天然河床渗滤取水工艺的原理与特点研究——以浠水南城水厂为例

渗滤取水净水机理主要是利用砂砾石层表面的泥膜及砂砾石层本身过滤作用、吸附作用,微生物的降解作用达到去除水中的悬浮物质、降低水的浊度、除菌的效果。以湖北浠水南城水厂渗滤取水工程为例,通过对渗滤工程特点和水质监测数据的研究,分析天然河床渗滤水水质及水源水水质的差异,以及渗滤水水质的可靠度。     

窑街三矿矿井水文地质特征及防治措施研究

根据生产实践总结，对窑街三矿矿井危害最大的是位于煤二层上部的第四系砾石层潜水，其次是烧变岩孔隙水与地表塌陷区积水，经多年水文地质资料分析，认为砾石层与地表水大通河水力联系密切，如采用帷幕注浆，打放水孔或泄水巷都不会取得好的效果，切断大通河与砾石层的水力联系，是根治砾石层最有效的方法，故要在充分研究大通河补给范围的情况下有目的地修筑拦河提与地下挡水墙，烧变岩孔隙水已利用打泄水巷，放水孔的方式排完，目前主要是严防地表水重新灌入，对塌陷区复垦，修筑防洪渠是防止大气降水进入塌陷区及防止地表水溃入矿井的有效途径。     

溆浦县栏桥—景江砂锡矿床地质特征

溆浦砂锡矿床床赋存在第四系冲积层中、锡石主要富集在度部砂砾石层。矿体呈层状，平均厚０．９２－１．６６ｍ，锡石平均品位６３２－１２２９ｇ／ｍ＾３。伴生锆石、独居石。本砂锡矿床与白马山风岗岩风化壳密切有关。矿床成因属第四系全新统冲积－堆积型细谷砂矿。     

辽南碧流河中上游砂金矿地质特征及成矿地质条件

辽南碧流河中上游砂金矿位于营口—宽甸台拱与复州台陷的交接部位。砂金主要赋存于碧流河及其支谷水系第四系全新统砂砾石层的底部,砂金矿体平行河谷呈层状分布;矿体埋藏浅,砂金粒度中粗,易采选;属冲洪积型谷底砂金矿。本区砂金主要来源于岩金矿和含金地层,成矿物质丰沛,成矿地质条件优越,是辽南砂金成矿的远景区。     

大兴安岭北段东坡扎兰屯地区高位砂砾石层研究及其地质意义

通过对大兴安岭北段东坡扎兰屯东南前新生代基岩上高位砂砾石沉积的展布、沉积特征、砾组特征及孢粉分析等研究,分析本套砂砾石层的成因及其气候环境记录,并结合区域资料,探讨其形成时代和新构造意义.分析结果表明,研究区高位砂砾石层可划分为Ⅰ级、Ⅱ级和Ⅲ级高位砂砾石层,沉积时代初步厘定为早全新世、晚更新世和中更新世.3级高位砂砾石层均为河流作用的冲积成因,水动力条件较强,略具冲积扇特征,分别为雅鲁河Ⅰ级、Ⅱ级阶地沉积记录和嫩江Ⅲ级阶地沉积记录.孢粉分析显示,Ⅱ级和Ⅲ级高位砂砾石层沉积时为针叶森林草原环境,气候温凉干旱;Ⅰ级高位砂砾石层沉积时为落叶阔叶森林草原环境,气候温暖偏干,其后变为草原荒漠环境,气候寒冷干旱.雅鲁河主河道晚更新世以来由东向西略有迁移,嫩江主河道中更新世以来由西向东不断迁移,雅鲁河断裂和嫩江断裂所夹的断块中更新世以来存在3期抬升.     

平安县洪水泉乡地下水分布规律及水文特征研究

以青海省平安县洪水泉乡地下水勘查为例,对该区域地下水赋存条件及分布规律、含水岩组划分及富水性、地下水补给、径流与排泄条件、地下水水化学特征进行研究,将区内地下水类型划分为第四系松散岩类孔隙水、碎屑岩类孔隙裂隙水、碳酸岩夹碎屑岩裂隙溶隙水、基岩裂隙水和冻结层水五大类,富水性分级与区域地下水一致。根据区内水文地质条件,离基岩山区近的村庄可以采用引泉方式解决供水,而远离基岩山区的低山丘陵村庄人畜饮水集中供水水源可采用大口井廊道取水工程来解决。通过合理开发利用地下水来解决当地供水需求。     

环境同位素在北京平谷盆地山前侧向补给研究中的应用

利用地下水水化学和同位素测试分析成果,结合区域地质、水文地质条件研究了平谷北山山区侧向补给情况和中桥水源地地区第四系松散孔隙水和下伏岩溶水关系。结果表明：研究区第四系松散孔隙水和基岩岩溶地下水均来源于大气降水,地下水化学类型均为HCO-3-Ca2+?Mg2+ 型;平谷北山山前基岩岩溶水侧向补给平原区第四系松散孔隙水和下伏岩溶地下水;通过D值估算得到中桥水源地第四系浅层地下水的山区岩溶水侧向补给和垂向降水入渗补给比例为57：43;中桥水源地基岩岩溶水接受山区岩溶水侧向补给和第四系孔隙水垂向越流补给比例为87：13。研究成果为平谷地区地下水资源量评价和地下水动力场数值模型的建设提供了关键参数,为区域地下水的合理开采和有序回补涵养提供了科学依据。     

环境同位素在北京平谷盆地山前侧向补给研究中的应用

利用地下水水化学和同位素测试分析成果,结合区域地质、水文地质条件研究了平谷北山山区侧向补给情况和中桥水源地地区第四系松散孔隙水和下伏岩溶水关系。结果表明：研究区第四系松散孔隙水和基岩岩溶地下水均来源于大气降水,地下水化学类型均为HCO₃^-—Ca²⁺·Mg²⁺型;平谷北山山前基岩岩溶水侧向补给平原区第四系松散孔隙水和下伏岩溶地下水;通过D值估算得到中桥水源地第四系浅层地下水的山区岩溶水侧向补给和垂向降水入渗补给比例为57∶43;中桥水源地基岩岩溶水接受山区岩溶水侧向补给和第四系孔隙水垂向越流补给比例为87∶13。研究成果为平谷地区地下水资源量评价和地下水动力场数值模型的建设提供了关键参数,为区域地下水的合理开采和有序回补涵养提供了科学依据。     

末次间冰期以来西宁市河谷沉积与环境

在西宁市区开展的钻探工作,获得了河谷平原区第四系的分布及沉积特征。通过对沉积厚度最大部位的2个钻孔岩芯的地层岩性、年代测试、孢粉组合及粒度分析等,探讨了西宁河谷平原区晚第四纪沉积与环境的关系。认为现今西宁市河谷平原内的主体沉积——低阶地沉积及上覆黄土堆积主要是末次间冰期旋回形成,在暖湿气候条件下沉积河流相砂砾石层,在干冷气候期接受风成黄土堆积,推测T3阶地形成于距今7.4万年前后气候由暖湿向干冷的过渡时期。     

基于水热耦合的青藏高原分布式水文模型——Ⅰ.“积雪-土壤-砂砾石层”连续体水热耦合模拟

青藏高原号称"亚洲水塔",是典型的高寒山区,其广泛存在的积雪、多年和季节冻土,影响了整个区域的水循环过程;青藏高原具有土层较薄、下伏砂砾石层较厚的特点,形成了特殊的"积雪-土壤-砂砾石层"水热介质结构。为深入研究青藏高原的水循环机理,本文选取尼洋河流域作为典型区,基于野外冻土水热耦合试验,结合青藏高原地质及气候特点,构建了包含12层"积雪-土壤-砂砾石层"连续体的青藏高原水热耦合模型,描述了完整的水热耦合模拟方程和参数计算方法。采用2016-2017年冻结融化期0~160 cm深度内的土壤和砂砾石层的温度、液态含水率和冻结深度的实测结果对模型进行了验证,各层温度模拟R2均值为0.91,冻结融化期内液态含水率模拟R2均值为0.52,土壤冻结深度模拟R2值为0.76。结果表明该模型在青藏高原地区有较好的适用性,可反映该地区冻结融化过程中土壤和砂砾石层水分与温度的特殊变化规律。     

长江三角洲北翼YBK1孔第四纪地层年代学研究

第四纪钻孔岩芯时间标尺的建立是分析平原覆盖区第四纪环境演变过程的重要基础。通过分析江苏扬州市施桥镇运河大桥东侧YBK1孔岩芯中总厚度95.50 m的第四纪沉积物的岩性、颜色、物质组成、沉积结构和接触界面形态等特征,并对地层进行详细分层基础上,综合采用AMS14C、光释光、宇生核素埋藏和古地磁等年代测试,建立了YBK1孔的第四纪地层年代标尺。结合地层的结构、构造、标志层等的标志,确定YBK1孔第四纪沉积物下覆地层为白垩系浦口组红色粉砂岩,第四纪地层自上而下可分为4套地层,从老到新分别为:中更新世晚期的启东组上段,发育时代为0.1~0.3 Ma,厚度30.20 m,以河床相砂砾层为主,成分较杂;晚更新世早期的昆山组下段,发育时代为0.1~0.045 Ma,厚度仅1.80 m,以残留的河床相砂砾为主;晚更新世晚期的滆湖组中段,发育时代为0.045~0.01 Ma,厚度仅3.40 m,以海滨形成的灰色粉细砂和灰黄色砂砾层为特征,晚更新世晚期的上段及下段均未见残留;全新世如东组沉积厚度较大,达55.10 m,可进一步分为上、中、下三段,分界年龄约为2.5 Ka和7.5 Ka。该区的全新世以滨海、河口、河漫滩沉积物为主,其厚度突然增大与全新世时期的河床改道密切相关。从YBK1孔的岩性特征分析,研究区域缺失早更新世及中更新世早期沉积物,中更新世晚期至晚更新世时期受河流侵蚀作用影响,以少量残留粗颗粒河床相沉积物为特征;全新世时期,因河流改道,地表水动力条件减弱,沉积了较厚的全新世沉积物。      

北京周口店地区Ⅳ阶地砾石层的发现及其意义

周口店河谷地区发现古宽谷地形及其相关的沉积物——Ⅳ阶地砾石层。砾石层形成于早更新世,是地表槽状流水作用的结果,命名为“捐兵湾组”。此地层的发现完善了周口店地区晚新生代地层系统,为重建北京猿人先期的古地理环境提供了科学依据。     

Alluvial deposits of a mud-dominated stream: the Red River, Manitoba, Canada

Abstract The Red River, Manitoba, is a mud‐dominated, meandering stream that occupies a shallow valley eroded into a clay plain. The valley‐bottom alluvium is the product of incision and lateral migration of river meanders. As revealed by a transect of five boreholes located across the floodplain at each of two successive river meanders, the alluvial deposits range from about 15 to 22 m thick and are composed primarily of silt. Sedimentary structures in the cores are weakly defined and consist mostly of beds of massive silt, thick (>0·4 m) massive silt and disturbed silt. Interlaminated sand and silt, and sand beds form relatively minor deposits, principally within the lower half of the alluvium, and thin beds of medium‐coarse sand and pea gravel can be present locally within the lower metre of the alluvium. The alluvium is interpreted to consist of overbank deposits from 0 to 2–3 m depth, oblique accretion deposits from 2–3 to 8–12 m depth and oblique accretion and/or channel deposits from 8–12 m to the base of the sequence. The massive bedding within the oblique accretion deposits is interpreted to represent the remnants of couplet deposits that were initially composed of interbedded, muddy silt and sand‐sized silt aggregates, as is consistent with the contemporary bank sedimentation. The post‐depositional disintegration and/or compaction of the aggregates has caused the loss of the sand‐sized texture. The disturbed silt beds are interpreted as slump structures caused by large‐scale rotational failures along the convex banks. Overall, the Red River represents a portion of a continuum of muddy, fine‐grained streams; where the alluvium lacks a distinct coarse unit, oblique accretion deposits form a majority of the floodplain, and large‐scale slump features are present.     

宜昌砾石层的沉积环境及地貌意义

宜昌砾石层上覆中更新世网纹红土,下伏白垩纪红层,共有22个岩性层组成,总厚超过100m。通过对宜昌地区剖面出露砾石层的沉积相分析表明,善溪窑和云池剖面由下至上出现冲积扇扇中-扇根亚相;李家院剖面与上述两剖面间有沉积间断,由下至上出现冲积扇扇端-扇中亚相。粒度分析也证明了该砾石层中的砂体属冲积扇中的辫状水道沉积,与沉积相分析所得结论一致。研究认为,宜昌砾石层具有典型的冲积扇沉积环境特征,主要为冲积扇扇顶部分。该冲积扇在宜昌东南地区如此大规模的发育,显示其形成时具有强大的水动力条件,通过对其形成的地貌环境意义进行探讨,初步认为,该冲积扇为长江三峡贯通的产物。据前人研究推断,宜昌砾石层的形成时代应该在1.08～0.73MaB.P.,三峡贯通应在1.0MaB.P.之前。     

新疆伊犁~巩乃斯盆地西段霍城县平原区地下水环境特征研究

新疆伊犁~巩乃斯盆地西段霍城县平原区是由多个冰水冲洪积扇形成的缓倾斜平原,赋存第四系松散岩类孔隙水。平原区北部岩性以漂石、卵砾石为主,粒径较大,为单一结构的孔隙潜水含水层,地下水接受补给强度大,地下径流速度快。孔隙承压含水层位于平原区中部和南部,岩性较为复杂,颗粒较细,卵砾石层、粗砂、亚粘土等互层,为复杂的多层含水层结构,地表水和大气降水的入渗是主要的补给来源,径流强度较弱。本研究利用92个不同深度的地下水样品全分析结果,对研究区水化学组分、水化学类型、水化学作用分带性进行了研究。研究表明：1）地下水中的K+、SO42-和Cl-变异系数均大于100%,反映了其含量具有较强的空间不均匀性;2）地下水化学类型具有分带性特征,沿径流路径上由北向南大致由HCO3-Ca-Mg型渐变为HCO3-SO4-Ca型,再渐变为HCO3-SO4-Ca-Mg型;3）研究区地下水矿化度和总硬度含量的变化不仅受到溶滤作用、蒸发浓缩作用的影响,还受到人类活动影响,具有明显的规律性,从补给区到承压区再到排泄区,可划分为3个水化学作用带。本研究结果为研究区地下水的合理开发、利用和保护提供了科学依据。     

Hydrogeophysical investigations for assessing the groundwater potential in part of the Peshawar basin,Pakistan

A large number of valleys and basin systems are present in the northwestern part of the Himalayas in Pakistan which form significant aquifers in the region. Hydrogeophysical investigations in the western part of Nowshera District, a part of the intermontane Peshawar basin, were undertaken to help to determine the availability of groundwater resources in the region. Thirty vertical electrical resistivity soundings (VES) were acquired using a Schlumberger expanding array configuration with a maximum current electrode spacing (AB/2) of 150 m in delineating the groundwater potential in the study area. The results of the interpreted VES data using a combination of curve matching technique and computer iterative modeling methods suggest that the area is underlain by 3 to 5 geo-electric layers. The interpretation results showed that the geo-electrical succession consists of alluvium comprising of alternating layers of clay, silty clay, fine to coarse sands, sand with gravels and gravels of variable thickness. High subsurface resistivity values are correlated with gravel–sand units and low resistivity values with the presence of clays and silts. The modeled VES results were correlated with the pumping tests results and lithological logs of the existing wells. The pumping test suggests the transmissivity of the aquifer sediments is variable corresponding to different sediments within the area. The gravel–sand intervals having high resistivity value show high transmissivity values, whereas clay–silt sediments show low transmissivities. It is concluded that majority of the high resistive gravel–sand sediments belong to an alluvial fan environment. These gravel–sand zones are promising zones for groundwater abstraction which are concentrated in the central part of the study area.     

Electrical resistivity ground imaging (ERGI): a new tool for mapping the lithology and geometry of channel-belts and valley-fills

Efforts to map the lithology and geometry of sand and gravel channel‐belts and valley‐fills are limited by an inability to easily obtain information about the shallow subsurface. Until recently, boreholes were the only method available to obtain this information; however, borehole programmes are costly, time consuming and always leave in doubt the stratigraphic connection between and beyond the boreholes. Although standard shallow geophysical techniques such as ground‐penetrating radar (GPR) and shallow seismic can rapidly obtain subsurface data with high horizontal resolution, they only function well under select conditions. Electrical resistivity ground imaging (ERGI) is a recently developed shallow geophysical technique that rapidly produces high‐resolution profiles of the shallow subsurface under most field conditions. ERGI uses measurements of the ground's resistance to an electrical current to develop a two‐dimensional model of the shallow subsurface (<200 m) called an ERGI profile. ERGI measurements work equally well in resistive sediments (‘clean’ sand and gravel) and in conductive sediments (silt and clay). This paper tests the effectiveness of ERGI in mapping the lithology and geometry of buried fluvial deposits. ERGI surveys are presented from two channel‐fills and two valley‐fills. ERGI profiles are compared with lithostratigraphic profiles from borehole logs, sediment cores, wireline logs or GPR. Depth, width and lithology of sand and gravel channel‐fills and adjacent sediments can be accurately detected and delineated from the ERGI profiles, even when buried beneath 1–20 m of silt/clay.     

青海共和盆地多石在沟河道沙丘现代风水交互过程

选择青海共和盆地多石在沟河道中6道新月形沙丘链作为研究对象,采用Trimble4700DGPS与常规测量手段,结合野外风沙观测与自动气象站数据,初步观测分析了2006年多石在沟河道沙丘在不同季节的形态变化过程,计算出2006年风季前比雨季后多石在沟河道沙丘体积减小了548.3m3,风积量为2351m3,流水的蚀平量为2899m3,2006年风水两相营力对河道沙丘的侵蚀贡献率约为45%∶55%,流水的搬运作用强于风力的堆积作用。但从较长的时间尺度来看,研究区的风力侵蚀作用强于流水侵蚀作用,河道沙丘不断增大。多石在沟河道沙丘是一个典型的风水交互作用系统,河道成为风力与流水交互作用的"中转站",在风水的交替作用下,沉积物由风积环境进入流水环境中。