压密释水,这是产生地面沉降的直接原因。 相似文献
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Mauro Giudici Stefano Margiotta Fiorella Mazzone Sergio Negri Chiara Vassena 《Environmental Earth Sciences》2012,67(7):1891-1907
The control exerted by the hydrostratigraphic structure on aquifer recharge, groundwater flow and discharge along the coastal areas of a Mediterranean basin (Salento peninsula, about 5,000?km2 wide, southern Italy) is assessed through the development and application of a groundwater flow model based on the reconstruction of the hydrostratigraphic architecture at the regional scale. The hydrostratigraphic model, obtained by processing surface and subsurface data, is applied to map the top of the main aquifer, which is hosted in the deep hydrostratigraphic unit corresponding to Cretaceous and Oligocene limestones with complex geometrical relationships with the sea. It is also used to estimate the aquifer recharge, which occurs by percolation through overlying younger sediments with low permeability. These data are completed with information about the soil use to estimate water abstraction for irrigation and with literature data to estimate the water abstraction for drinking and industrial purposes. The above-sketched conceptual model is the basis for a finite difference groundwater 2D pseudo-stationary flow model, which assumes the following fundamental approximations: the fractured and karst limestone hydrostratigraphic unit can be approximated, at the model scale, as a continuous medium for which the discrete Darcy??s law is valid; the transition zone between salt and fresh water is so small with respect to the grid spacing that the Ghyben?CHerzberg??s approximation for a sharp interface can be applied. Along the coastline different boundary conditions are assigned if the top of the limestone hydrostratigraphic unit lies either above the sea level (the aquifer has a free surface and fresh water is drained), or below the sea level (the aquifer is under pressure and the contact with sea occurs off-shore). The groundwater flow model correctly predicts the areas where the aquifer is fully saturated with salt water. 相似文献
15.
Ground subsidence,Quaternary faults and vulnerability of utilities and transportation networks in Thessaly,Greece 总被引：1，自引：0，他引：1
Ground fissures and subsidence have caused extensive damage in structures and the utility networks (roads, railroad line,
Larisa NATO airport, telecommunication network) in the plain of Thessaly, central Greece, in the last 20 years. The fact that
these fissures are parallel to Quaternary faults controlling the structural evolution of the Thessaly basin, marked by intense
recent seismic activity, led some scientists to regard them as manifestation of tectonic creep, even premonitory phenomena
of major future seismic events. A careful study of the geometric characteristics and of the kinematics of these ground fissures,
however, revealed that they only reflect shear failure of the ground due to compaction of loose sediments following significant
decline of the groundwater level due to over-pumping; i.e. a geotechnical and not a tectonic process. Furthermore, theoretical
considerations and modeling predict surface fissuring along zones of anomalous basement, normal-fault controlled topography.
This explains the correlation between ground fissures and active Quaternary normal faults. 相似文献
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济宁市地下水与地面沉降三维有限元模拟 总被引：1，自引：0，他引：1
在分析济宁市水文地质条件的基础上 ,对引起地面沉降诸因素进行了分析 ,并建立了地面沉降量与地下水位变幅之间的相关关系。集中过量开采地下水是引起济宁市地面沉降的主要原因。在此基础上 ,建立了准三维地下水流模型和一维地面沉降模型。通过水力联系建立地下水与地面沉降耦合数值模型 ,运用有限元法对地下水渗流场和地面沉降量进行模拟 ,并对 2 0 0 0年和 2 0 10年地面沉降进行了预测 相似文献
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通过地球物理勘探和地下水动态研究,认为柏乡地裂缝主要是过量开采地下水引起的。过量开采地下水导致了该地区大面积的地面沉降,地层的差异沉降诱发了地裂缝;大量降水造成表层土软化,有些表层土随雨水流入下面的裂缝中,使地裂缝显现出来。 相似文献
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衡水地区地裂缝空间发育特征与地下水位降深关系 总被引：1，自引：0，他引：1
通过浅层地震法及高密度电阻率法物探对河北衡水地区最近发现的3条地裂缝调查,探明了地裂缝地下发育深度、宽度、倾向等,发现地裂缝在地表与地下发育特征有明显不同：地表以一条地裂缝存在,在地下深处则以裂缝带发育,裂缝带两侧裂缝埋深不同,地下裂缝形态表现为上窄下宽。对该地区深层钻探、水文地质和多年地下水开采等资料分析表明,该地区的地裂缝是地质历史时期地质构造活动产物,开采深层地下水等资源则是促使地裂缝发展的主要原因。通过对不同地点地裂缝发育深度与近36年以来地下水水位降深的关系分析,结果显示：不同地区地裂缝发育深度与相应深层地下水水位降深呈线性关系。研究成果对地裂缝机理研究及预防开采深层地下水对地质环境的影响具有指导作用。 相似文献
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Excessive groundwater withdrawal and resultant land subsidence in the Su-Xi-Chang area,China 总被引：5，自引：1，他引：4
Yun Zhang Yu-Qun Xue Ji-Chun Wu Xiao-Qing Shi Jun Yu 《Environmental Earth Sciences》2010,61(6):1135-1143
Excessive groundwater withdrawal has caused severe land subsidence in the Su-Xi-Chang (SXC) area, China. The restriction and
prohibition on groundwater pumping have been carried out since the late 1990s. Based on the latest updated field data, the
changing pattern of groundwater level and the distribution of land subsidence are analyzed. The distribution of land subsidence
in SXC is closely related to that of the cone of depression in the second confined aquifer in time and space. But land subsidence
is not in synchronization with the changing groundwater level. Both aquitards and aquifers compacted continuously in the early
period of groundwater level rising and behaved as creep materials. A series of laboratory tests were conducted on aquifer
sands, which indicated that the creep deformation under virgin compression is much greater than that under recompression and
unloading, and that the creep of sands decreases rapidly with the cycles of repeating load. The test results reveal the mechanism
of sand creep under the condition of long-term groundwater pumpage. As a consequence of the restriction and prohibition on
groundwater pumping, groundwater level has obviously recovered in the vast majority of the SXC area, and land subsidence has
slowed down and even a little rebound has occurred in some sites in Suzhou and Changzhou. If the pumpage is strictly limited
continuously, the groundwater level will not decline below the historical lowest value but fluctuate within a certain range.
In such a case, land subsidence in SXC will no longer develop obviously. 相似文献