In recent years, the ground ifssures in the North China Plain have been rapidly deteriorating and are threatening local living conditions and production. This study analyzes the major factors influencing the ground fissure. The main controling factors include the basement structure, the Holocene geological environment and the basement structure creep. Topography, geomorphology, lithology, surface water, ground water, earthquakes, ground surface subsidence, continuous drought, underground karst and human engineering activities are the factors that affect the development of ground ifssures. It is considered that a single factor is not solely responsible for the formation of ground ifssures in North China but rather a combination of related factors. It is signiifcant to study the formation mechanism and hazard control of ground ifssures in the North China Plain.

从20世纪80年代开始至今,河北平原出现了大量地裂缝,致使建筑物和道路交通遭受破坏,给当地人民生命财产带来了严重危害.断层蠕滑型地裂缝因其延伸长、深度大、破坏严重、防治难度大而更应引起重视,断层蠕滑型地裂缝对河北平原地裂缝的研究及防治具有重要意义.笔者在大量野外调查的基础上,从实地调查的800多条地裂缝中选取了两条典型断层蠕滑型地裂缝——隆尧地裂缝、辛-安-深-饶地裂缝,由物探、槽探等综合勘查手段作为验证,初步分析了该类型地裂缝的成因:它们受控于断裂活动,区域内的深部构造活动为地裂缝的形成提供了动力基础.地下水、地表水的活动对地裂缝的地表开启及发展有重要的促进作用.

The ground fissures in Longyao County are the typical surface disaster in North China region.They not only caused eroding,collapsing,extension fracturing,faulting,cracking and other geological disasters on the earth's surface,but also caused severe economic losses in the local agricultural production,engineering construction and the lives of the people.This paper aims to reveal their genetic nature.It is based on geological investigation,monitoring and measuring,trenching,physical exploration.It studies the development characteristics of the Longyao ground fissures.They include the planes,profiles,deep and activity aspects.The paper summarizes the laws of ground fissures.Finally the ground fissure mechanism is analyzed from their crack-pregnant environment,crack-opening conditions and cracking process.the study concludes that:(1)Longyao ground fissures expose in a dozen villages of more than 30km long.They extend towards NWW and NEE which are concordant with the direction of Longyao fault system.Their periodicities are consist of opening,closing,slowly cracking and suddenly cracking periods.(2)Longyao ground fissures are controlled by the faults zone.The conditions such as deep structure,faulted structure and structural landform provide the ground fissures with crack-pregnant environment in the area.The crack-pregnant environment has through three stages: stress accumulation and fractured zone formation.(3)Faulting is the foundation of ground cracking.The groundwater exploitation and surface infiltration also are the important factors.(4)the process of Longyao ground fissures is heterogenous temporally and spatially.From the present investigation and study,the ground fissures are in active period in the area.

Based on the field and trenching survey,an analysis is done on the environmental geology,basic characteristics and formation mechanism of the Zhouzhangzhuang-Dongdianma tectonic cleave.South Longyao Fault causes the latent crack in the surface,which shows up with the erosion of rainfall and irrigation as excessive extraction of groundwater causes lower groundwater level.The measures are to dodge,restrict confined groundwater extraction and strengthen disaster monitoring and pre-warning.

<正>2010年6月1日19时到6月2日6时,玉林市容县和岑溪县接壤地区发生强降雨,降雨历时11个小时,过程降雨量大于300mm。最大降雨量集中在6月2日1时到3时,降雨量达210mm。在强降雨的诱发下,玉林市容县和岑溪县接壤地区约300km2区域范围内暴发群发型滑坡泥石流地质灾害数百处,造成人员伤亡者十余处,造成43人死亡。其中,容县死亡30人,岑溪县死亡13人。基础设施及农林业和房屋受到重大破坏或损毁。

Earth fissures occurs in Hengshui, Baixiang, Wen'an, Anping, Xianghe and Bazhou in Hebei Province in summer and autumn. The earth fissure at Baixiang at Xingtai is as long as 8km. This paper reveals that the Baixiang earth fissure was caused owing to groundwater overdrafts through general combination of geophysical exploration data and ground water level analysis. Over-extraction of groundwater had resulted in large-area land subsidence in this area. The difference in land subsidence occruing at both sides of the former faults finally conduced earth fissure in Baixiang County. At the same time, when superficial earth being intenerated by large amount of meteoric precipitation in Hebei Plain filtered into earth fissure underlying the land surface following the rain water, the Baixiang earth fissure finally emerged on the land surface.

Based on the DRASTIC model,the fuzzy analysis theory and method which are suitable for evaluating aquifer vulnerability are established and have been used in Cangzhou City.The assessing result is consistent with the status of groundwater pollution and reflects the degree of the aquifer's resisting pollution in different areas.

Based on analytical causes of Cangzhou City ground settlement,taking accumulated thickness of cohesive soil layer,mining intensity of underground water,depth of underground water table,geothermal water resources mining,building capacity and accumulated settlement as environmental geological factors for ground settlement hazard evaluation and through fuzzy techniques,calculation of evaluation index and integrated dangerous estimation,this paper has concluded that as decrease of evaluation index,dangerous degrees of ground settlement of evaluation hazard in Cangzhou will be reduced from central city area inside second circle line to outside area.

该标准是以<供水水文地质勘察规范>(GB50027－2001)为基础进行编制的.它侧重和扩充了对勘查工作有实践指导意义的技术方法,纳入了近年来行之有效的新技术、新方法.能够对供水水文地质勘查起到具体的规范指导作用.它与<供水水文地质勘察规范>(GB50027－2001)相互关联,共同使用.

针对咸淡水界面运移预测的确定性模型方法的局限性,提出了非确定性模型--灰色突变理论模型方法,运用于浅层咸水入侵趋势的预测分析.该模型应用于黄河三角洲广饶县井灌区咸水的入侵发展趋势预测,研究成果表明,该方法快捷有效.