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南宁市是广西岩溶地面塌陷危害十分严重的城市之一。2012年6月2日突发的岩溶地面塌陷主要集中分布在坛洛镇南西方向,形成塌陷坑19个,地裂缝17条,威胁62户共232人,潜在经济损失约870万元。坛洛塌陷多形成于松散盖层厚度小于15 m,地下水位埋深小于20 m,地下岩溶强发育的区段。碳酸盐岩岩溶发育、松散盖层厚度较小和水动力条件（降水、地表水和地下水）复杂为岩溶塌陷产生的必要条件,尤以地下水的作用对岩溶塌陷的形成起至关重要的作用。通过对坛洛地下水动态观测与岩溶塌陷的调查研究确定地下水强径流带,分析评价岩溶地面塌陷的危险性,为岩溶地区的岩溶塌陷危险性勘察、评价工作提供一定指导意义。 相似文献
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唐山黄庄岩溶塌陷形成条件和机理分析 总被引：4，自引：3，他引：1
为查明唐山黄庄岩溶塌陷形成地质条件与机理,文章从该区岩溶塌陷的地质、地层岩性、水文地质特征对岩溶塌陷的影响等方面入手,研究岩溶地面塌陷的成因诱发条件,利用综合物探方法、钻探及地下水长期观测等技术手段,采用二维高密度测网数据,进行三维高密度数据处理和三维结果多角度分析,研究岩溶塌陷区地下三维空间分布形态、水流运移通道和基岩分布等。研究区岩溶地面塌陷应属于渗透潜蚀作用,塌陷坑分布于地下水的降落漏斗范围内和流水通道区域,特别集中于地下水主要径流方向和水交替强烈的地下水联系密切地段,雨季水气压力变化极为频繁、剧烈,加剧了土洞形成。 相似文献
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铜陵市朝山地区岩溶塌陷形成条件与地面稳定性评价分析 总被引：1，自引：0，他引：1
铜陵市朝山地区岩溶塌陷灾害是安徽省大型地质灾害隐患点。从该区基岩岩性、覆盖层特征、水文地质条件和人为影响等方面入手,利用钻探和地下水长期观测等技术手段,通过岩溶塌陷的影响因素分析,查明了研究区岩溶塌陷形成条件,评价了地面稳定性。得到主要结论如下:区内岩溶塌陷的分布受断裂控制,90%以上的塌坑位于距断裂20 m区域内;区内岩溶塌陷的发生与基岩岩性密切相关,CaO含量高有利于塌陷的发生;区内塌陷多发生于多元或二元结构地层区域;矿山排水是区内岩溶塌陷的主要诱发因素。最后在查明区内岩溶塌陷形成条件的基础上,采用经验指标法对朝山地区地面稳定性进行评价分析,确定研究区为易塌陷区,须重点监测与防治。 相似文献
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通过岩溶工程地质剖面和地质钻孔资料对岩溶发育特征与强度、第四系覆盖层厚度及物质组成、地下水动力条件等进行分析;并以此为基础,根据莲花县城区岩溶塌陷形成特点,结合岩溶塌陷点发生时的降雨量和地下水位变化记录等资料进行综合研究。结果表明:莲花县城区岩溶塌陷主要以水流潜蚀、高压气蚀、负压吸蚀、下渗旋吸、土体软化、重力加载等破坏作用叠加效应形成的土洞型塌陷为主;地下水位循环交替是引发岩溶塌陷的主要原因,而降雨强弱又直接影响着地下水动态变化;地下水循环交替不同阶段表现出对盖层的各类破坏作用的特征不同,一般在经多期次地下水循环交替过程后形成地面塌陷;部分地面塌陷因农田囤水、地面加载或振动而诱发。该文研究成果可为莲花县岩溶塌陷预警预报及防治提供科学依据,其他南方岩溶发育相近地区具有参考意义。 相似文献
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以唐山市岩溶地面塌陷区为依托，提出了单因子图迭置分析的岩溶地面塌陷危险区划分原则和方法，编制了相应的软件系统ＫＬＣ，并对唐山市城市岩溶塌陷进行了综合分区评价。以此为基础对岩溶塌陷宏观减灾对策进行了探讨。提出了以防止岩溶塌陷为目的的地下水优化管理方案，使地下水状态在岩溶地面塌陷危险区形成最不利于塌陷产生的水动力状态，以实现全区塌陷危害最小的目的。 相似文献
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金沙洲可溶性灰岩分布面积广,岩溶洞隙发育,洞隙及地下水的连通性强,上覆第四系松散土体中软土广泛分布,客观存在岩溶地面塌陷及地面沉降的地质环境条件。2007年4月起,受某高铁隧道施工抽排地下水的影响,金沙洲地下水出现异常波动,引发了地面塌陷及地面沉降。文章根据监测数据,经对比分析结果表明,区内岩溶地面塌陷及地面沉降受控于地下水位的变化,地下水位波动至基岩面附近时,是地面塌陷较活跃的时期,地面沉降与地下水位变化呈正向相关。文章进一步对地面沉降与地下水位变化关系的机理进行了探讨,认为目前地下水位尚未恢复正常的区域仍存在地面塌陷及地面沉降的隐患。 相似文献
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通过对松宜矿区地面塌陷调查研究,按煤层顶板埋深和塌陷成因的不同将其分为浅埋型采空塌陷和深埋型岩溶塌陷,前者系指煤层顶板为栖霞组、茅口组地层区域,在缓坡地带、构造、岩溶发育部位、煤层厚度大的采空区易形成采空塌陷,无序复采、矿柱遭受破坏是主要诱发因素;后者是在矿坑高强度疏排地下水导致地下水位大幅降低,形成以真空吸蚀为主要成因的岩溶塌陷。针对其成因机制,提出了防治建议,对矿区地质环境综合治理具有实际意义。 相似文献
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广州花都区赤坭镇岩溶地面塌陷地质灾害现状及防治对策 总被引：1，自引：0，他引：1
自20世纪90年代未以来,由于人类工程活动的加剧,广州市花都区赤坭镇一带多次出现严重的岩溶地面塌陷活动。本文依据实地岩溶地面塌陷地质灾害勘查资料,系统分析了赤坭镇岩溶地面塌陷的分布、规模和危害程度;研究结果表明,赤坭镇岩溶地面塌陷的形成原因主要是人工开挖形成负地形采石场和过量抽排地下水造成。在此基础上,针对赤坭镇岩溶地面塌陷的实际情况,提出了岩溶地面塌陷地质灾害的防治对策。 相似文献
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新集矿区松散层工程地质特征及地面沉降预测 总被引：1，自引：1，他引：0
为了有效地防治新集矿区地面沉降,研究了该区第四系松散层的工程地质特征与地面沉降的关系:松散层的大部分力学参数在地表以下30m内变化不大,埋深大于30m后变化明显;粘性土的压缩性明显大于砂性土;粘土中伊利石含量高,排水条件好,压缩性好。将松散层划分为3个主要压缩层;建立了地面沉降计算模型,预测区内地面沉降为0.2832~0.8293m。 相似文献
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三山岛金矿海边地下开采矿山稳定性的数值模拟分析 总被引：1，自引：0，他引：1
本文用数值模拟的分析方法, 评价了三山岛金矿地下开采引起的开采效应及地表下沉盆地的变形特征。结果表明, 矿山地表是稳定的, 上部一期工程开采引起的地表最大下沉量不超过700mm, 深部开挖时不超过995mm左右；在采场充填的情况下, 地表下沉值将降低55%左右；由于矿山地表变形较小, 加之覆盖层第四纪中存在着两层总厚度8～12m的隔水粘水层, 因此不致沟通地表水与井下的直接联系而危及矿山的安全。 相似文献
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温岭市西部平原地面沉降特征及防治对策 总被引：1，自引：0，他引：1
温岭市西部平原是经济活动最为活跃的地区．近20年以来，随着地下水开采量的不断增大，引发了严重的地面沉降，本文通过对不同时期的地形高程对比，分析确定了地面沉降量等特征，研究表明温岭市西部平原始地面高程仅2．5～3．3m，近20年来累计最大沉降量已大于1300mm.已成为浙江省地面沉降最为严重的地区之一，地面沉降导致沉降区内部分民房和耕地被水淹，直接影响到当地群众的生活和生产，本文根据温岭市实际，提出了地面沉降的防治措施和对策。 相似文献
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Brian D. Conway 《Hydrogeology Journal》2016,24(3):649-655
Land subsidence due to groundwater overdraft has been an ongoing problem in south-central and southern Arizona (USA) since the 1940s. The first earth fissure attributed to excessive groundwater withdrawal was discovered in the early 1950s near Picacho. In some areas of the state, groundwater-level declines of more than 150 m have resulted in extensive land subsidence and earth fissuring. Land subsidence in excess of 5.7 m has been documented in both western metropolitan Phoenix and Eloy. The Arizona Department of Water Resources (ADWR) has been monitoring land subsidence since 2002 using interferometric synthetic aperture radar (InSAR) and since 1998 using a global navigation satellite system (GNSS). The ADWR InSAR program has identified more than 25 individual land subsidence features that cover an area of more than 7,300 km2. Using InSAR data in conjunction with groundwater-level datasets, ADWR is able to monitor land subsidence areas as well as identify areas that may require additional monitoring. One area of particular concern is the Willcox groundwater basin in southeastern Arizona, which is the focus of this paper. The area is experiencing rapid groundwater declines, as much as 32.1 m during 2005–2014 (the largest land subsidence rate in Arizona State—up to 12 cm/year), and a large number of earth fissures. The declining groundwater levels in Arizona are a challenge for both future groundwater availability and mitigating land subsidence associated with these declines. ADWR’s InSAR program will continue to be a critical tool for monitoring land subsidence due to excessive groundwater withdrawal. 相似文献
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Monitoring land subsidence in Semarang,Indonesia 总被引：1，自引：0，他引：1
Semarang is one of the biggest cities in Indonesia and nowadays suffering from extended land subsidence, which is due to groundwater
withdrawal, to natural consolidation of alluvium soil and to the load of constructions. Land subsidence causes damages to
infrastructure, buildings, and results in tides moving into low-lying areas. Up to the present, there has been no comprehensive
information about the land subsidence and its monitoring in Semarang. This paper examines digital elevation model (DEM) and
benchmark data in Geographic Information System (GIS) raster operation for the monitoring of the land subsidence in Semarang.
This method will predict and quantify the extent of subsidence in future years. The future land subsidence prediction is generated
from the expected future DEM in GIS environment using ILWIS package. The procedure is useful especially in areas with scarce
data. The resulting maps designate the area of land subsidence that increases rapidly and it is predicted that in 2020, an
area of 27.5 ha will be situated 1.5–2.0 m below sea level. This calculation is based on the assumption that the rate of land
subsidence is linear and no action is taken to protect the area from subsidence. 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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Kenai, located on the west coast of the Kenai Peninsula, Alaska, subsided during the great earthquake of AD 1964. Regional land subsidence is recorded within the estuarine stratigraphy as peat overlain by tidal silt and clay. Reconstructions using quantitative diatom transfer functions estimate co‐seismic subsidence (relative sea‐level rise) between 0.28±0.28 m and 0.70±0.28 m followed by rapid post‐seismic recovery. Stratigraphy records an earlier co‐seismic event as a second peat‐silt couplet, dated to ～1500–1400 cal. yr BP with 1.14±0.28 m subsidence. Two decimetre‐scale relative sea‐level rises are more likely the result of glacio‐isostatic responses to late Holocene and Little Ice Age glacier expansions rather than to co‐seismic subsidence during great earthquakes. Comparison with other sites around Cook Inlet, at Girdwood and Ocean View, helps in constructing regional patterns of land‐level change associated with three great earthquakes, AD 1964, ～950–850 cal. yr BP and ～1500–1400 cal. yr BP. Each earthquake has a different spatial pattern of co‐seismic subsidence which indicates that assessment of seismic hazard in southern Alaska requires an understanding of multiple great earthquakes, not only the most recent. All three earthquakes show a pre‐seismic phase of gradual land subsidence that marked the end of relative land uplift caused by inter‐seismic strain accumulation. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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北京平原区快速发展的地面沉降对高速铁路的发展构成了威胁,地面沉降与过量开采地下水造成的水位下降关系密切,为此有针对性地开展基于高速铁路的地下水动态与地面沉降相关关系研究对于高铁安全运行意义重大,特别是对于制定高铁沿线地下水开采方案、地面沉降减缓措施和工程措施至关重要。基于其对高速铁路的影响模式,本文将地面沉降分为区域沉降和局部沉降两种类型。针对区域沉降,利用Logistic方程,使用天竺、望京及王四营分层地面沉降和地下水位数据,构建了不同层位地下水水位变化与地面沉降之间的相关关系模型,通过ABAQUS计算局部地区,对于6m高路堤和15m CFG桩处理深度的地基而言,当渗透系数k=2m／d,距离线路边缘25m处浅层地下水下降10m将产生约61—85mm的沉降。 相似文献
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地面沉降不但影响到下辽河平原地区的经济生产,而且导致湿地逐年退化,对生态环境产生非常严重的影响.该区域没有监测网络,无法知道具体的沉降范围和大小.为了查清下辽河平原历史地面沉降状况,有效地服务于地方经济发展和环境改善,首次在下辽河平原区域提出了地形图比对方法.通过搜集不同时期地形图,对同一高程点进行比对,结果表明下辽河平原地区围绕着油田集中采油区和地下水集中开采区,存在地面沉降现象,最大沉降量达到3 m.地形图比对有效地解决了下辽河平原无法确定沉降范围和量级的困难,是一种在没有监测网络的情况下,掌握工作区地面沉降情况的良好方法. 相似文献