地下水的类型及特征.ppt
8.2 The Types and the Relevant Properties of Groundwater,Unsaturated Zone and Saturated Zone2.The Types and the Relevant Properties of Groundwater,unsaturated zone(非饱和带)saturated zone(饱和带)water of unsaturated zone:包气带水phreatic water:潜水confined water:承压水perched aquifer 上层滞水含水层,pore water:孔隙水fissure water:裂隙水karst water:岩溶水peak cluster(峰丛),peak forest(峰林)isolated peak(孤峰)cave(洞穴),stalagmite(石笋)stalactite(石钟乳),Unsaturated Zone and Saturated Zone包气带(zone of aeration)又叫非饱和带(unsaturated zone):地表与地下水面之间的地带饱水带(zone of saturation)又叫饱和带(saturated zone):地下水面以下的含水地带,Zone of aeration and zone of saturation,Zone of aeration and zone of saturation,2.The Types and the Relevant Properties of Groundwater(1)地下水 的分类 1)按地下水的埋藏条件,把地下水分为:包气带水(土壤水、上层滞水)潜水(phreatic water)承压水(confined water),Perched water,phreatic water,confined water,2)按含水层空隙性质,把地下水分为:孔隙水(pore water)裂隙水(fissure water)岩溶水(karst water),实际上,常常是两种分类相结合,如孔隙潜水、孔隙承压水,裂隙潜水、裂隙承压水,岩溶潜水、岩溶承压水等。,(2)包气带水 1)土壤水(Soil water)是土壤重要的组成部分,可呈气态水、结合水、毛管水形式。主要消耗在植物吸收和地面蒸发上,随季节性气候而变化。,2)上层滞水:包气带局部隔水层之上积聚的具有自由水面的重力水。上层滞水水量小,动态变化显著,只有在缺水地区才成为暂时性供水水源。,The configuration of a perched water table,(3)潜水(phreatic water)潜水:埋藏在地表以下,第一个稳定隔水层以上,具有自由表面的含水层中的重力水。,Phreatic water,(a)The geometry of the water table,illustrating the saturated zone,the unsaturated zone,and the capillary fringe.,(b)The surface of a permanent pond is the water table.(c)During the dry season,the water table can drop substantially,causing the pond to dry up.,The flow lines from the recharge area to the discharge area curve through the substrate.,1)潜水特点 潜水面(地下水面)形状变化与地形起伏一致;潜水补给区与分布区、排泄区一致;潜水受气象、水文因素影响很大;潜水积极参与水循环,资源易于补充、恢复,但受气候影响。其厚度有限,资源通常缺乏多年调节性。,The shape of a water table beneath hilly topography.,The phreatic water is easily contaminated.,When the water table rises,material above a weak sliding surface begins to slump(滑落),and a landslide may result.,2)潜水动态 潜水动态:在与环境相互作用下,含水层各要素(如水位、水量、水温、水化学成分等)随时间的变化,称为地下水动态。潜水动态的影响因素 a.气象因素 b.水文因素 c.地质因素,The change curve of phreatic water level in Jixian of Hebei Province,The influence of flood level in Laiin River on phreatic water,(4)承压水(confined water)承压水:充满于两个隔水层之间的含水层中的重力水。,The confined water in artesian basin of bedrock,承压水的特点:无承压水面,只存在承压水位;承压水补给区与分布区、排泄区 不一致;承压水受气象水文因素影响较小,其动态较稳定;承压水参与水循环不如潜水积极,因此资源不易补充、恢复,但因其厚度较大,其资源具有多年调节功能。,测压水位高于地表的范围是承压水的自流区,打在自流区里的井叫自流井。,The well-eruption of YangBa Well in Tibet,water column height 50m,The Laoshi Spring in Huangshi Park of America,The configuration of a city water supply,The configuration of an artesian system,This subsurface congiguration of aquifers leads to the formation of an oasis,where groundwater reaches the surface.,An oasis in the Sahara Desert,(4)孔隙水(Pore water)孔隙水:指赋存于松散沉积物颗粒构成的孔隙网络中的水。,孔隙水特点:有统一的地下水位,分布均匀,相互间有水力联系.1)洪积扇中孔隙水,The pore water in a proluvial fan,2)冲积平原中的孔隙水 如黄河冲积平原上,常见地上河,其常冲决自然堤。,The hydrogeological section beside the bank of the Yellow River downstream,2)冲积平原中的孔隙水,3)黄土高原中的地下水,黄土高原地下水水量不丰富,地下水位埋深大,水质较差。这是岩性、地貌、气候综合影响的结果。,The change curve of permeable coefficient for loess with depth,(5)裂隙水(Fissure water),裂隙水:存在于坚硬基岩各种裂隙中的水。1)成岩裂隙水 2)风化裂隙水 3)构造裂隙水,成岩裂隙水和构造裂隙水特点:一般没有统一的地下水位,分布不均匀和各向异性.各系统之间没有或有微弱的水力联系.风化裂隙水特点:分布比较均匀,无明显方向性,The water-wearing system with fissures,The sketch map of weathering fractures,(6)岩溶水(Karst water),岩溶水:是指赋存和运移于岩溶化岩体中的地下水。,The change by corrosion in fissure system of soluble rock,Joints act as conduits for water in cave networks.Thus,caves and passageways lie along joints.,1)岩溶水的垂直分带性 包气带(垂直循环带)季节变动带(过渡循环带)饱水带(水平循环带)滞流带(深部循环带),The vertical regions of Karst water,2)岩溶水的特点 岩溶水以管道流为主尤其是南方岩溶水的主要流动形式,表现为地下河。流速大(有的10cm/s),以紊流为主。,岩溶水分布的不均匀性极不均匀的:个体溶洞和单一管道;不均匀的:管道有一定的向外延伸,接纳支流、支管道;相对均匀的:岩溶管道呈网状发育,主、支管道交叉更迭,有统一的地下水位,有水力联系,各向异性小;,岩溶水的运动特征 有压流与无压流共存 明流与暗流共存;层流与紊流交替出现。,岩溶水的补给、排泄与动态 岩溶水的动态特征是水位、水量变幅大,变化迅速而缺乏滞后。这些特征反映了岩溶水补给、径流和排泄特点:降水灌入式地迅速补给,管道中畅通地径流,地下河系集中地排泄。,