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1.
山东金岭铁矿属接触交代型矿床.沿金岭闪长杂岩体与中奥陶统马家沟组灰岩、中石炭统本溪组砂、页岩的接触带上分布有肖庄、侯庄、铁山、北坑、北金召、东召口、王旺庄等多个大小不等的矽卡岩矿床.通过对分布于中奥陶统马家沟组灰岩中膏盐、硫化物、矿体和矽卡岩、岩体赋存的硫酸盐、硫化物进行δS~(34)的分析,获得了金岭闪长岩体的硫同位素组成δS~(34)=-0.4~14.6‰,δS~(34)的众值范围:4.3~9.8‰,沉积围岩的δS~(34)=-1.4~18.1‰,δS~(34)的众值范围:7.2  相似文献   

2.
河北平原地下水硫酸盐34S和18O同位素演化特征   总被引:1,自引:0,他引:1  
地下水中硫酸盐的34Ss和18O在探寻地下水的水质演化规律、赋存环境特征方面具有重要的研究意义,笔者选取保定-河间-沧州-黄骅剖面采集深层地下水水样,分析测试了其主要阴阳离子含量、δ18O、δD、14C及δ34Sso42-和δ18Oso42-各项指标,在此基础上首次探讨了河北平原地下水中硫酸盐的硫、氧同位素分布特征与演化机理.研究发现研究区地下水硫酸盐的δ34Sso42-值沿地下水流向增大,δ18Oso42-值则在一个较小的范围内波动,最终接近一个常数值,二者间呈现较好的负相关关系;δ34Sso42-值随地下水14C年龄的增加而增加,δ34Sso42-则随地下水14C年龄的增加而趋于稳定;34Sso42-值与r(so42-)/r(C1-)的值呈负相关关系,δ18Oso42-值与r(SO42-)/r(C1-)的值则呈正相关关系.在研究区地下水中硫酸盐的34S和18O同位素的分布演变特征主要由SO42-和水之间的同位素交换反应、微生物硫酸盐的还原作用、硫化氢的再氧化作用所影响,其中微生物硫酸盐的还原作用的结果使地下水中的硫酸盐富集34S,SO42-和水之间的同位素交换反应是影响地下水的δ18Oso42-值的主导因素,使地下水的δ18Oso42-取决于地下水的氧同位素组成.  相似文献   

3.
淮北煤田太原组灰岩水年龄及同位素地球化学特征   总被引:1,自引:0,他引:1       下载免费PDF全文
陈松  桂和荣 《中国地质》2019,46(2):337-345
为了解淮北煤田太原组灰岩水年龄、水化学特征及演化,采集了淮北煤田29个矿井地下水样品进行水常规、氢氧同位素及~(14)C测试。利用传统图示及统计方法探讨了地下水化学特征及演化,约束了地下水年龄及径流特征。结果表明:淮北煤田太原组灰岩水年龄在2900~21910 a之间变化,不同矿区之间灰岩水化学特征有明显差异。闸河矿区以较低的TDS浓度、最小的地下水年龄和最高的δD和δ~(18)O值为特征,为淮北煤田太原组灰岩水主要的补给区;临涣矿区孙疃矿、宿县矿区桃园矿具有较大的地下水年龄、较高的TDS浓度和低的δD和δ~(18)O值,为主要排泄区。TDS浓度等值线图和地下水年龄等值线图呈现一致的演化规律,淮北煤田东北部闸河矿区为主要补给区。太原组灰岩水径流特征主要受构造背景的控制,地下水补给条件及水岩相互作用程度决定了水体中TDS浓度和氢氧同位素富集特征。  相似文献   

4.
《地下水》2017,(6)
喀什平原区是沙漠与戈壁交界的绿洲平原,属于典型的水质型缺水地区,地下水的化学特征主要表现为高硫酸盐、高硬度、高矿化度。本文针对喀什平原区300 m以浅钻孔中完成的地下水样品硫同位素进行测试,结果显示,地下水中δ34S值均为正值,δ34S值范围为2.1‰~13.6‰之间。采用统计、对比分析的方法 ,研究了喀什平原区地下水中硫同位素分布特征及其硫酸盐来源,表明研究区地下水中的硫酸盐主要来自于不同沉积相蒸发岩的溶解以及大气降水的补给。从区域分布看,南部盖孜河地下水流亚系统的地下水中硫酸盐浓度相对较低,北部克孜勒河地下水流亚系统的地下水硫酸盐浓度较高,沿水流方向,SO42-的浓度逐渐增加,而δ34S值变化不大,是蒸发浓缩和沿程累积共同作用的结果。研究结果为喀什平原区水质典型缺水地区的地下水资源开发、利用与保护提供科学依据。  相似文献   

5.
朱沉静  李俊霞  谢先军 《地球科学》2021,46(12):4480-4491
为深入探究地下水系统中影响碘迁移转化的主控水文生物地球化学过程,对大同盆地典型高碘地下水区完成样品采集,分析地下水样品基础理化性质及碳硫同位素组成特征.结果表明,大同盆地地下水碘含量变化范围为14.40~1 030.00 μg/L,高碘地下水(I>100 μg/L)主要分布在盆地中心排泄区.地下水中溶解性无机碳的δ13CDIC值变化范围为-12.11‰~-9.79‰,硫酸盐δ34SSO4值介于4.04‰~16.63‰.δ13CDIC和DOC之间存在较明显的正相关关系,表明有机质的微生物降解过程是区域地下水无机碳的重要来源之一.同时,δ13CDIC与δ34SSO4一定的负相关关系表明硫酸盐是有机质微生物降解过程中潜在电子受体之一,且地下水水环境以偏还原环境为主.高碘地下水表现出低δ13CDIC、高δ34SSO4的同位素特征,表明有机质的微生物降解过程是控制地下水中碘迁移释放的主要过程之一,与该过程相伴而生的碘形态转化进一步促使碘以碘离子的形式在偏还原的地下水环境中发生富集.   相似文献   

6.
娘子关泉域岩溶水硫酸盐污染的地球化学模拟分析   总被引:8,自引:1,他引:7       下载免费PDF全文
李义连  张江华 《地球科学》2000,25(5):467-471
通过分析娘子关泉域岩溶水的水文地球化学特征, 发现沿流动路径上硫酸根质量浓度逐渐降低, 矿化度逐渐降低, Ca2+, Mg2+与SO42-比值逐渐升高等特征.运用水岩作用的地球化学模拟软件模拟得出, 广泛出露分布的中陶统灰岩因含石膏而使地下水在补给—径流区和地下浅部即含有高硫酸根, 沿流动路径上在汇流区—排泄区地下水不断有侧向补给及与深部水的混合, 而表现出硫酸根质量浓度逐渐降低; 同时个别特高硫酸根的井水为石炭—二叠系中水污染中奥陶统含水层造成的.相对而言, 深部下奥陶统含水层的水质较好.   相似文献   

7.
溶解性有机碳(DOC)是地下水中微生物代谢活动的主要能量来源,δ13CDOC值是指示DOC来源及生物代谢活动的重要参数.通过对石家庄地区浅层地下水中DOC浓度及δ13CDOC特征进行分析,结合相应的水化学检测,探讨了δ13CDOC值对地下水环境演化的指示作用.结果表明:DOC浓度及其同位素特征均受到天然及人为两方面影响,表现出一定的空间特征.在垂向上,除石家庄西北部地区以外,研究区地下水中DOC浓度随地下水埋深的增大有降低趋势,δ13CDOC随地下水埋深的增大而增大;石家庄西北部地区具有一定特殊性,地下水埋深较浅,交替强烈,TOC含量较高,而DOC浓度较低,δ13CDOC值偏负.在水平方向上,滹沱河沿岸地区,沿地下水流向,DOC浓度逐渐降低,δ13CDOC值逐渐偏正.石家庄南部地区受污灌影响,DOC浓度较高,δ13CDOC值偏负.研究区地下水埋藏深度、补给条件、径流特征以及人为作用均对地下水中DOC浓度及其同位素特征产生显著影响.δ13CDOC值与SO42-、NO3-浓度的相关关系指示出研究区地下水中反硝化作用和硫酸盐还原作用的发生,从吴家营、宋营一带开始逐渐由硝酸盐还原环境向硫酸盐还原环境过渡;沿地下水流向,地下水环境还原程度增强.  相似文献   

8.
稳定同位素因其指纹效应已成为分析矿区污染来源的重要技术手段。文章以招远金矿区为例,应用硫同位素联合水化学分析、聚类分析及氢氧同位素分析招远金矿区水污染特征和成因。通过分析可知,矿区内地表水和地下水主要接受大气降水补给,水力联系密切。水化学类型以SO4—Ca和SO4—Na型为主,阴离子以SO42-为主,地表水和地下水的NO3-和Cl-在空间上变异性较大。地表水硫酸盐含量普遍偏高,硫酸盐污染较为严重,高值区出现在玲珑金矿、金翅岭金矿和张星镇附近;而地下水高值区都出现在玲珑金矿附近,且SO42-浓度沿着径流方向逐渐降低。地表水中硫酸盐δ34S值介于1.8‰~9.8‰,地下水中硫酸盐δ34S值介于2.7‰~9.6‰,地表水和地下水硫酸盐含量受玲珑金矿硫化、玲珑花岗岩和胶东岩群影响明显。在地下水径流途中,有地表水入渗污染地下水的现象。另外,工业废水的排放也是硫酸盐含量升高的主要原因。研究表明:硫同位素在金矿区硫酸盐污染的来源和特征方面有很好的指示作用,是评价矿山开采对地下水污染的有效工具。  相似文献   

9.
通过分析长江三角洲扬泰靖地区第四系松散层地下水硫酸盐的硫同位素组成特征,揭示不同层次和地段地下水中硫酸盐的演化规律及其赋存环境变化特点。研究表明潜水中硫同位素值变化不大,8.3‰~10.5‰,而孔隙承压水中硫同位素值变化较大,随深度增加而增大(最高达71.6‰)。在潜水中,硫酸盐源于农业污染或污染物与海源硫酸盐的混合;在顶部地区和沿江地段的浅层孔隙承压水中,负δ34S值的硫酸盐源于硫化物的氧化,与其松散层岩性以砂性土为主、径流条件好、封闭性差和处于氧化环境有关;而在东部的深层孔隙承压水中,高δ34S值的硫酸盐源于硫酸盐的还原,与其松散层岩性以粘性土为主、隔水层发育、径流条件差、封闭性好和处于还原环境有关。  相似文献   

10.
对山西大同口泉沟南寒武-奥陶系碳酸盐岩地下水(岩溶水)资源的开发研究中,利用不同价态硫富集34S的不同以及硫同位素分馏,主要是硫酸盐和硫化物中δ34S(SO42-)、δ34S(HS-)的变化,分析了岩溶水的来源,区分出表征循环交替和补给条件的三种地下水类型和环境,识别出口泉南水文地质区内各个地下水子系统及其相互关系。对岩溶水开发中泉域划分问题,使用硫同位素之间的关系,并结合硫酸盐中氧同位素δ18O(SO42-)以及14C关系,表明本区与相邻的两泉域相互独立。岩溶水中δ34S(SO42-)、δ34S(HS-)和δ18O(SO42-)有很大变幅,神头泉Z1岩溶水有罕见的异常值。  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.
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   

15.
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17.
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   

18.
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   

19.
郯庐断裂南段研究进展与断裂性质讨论   总被引:13,自引:3,他引:13  
据1:5万区域地质调查和专题研究资料,就郯庐断裂带是否南延与消失的原因,其与大别—苏鲁造山带交截形成的假位错效应,以及与中新生代沉积盆地形成演化的关系等作了新的阐述。在此基础上,讨论了郯庐断裂带是否为巨大的左行平移断层或转换断层。认为郯庐断裂带可能是在“古郯庐带”的基础上于早侏罗世重新活动、白垩纪强烈活动的地堑型枢纽断裂带。  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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