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1.
笔者在进行崇礼山区1/20万水文地质测绘工作基础上,通过研究地区地下水的地球化学规律性,并结合区域水文地质条件与地质发展历史,对地下水化学成分的形成机理以及岩石的溶滤阶段进行了初步的探讨,认为本区地下水属大气起源的溶滤-渗入成因水,溶滤作用为其化学成分形成的基本作用,阳离子吸附作用与混合作用在一定程度上也影响着地下水化学成分的形成;溶滤作用发育不完全,岩石溶滤处于硫酸盐-碳酸盐过渡阶段。  相似文献   

2.
干旱区地下水咸化机制的区域氘盈余解析   总被引:1,自引:1,他引:0  
定量研究干旱区地下水的咸化机制对于水资源管理具有重要意义。针对已有研究需要考虑补给源水δ18O和δ2H值的局限,提出了一种利用区域氘盈余计算初始水、蒸发和溶滤对地下水咸化贡献的方法,并以罗山地区第四系地下水为例进行了分析。结果表明:该方法计算误差较小,可以有效区分蒸发和溶滤的贡献。地下水先溶滤后蒸发的自然咸化过程决定了溶滤作用的主导地位,咸化规模主要取决于溶滤作用程度。  相似文献   

3.
吉林省松嫩平原土壤盐渍化过程中的地下水作用   总被引:1,自引:0,他引:1  
吉林省松嫩平原从补给区到排泄区,地下水盐度逐渐增高,土壤盐渍化程度逐渐加重。作者采用3个模型(区域地下水流系统模型、风化—溶滤模型和蒸发—沉积模型)来模拟盐渍化的发生发展过程,这些模型与区内的地下水运移、土壤岩石的风化和沉积地质过程相一致,其中地下水是盐的迁移、聚积和排泄的主要地质载体。  相似文献   

4.
我国含油气盆地地下水系统可分为油田水系统和溶滤水系统,二者之间按电性、富水性和矿化度大致以上、下第三系为界.含油气系统按成藏过程及其地质特征分为生成系统、运移系统和聚集系统.地下水系统是流体系统的主体部分,它包含了含油气系统.油田水系统与含油气系统关系十分密切,油气的生成、运移和聚集过程都是在油田水参与下进行的.溶滤水系统影响并改造着含油气系统,油气藏会在溶滤水作用下遭到破坏.异常高压由排水固结的不均衡所形成,它的存在阻止了油田水向上运移.含油气盆地流体系统研究是现代水文地质学的一个新的研究领域,是油气成藏研究的一种有效途径.  相似文献   

5.
吉林省松嫩平原土壤盐渍化过程中的地下水作用   总被引:6,自引:0,他引:6  
吉林省松嫩平原从补给区到排泄区,地下水盐度逐渐增高,土壤盐渍化程度逐渐加重。作者采用3个模型(区域地下水流系统模型,风化-溶滤模型和蒸发-沉积模型)来模拟盐渍化的发生发展过程,这些模型与区内的地下水运移,土壤岩石的风化和沉积地质过程相一致,其中地下水是盐的迁移,聚积和排泄的主要地质载体。  相似文献   

6.
本文从地球化学角度出发,解析了方山玄武岩饮用矿泉水中化学成份的来源问题,对其水中化学成份形成的影响因素也作了探讨。本文确定了方山饮用矿泉的成因类型,揭示了影响化学元素迁移的因素,查明了地下水与围岩(含水岩组)相互作用的特征,建立了水一岩平衡,推导了元素在地下水中的迁移强度。影响水中元素迁移的因素有岩石的溶滤程度、组成岩石的矿物溶解度、地下水水动力条件、水化学特征和含水岩组的化学成份及其存在形式等。  相似文献   

7.
冀北坝上一带玄武岩地区广布富偏硅酸地下水,研究其形成机制及其水岩作用过程对矿泉水的合理开发利用与京津冀水源涵养功能具有重要意义.结合玄武岩地质建造地下水赋存特征,综合利用水化学分析,玄武岩岩石风化机制,水岩相互作用矿物平衡体系,δD、δ18O和δ13C同位素、14C放射性同位素测年等方法,剖析了汉诺坝玄武岩偏硅酸矿泉水形成的岩石地球化学风化和水文地球化学过程及地质建造制约因素.结果表明,研究区矿泉水为低矿化度的HCO3-Ca·Mg型与HCO3-Na·Ca型水,矿泉水形成类型有构造断裂深循环淋溶型和层状补给富集埋藏型2类.上层古风化壳地下水14C校正年龄约为4 050 a,地下水可溶性无机碳来源于土壤CO2与幔源CO2的混合作用.偏硅酸矿泉水的形成与分布受玄武岩地质建造制约,受岩石地球化学特征、岩石风化地表过程和水文地球化学响应过程控制.地下水中偏硅酸主要来源于玄武岩中斜长石、单斜辉石、镁橄榄石等硅酸盐矿物的风化水解;岩石矿物风化的水化学响应过程受溶滤作用控制,受阳离子交换作用影响.   相似文献   

8.
凡是位于地面以下的水都叫做地下水,它也是工、农业生产,国防建设和人们日常生活中不可缺少的一种自然财富。地下水的来源是雨水和雪水,它们从地面向下渗透,存在于土壤和石头的孔隙或裂缝里,就形成了地下水。地下水还有一个来源就是岩浆活动时分离出来的水蒸气,也往往在地下岩石的孔隙中凝结为地下水。地下水有以下三种不同的情况:①在疏松土壤中存在的水,叫壤中水;②在岩石孔隙或裂缝中的水,叫裂隙水;③在石灰岩,白云岩等特殊岩石分布的地区,由于地下水对这些岩石的溶解作用而形成了地下渠道,地下水在其中潛流,叫潛流水。我国广西桂  相似文献   

9.
包国良  周鹏鹏 《地下水》2012,34(5):28-30,48
溶浸采矿工艺是直接向花岗岩风化层中注入酸、碱等化学试剂,然后从浸出点抽取浸出液以获得所需元素。这一工艺显著的环境影响是化学试剂将会直接污染到花岗岩风化层中地下水资源。且在南方部分地区,花岗岩风化层往往会富集具有供水意义的地下水资源。在这种矿区地下水资源的保护显得尤为重要;研究分析矿区花岗岩风化层的地下水资源的水化学特征,结果表明,矿区地下水类型以HCO3-Na和HCO3-Na.Ca为主,且与该地区的地质背景情况有很好的对应关系,其成因是岩石风化与大气降水共同作用的结果,是大气降水渗入岩层并经过溶滤作用、阳离子交换吸附作用等复杂水文地球化学过程,最终形成现今的地下水类型。阐明矿区地下水水化学特征及其成因机制的基础上,对溶浸采矿区的地下水资源保护提出合理化建议。  相似文献   

10.
在乌蒙山1:5万五寨幅水文地质调查的基础上,采集地下水样品,结合地下水水化学组分聚类分析和因子分析方法,研究区域地下水化学特征,讨论其与水质评价结果的关系。结果表明,研究区地下水化学类型以HCO3-Ca型水为主,水化学组分具有明显的空间变异性。控制研究区地下水水化学组分的主要因素依次为水岩作用时间、含水层介质类型和人类活动。同位素测试结果印证了浅表地下水循环快、蒸发量较少,地下水的盐分来源以矿物的溶解和溶滤为主。盘河区域地下水水质较好,尤以玄武岩浅表风化裂隙富水结构中的A型水水质最优,适合作为该缺水区的开发利用水源。B型水多为沉积岩区典型的溶滤水。C型水为V类水,超标指标主要为SO42-,源于原生矿物溶解和废弃煤矿矿井涌水。D型水多经过中深部循环。通过聚类分析法识别地下水的形成演化过程,对在研究区开展供水井选址、发现矿泉水资源和水质评价有指导意义。  相似文献   

11.
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen.  相似文献   

12.
The Global Stratotype Section and Point (GSSP) for the base of the Silurian System was defined in 1985. Since that time, a number of researchers have suggested that this section has serious deficiencies for use as a GSSP. As a result, in 2000, the Subcommission on Silurian Stratigraphy (SSS) proposed undertaking a formal restu@ of this GSSP, which was subsequently approved by the International Commission of Stratigraphy (ICS). The result of this restudy was the formal proposal that the current GSSP, at 1.6 m above the base of the Birkhill Shale, at Dob's Linn, Scotland, should be maintained as the same locality and stratigraphic level, but the bios- tratigraphical definition of the boundary should be revised. The previously defined, basal Silurian grapto- lite zone, the Parakidograptus acuminatus Zone, should be subdivided into a lower Akidograptus ascensus Zone and a higher E acuminatus Zone. The base of the A. ascensus Zone, marked by the first appearance of A. ascensus, should be regarded as the biostratigraphic mark for the base of the Silurian. This proposal has now been formally approved by the SSS and ICS, and ratified by International Union of Geological Sciences. This is the first GSSP to undergo formal restudy and redefini- tion, and the proposal also included a recommended procedure for restudy of GSSPs.  相似文献   

13.
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″.  相似文献   

14.
Important tendencies in development of the world mineral-resources sector at the beginning of the 21st century were an increase in production and consumption of mineral materials differentiated by types of metals and nonmetallic mineral raw materials, by countries and regions, as well as the concentration of the production of mineral raw materials in a small number of countries, and a reduction in industrial reserves of minerals in the world economy, even at the current stage of their extraction. These tendencies should be taken into account in working out a strategy for development of the Russian mineral raw-material base.  相似文献   

15.
Taking the example of W Sudan, an analysis of the climatic incidents leading to the two recent famine disasters is made. On this natural background, the human side is investigated. Focus is directed towards the fragile economic structure of the famine-prone population groups. An early-warning system for famine in the Sahelian Zone is proposed taking grain production and storage, livestock development and the relationship between the prices of livestock and grain as major indicators.  相似文献   

16.
东濮凹陷北部沙三中亚段广泛发育盐岩和烃源岩,这两个看似不能共存的物质却在这里互层共生。该时期研究区沉积特征为多盐韵律与多层烃源岩互层共生、连续沉积,单个盐韵律厚度从几米到十几米,烃源岩有机质丰度高、类型好。平面上,两者在湖盆沉积沉降中心共生;垂向上,高有机质丰度、好干酪根类型与高盐度地层具有较好的对应关系。因而成为恢复古气候和古环境的重要研究对象。通过岩石学、古生物学以及Sr/Ba、B/Ga、(V+Ni+Mn)、Fe/Mn、Sr/Cu、Mg/Ca、V/(V+Ni)、稀土元素含量和氯同位素等方法对凹陷北部沙三中亚段的沉积环境进行研究。结果表明,凹陷北部沙三中亚段为深水沉积的还原环境,古盐度较高,达到半咸水-咸水沉积;微量元素和孢粉化石特征表明研究区沙三中亚段为温暖潮湿的环境。  相似文献   

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The structure of the eastern Pyrenees consists mainly of south-directed thrusts involving basement and cover rocks. An antiformal stack developed by the piling up of basement thrust sheets which outcrop in the Axial zone. These structures account for a thin-skinned thrust model rather than a vertical fault model in which the Axial zone would be essentially autochthonous, and the North-Pyrenean fault the axial plane of a fan thrust system. New data from the Eastern Pyrenees and the thin-skinned model suggest that(1) the structure east of the Pedraforca nappe is similar to that of the Central Pyrenees; (2) the cover rocks of the South-Pyrenean units and of the Axial zone-after restoration—built up a northwards-thickening prism consistent with the existence of a unique Pyrenean sedimentary basin during Mesozoic time; (3) the Axial zone is only a complex antiformal stack developed as a part of South-Pyrenean system related to the Paleogene thrusting-tectonics. The Axial zone palaeogeographic area had no special meaning during Mesozoic time.  相似文献   

20.
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning.  相似文献   

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