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1.
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
2.
2018年雨季期间,东非裂谷肯尼亚段地表突然出现一条7~8 km长的巨大地裂缝,该裂缝直接导致连接肯尼亚东西区域的主干道B3公路的毁坏(以下称为B3地裂缝),而作为我国“一带一路”倡议的重点项目“内罗毕至马拉巴标准轨铁路”仅距离该裂缝几公里,科学解释地裂缝的形成机理是铁路工程设施安全运营的重要保障。本文对该地裂缝的空间展布和形成机理进行研究,利用遥感影像详细解译了地裂缝空间位置,通过无人机航拍测绘建立了裂缝带高分辨率数值高程模型,在此基础上详细测量了地裂缝两侧地表垂向位移、地裂缝宽度和深度等指标。通过野外调查发现地裂缝发育在裂谷东边界F4活动断层之上,其空间位置受F4断层控制,地裂缝垂向剖面显示全新世沉积物有明显断错,且有多条破裂结构面贯穿其中:地裂缝下部火山碎屑岩层有明显拉张裂隙,这成为雨季期间地表水垂向下渗的通道,使浅表部松散沉积物向下运移。同时,裂谷区发育的南北向断层系统是雨季期间地下水横向流动的主要通道,这些过程导致地下水径流在雨季期间会不断潜蚀下部的土层,致使地表物质不断向下搬运,从而造成地表大规模开裂和塌陷,形成裂谷区受活动断层空间分布控制的构造型地裂缝。 相似文献
3.
Jianwei Qiao Jianbing Peng Yahong Deng Yanqiu Leng Zhenjiang Meng 《Journal of Earth System Science》2018,127(1):10
Qinglong Graben is located in southeastern Yuncheng Basin, China flanked by two north-east trending normal faults, where the geological condition is favourable for generating earth fissures. Since 1978, five earth fissures have formed in Qinglong Gaben. In the present work, a series of geological investigation consisting of site investigation, geological drilling and trench excavation was used to characterise and determine the reasons for the formation of the earth fissures. The site investigation indicated that the trend of the five earth fissures are parallel to the general strike of the normal fault, i.e., geological drilling and trench studies revealed that syn-sedimentary fault is the key reason for the formation of the earth fissures. Additionally, over-exploitation of groundwater and erosion process are important factors in the development and expansion of the earth fissures in Qinglong Graben. The earth fissures forming process in Qinglong Graben can be divided into three stages: the regional extension first caused normal faults under the surface, and then the pumping action of excessive groundwater induced the normal faults propagate to the surface, and finally the erosion promoted the formation of the current earth fissure. 相似文献
4.
Excessive groundwater withdrawal from an aquifer system leads to three-dimensional displacement, causing changes in the states of stress and strain. Often, land subsidence and sometimes earth fissures ensue. Field investigation indicates that land subsidence and earth fissures in Wuxi, a city in eastern China, are mainly due to excessive groundwater withdrawal, and that they are temporally and spatially related to groundwater pumping. Groundwater withdrawal may cause tensile strain to develop in aquifer systems, but tensile strain does not definitely mean tensile stress. Where earth fissures are concerned, the stress state should be adopted in numerical simulations instead of the strain state and displacement. The numerical simulation undertaken for the Wuxi area shows that the zone of tensile strain occupies a large area on the ground surface; nevertheless, the zone of tensile stress is very limited. The zone of tensile stress often occurs near the ground surface, beneath which the depth to the bedrock surface is relatively small and has considerable variability. Earth fissures often initiate near the ground surface where tensile stress occurs. Tensile stress and earth fissures rarely develop at the centers of land subsidence bowls, where compressive stress is dominant. 相似文献
5.
Jianbing Peng Lingchao Meng Quanzhong Lu Yahong Deng Zhenjiang Meng 《Environmental Earth Sciences》2018,77(11):407
Since the 1980s, increasing human activity and continuing over-exploitation of groundwater resources have caused the earth fissures in the rift basin in Shanxi, China, to enter an active phase. Buildings along these earth fissures have been seriously damaged. Four massive earth fissures that developed in the Taigu and Qixian areas of the eastern Taiyuan basin endanger the operational safety of the high-speed railway that passes through this region. Using field observations, measurements, and exploration, we determined that the four earth fissures are parallel to each other, have a northeast trend, and are separated by approximately equal distances. The rupture zones of these earth fissures are generally 10–50 m wide and are formed by the main fissures and secondary fissures. The width of the zone affected by the earth fissures is 20–50 m based on deformation and the damage done to buildings. These fissures formed on the Earth’s surface; their hanging walls are lower than their foot walls, forming normal faults; and the ground surface around the fissures exhibits ridges and depressions. The fissures are connected to deep hidden faults. The fault displacement increases with increasing depth, which is characteristic of syn-sedimentary faults. These earth fissures are characterized by vertical displacement, and their average annual activity rate is 1–3 cm. We believe that the formation of this large-scale fissure group may be related to the tectonic structure of the hidden faults in the basin and may also be affected by the continuous regional extensional stress of the basin. The current increased level of activity could be caused by the over-exploitation of groundwater in the area. 相似文献
6.
In the Bicholime, Goa, there is an iron-ore mine surrounded by villages and small towns. Exploitation of such an enormous amount of iron ore may disturb the local groundwater table, thereby causing groundwater depletion. However, these effects are dependent mainly on the geological formations in the region and the mining method. The effects of Bicholime mining on the surrounding groundwater resources and subsurface strata conditions are the main objective of this study. For this purpose, ground penetrating radar surveys were carried out to study the possible effects of mining on the hydrological regime of this open-pit mine, and the subsurface conditions in the Bicholime opencast iron-ore mine, Goa. The results of these surveys show that laterite layers exist from the surface to depths varying from 5 to 22 m at all study locations in the mining area, and in most places clay layers exist, except for the GPR section along the profiles DD1 and EE1 in the village at depths of 8-22 m. Due to the presence of impervious clay layers, mining and dewatering in the leasehold areas will most likely not affect the surrounding hydrological regime of this mining area. It is concluded that no hydrological connection exists between the open pits and the surrounding villages, so that sufficient groundwater is available in the village area, in spite of the enormous extraction of iron ore from the underground. 相似文献
7.
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
8.
地裂缝是临汾盆地主要的地质灾害之一, 自20世纪70年代盆地开始出现地裂缝以来, 至2012年8月共发现86条地裂缝。本文以临汾盆地内部典型地裂缝临汾果场地裂缝为研究对象, 详细地论述了地裂缝发育的地质环境背景。利用野外调查、测量、槽探、钻探和物理勘探等地质手段, 主要研究了地裂缝的发育特征, 包括平面特征、灾害特征、浅部剖面结构特征和深部特征4个方面, 总结了地裂缝的活动规律。发现果场地裂缝平面延伸长, 宽度大, 走向稳定, 灾害严重; 浅表层上宽下窄, 呈喇叭状, 深部结构显示地裂缝下伏隐伏断层, 地裂缝活动受降雨控制。通过分析影响地裂缝形成的各个因素:盆地构造、超采地下水和强降雨, 将果场地裂缝的形成分为3个阶段:孕育阶段、出露阶段和扩展阶段; 最后概化了果场地裂缝的成因机理:构造孕缝、抽水诱缝和降雨扩缝。 相似文献
9.
近几十年来,国内外学者对地下水开采引起的地裂缝问题进行了大量的研究,取得了许多丰硕的科研成果。总体来说,在地裂缝的成因机制方面学界尚未形成一个统一的观点;在地裂缝数值模拟方面,由仅考虑土体一维垂向变形发展到同时考虑土体垂向和水平向变形、地下水流模型和土体变形模型由不耦合发展到流固耦合,对开采地下水条件下土体变形的本构关系由弹性发展到弹塑性、粘弹塑性,特别是在地裂缝形成的判别准则方面由过去的定性判别发展到半定量判别。由于地裂缝问题本身的复杂性,目前的研究还远不够成熟,仍有许多问题需要解决。 相似文献
10.
过量开采地下水诱发的地裂缝("采水型"地裂缝)灾害对社会造成严重损失,受到人们普遍关注。近几十年来,国内外学者对其成因机制进行了大量研究,取得了丰硕成果。本文系统分析了前人的研究成果,归纳出"采水型"地裂缝的差异沉降成因、拉张性水平应变成因和四种成因模式;然后针对中国三个典型的"采水型"地裂缝发育区,即汾渭盆地、华北平原、苏锡常地区,阐述了各地地裂缝分布、发育特征和成因机理,并选择典型地段地裂缝进行成因分析,认为汾渭盆地和华北平原地区部分地裂缝属于"先期断层模式",而苏锡常地区地裂缝总体属于"基岩起伏模式",并阐述了该模式下导致地裂缝发育的差异性变形、水平应变作用机理。 相似文献
11.
Based on the formation and development analysis of the environmental geological disaster of land subsidence, earth fissures and other geological disasters in the North China, it showed these disasters caused a very serious problem in some areas of the North China, such as the deep groundwater exploitation cone, which is accumulated with great damage and loss and is hard to be controlled, therefore, great attention should be paid. It is considered that the formation of the deep groundwater cone is the root of various geological environmental problems, and the groundwater cone recovery is the key to solve other environmental problems 相似文献
12.
Ground cracks in Ethiopian Rift Valley: facts and uncertainties 总被引：2，自引：0，他引：2
No accurate relationship has been obtained in this study between ground cracks in Ethiopian Rift Valley and the most common causes of earth fissures such as aquifer-system compaction and increased horizontal seepage stresses. This is due to the fact that the level of groundwater withdrawal responsible for these processes is still negligible in Ethiopia. If aquifer-system compaction and increased horizontal seepage stresses have a certain role, then it should be through the long-term effect of groundwater flow from basins to neighboring lakes. The ground cracks appeared also not to have a direct link with active faulting or distant earthquakes. Structurally, the Ethiopian Rift Valley is dominated by NE–SW-trending tensional faults, but no evidence is obtained in this study to associate the process of surface cracking with major tectonics. However, an aseismic elastic strain, which originates at depth and propagates upward through sediments without the formation of bedrock faults, could result in conditions conducive to the development of cracks. Then, fissures might ultimately be created after heavy rainfalls by near-surface processes such as piping and hydrocompaction along water-line sources. 相似文献
13.
河北平原地裂缝分布特征及成因机制研究 总被引：14，自引：8，他引：14
河北平原是地裂缝地质灾害较发育的地区。通过河北平原地裂缝地质灾害时空分布规律研究,对河北平原地裂缝形成的主要因素及成因机制进行了研究。河北平原地裂缝主要分布在山前冲洪积扇裙区,发育在全新世地层中。地裂缝地质灾害平面形态上可分为直线型、雁列型、锯齿型、折线型和弯曲形。地裂缝地质灾害空间分布上有方向性、群集性和系统性。河北平原地裂缝分布范围呈逐渐扩大的趋势;分布区域从时间上呈逐渐由南向北扩展之势。河北平原从时间上地裂缝发育条数和发育长度随时间各有不同特点。导致河北平原地裂缝发生的主要因素有地震构造、地下水超采和地面塌陷。 相似文献
14.
Earth fissures in Jiangsu Province,China and geological investigation of Hetang earth fissure 总被引：1，自引：0，他引：1
Earth fissures are a geohazard in Jiangsu Province, China. They can be caused by earthquakes and active faults, underground
mining, groundwater extraction and landslides. In order to establish a provincial rehabilitation plan in Jiangsu, a range
of monitoring programs, surveys, geological investigations and modeling have been implemented or planned. One of the focuses
of the project is the land subsidence and earth fissures caused by excessive groundwater withdrawal in Suzhou, Wuxi and Changzhou
(Su-Xi-Chang) area, southern Jiangsu Province. Hetang earth fissure within the Su-Xi-Chang area was first reported in 1995
and a series of investigation has been conducted since then. The site investigations and geophysical survey in 1997 have recognized
the causative factor as the excessive groundwater drawdown coupled by the underlying bedrock ridge. An open trench excavation
in 2007 and a plane strain analysis suggest that Hetang earth fissures may have cracked from the bedrock ridge to ground surface.
Geological drilling in 2007 has further confirmed the existence and configuration of the ridge and extracted soil samples
for laboratory tests to obtain soil parameters for numerical analyses and modeling of land subsidence and earth fissures in
the Su-Xi-Chang area, Jiangsu, China. The laboratory tests are currently in progress and the result of numerical analyses
and modeling is expected to be presented in the near future. 相似文献
15.
在调查和监测中发现北京平原区地裂缝受灾体灾害表现形式不同,具有显著的区域特点。为揭示其形成过程,指导地裂缝防治工作,本文以宋庄地裂缝、高丽营地裂缝两处典型地裂缝作为靶区,从受灾体、剖面、深度、活动四方面揭示两处地裂缝形态特征,分析不同因素对二者差异化形态特征塑造的影响。结果显示:（1）宋庄地裂缝受灾体表现出明显的拉张变形,剖面上地裂缝上宽下窄铅直纵向延伸,深部未与隐伏断裂重接复合;高丽营地裂缝受灾体表现为显著的垂向错动及剪切破坏,剖面上地裂缝曲折纵向延伸,错开上下两盘地层,深部与隐伏断裂重接复合。（2）地震及区域应力场对两处地裂缝的水平形态特征进行塑造;地下水超采引发的土体差异性水平运动形成的拉应力作用于宋庄地裂缝,并对宋庄地裂缝形态进行再次塑造;高丽营地裂缝继承了黄庄—高丽营断裂形态特征;小区域差异沉降对垂向形态特征进行再次塑造。（3）宋庄地裂缝发育主要受地下水开采影响,对此类地裂缝防治应实施地下水减采、压采限采等方式,高丽营地裂缝发育受地下水开采及隐伏断裂双重影响。对此类地裂缝的防治除控制水位下降外,还需实时监测隐伏断裂活动情况,建立有效的预警预报体系。 相似文献
16.
Earth fissures triggered by groundwater withdrawal and coupled by geological structures in Jiangsu Province,China 总被引：3，自引：0，他引：3
Earth fissures in Jiangsu Province, China have caused serious damages to properties, farmlands, and infrastructures and adversely
affected the local or regional economic development. Under the geological and environmental background in Jiangsu Province,
this paper presents the earth fissures caused by excessive groundwater withdrawal and coupled by distinctive geological structures
such as Ancient Yellow River Fault in Xuzhou karst area, and Ancient Yangtze River Course and bedrock hills in Suzhou, Wuxi,
and Changzhou area. Although all the earth fissures are triggered by groundwater exploitation, the characteristics are strongly
affected by the specific geological and hydrogeological settings. In particular, in the water-thirsty Xuzhou city, the cone
of depression caused by groundwater extraction enlarged nearly 20 times and the piezometric head of groundwater declined 17 m
over a decade. As groundwater is extracted from the shallowly buried karst strata in the Ancient Yellow River Fault zone,
the development of earth fissures is highly associated with the development of karstic cavities and sinkholes and their distribution
is controlled by the Ancient Yellow River Fault with all the 17 sinkholes on the fault. On the other hand, in the rapidly
developing Southern Jiangsu Province, groundwater is mainly pumped from the second confined aquifer in the Quaternary, which
is distributed neither homogeneously nor isotropically. The second confined aquifer comprises more than 50 m thick sand over
the Ancient Yangtze River Course, but this layer may completely miss on the riverbank and bedrock hills. With a typical drawdown
rate of 4–6 m per annum, the piezometric head of groundwater in the second confined aquifer has declined 76 m at Maocunyuan
since 1970s and 40 m at Changjing since mid-1980s, and a large land subsidence, e.g., 1,100 mm at Maocunyuan, is triggered.
Coupled with the dramatic change of the bedrock topography that was revealed through traditional geological drilling and modern
seismic reflection methods, the geological-structure-controlled differential settlement and earth fissures are phenomenal
in this area. 相似文献
17.
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
18.
简述了临潼—长安断裂带的特征及与地裂缝的关系,根据临潼—长安断裂带内两场地地层勘探剖面,证实了临潼—长安断裂带内地裂缝的存在,表明其与发育在临潼—长安断裂带上盘的西安地裂缝具有相同的性质和特征。同时通过地裂缝两侧地层的错断及厚度变化分析了地裂缝的特点及其地质历史活动规律,表明临潼—长安断裂带内的地裂缝活动受断裂活动影响也表现为东强西弱的特征。 相似文献
19.
Groundwater abstraction and contamination in Lithuania as geoindicators of environmental change 总被引：1，自引：0，他引：1
Groundwater abstraction not only affects subsurface water, but also causes changes in the hydrosphere, lithosphere, and biosphere. There are certain symptoms of these environmental changes that might be designated as geoindicators. Geoindicators related to groundwater abstraction and contamination in Lithuania have been classified into three groups related to: (1) the decline/rise of groundwater levels, (2) the deterioration of groundwater quality, and (3) the intensification of water-rock interaction. On the basis of hydrogeological and hydrological investigations carried out over many years, different environmental impacts of intensive groundwater use are demonstrated. The most important among them are the formation of depression cones, intensification of groundwater pollution, saltwater encroachment, and the intensification of karst. 相似文献
20.
G. Y. Wang Greg Guanlin You B. Shi S. L. Wu J. Q. Wu 《Environmental Earth Sciences》2010,61(5):1085-1093
Jiangyin County is in the infamous Su–Xi–Chang land subsidence area caused by excessive groundwater withdrawal in Jiangsu
province, China. The maximum accumulated land subsidence reached 1,310 mm near the centre of the subsiding trough in 2006
in southern Jiangyin, and earth fissures of significant vertical offsets have been observed at Changjing, Hetang and Wenlin
which form an arc towards the subsidence trough. An ancient Yangtze River course is found underlying and passing through the
depression in southern Jiangyin, forming a local basin surrounded by outcropped bedrock ridges in the north and south. The
Quaternary stratigraphy demonstrates significant heterogeneities in the basin; the second confined aquifer is much thicker
and deeper and encapsulated inside the basin and absent above the ridges. The development of earth fissures along the Changjing–Hetang–Wenlin
arc might be a combination of an inward rotation of sediments due to a large differential subsidence, an inward movement driven
by seepage force and a steeper slope along the south-eastern shoulder of the basin that facilitates the development of horizontal
tensile strain and/or shear strain necessary for fissuring. The land subsidence has slowed down and no new earth fissure zone
has occurred in the area after the banning of deep groundwater extraction was enacted in 2001. 相似文献