油气藏上方汞异常成因机理浅析   总被引：4，自引：0，他引：4  

阳翔  赵友方  姚锦琪 《矿产与地质》2000,14(6):397-400

油气藏形成过程中的物理,化学变化使沉积物中富集的汞与有机物有相岂的迁移富集过程,因而地表汞异常对油气藏有指标作用。  相似文献   

Daily and inter-tidal variations of Fe,Mn and Hg in the water column of a contaminated salt marsh: Halophytes effect     

A.I. Lillebø  M. Válega  M. Otero  M.A. Pardal  E. Pereira  A.C. Duarte 《Estuarine, Coastal and Shelf Science》2010

It has been shown that salt marshes may function as efficient sinks for contaminants, namely for mercury. At the rhizo-sediment Hg may be associated with Mn and Fe oxyhydroxides, precipitated as sulphides or incorporated into organic matter. However, to our knowledge, in situ studies have not focused on the related processes at a daily or tidal cycle scales. Thus, the present work aims to study the effect of a common salt marsh halophyte in temperate latitudes (Sarcocornia perennis) on dissolved Fe, Mn and Hg concentrations in the water column. The in situ approach was carried out at a mercury-contaminated salt marsh and at the adjacent non-vegetated area (distance ≤ 4 m), covering two consecutive tidal cycles in order to include the photosynthetic active period and the night processes. During high tide no daily or spatial effects were observed on the concentrations of Mn, Fe and Hg in the water column, due to the dilution effect of the incoming seawater. During low tide the concentrations of Mn, Fe and Hg were significantly higher in the overlaying water column of the salt marsh. At S. perennis mats the concentration of dissolved total Hg was significantly related with the concentration of Mn (r = 0.459, p = 0.028, n = 23), but not with that of Fe (r = 0.367, p = 0.085, n = 23) while no significant relations were found at the adjacent non-vegetated sediments.  相似文献   

Magnetic characteristics of lake sediments in Qiangyong Co Lake,southern Tibetan Plateau and their application to the evaluation of mercury deposition     

Gao  Xing  Kang  Shichang  Liu  Qingsong  Chen  Pengfei  Duan  Zongqi 《地理学报(英文版)》2020,30(9):1481-1494

Heavy metals,one of the most toxic classes of pollutants,are resistant to degradation and harmful to the biological environment.The lakes that have developed on the Tibetan Plateau are ideal regions to investigate historic heavy metal pollution,particularly through the use of the reliable 210 Pb dating technique.Environmental magnetism has been successfully applied to estimate heavy metal pollution in different environmental systems due to its characteristics of simple processing steps,good sensitivity,and non-destructibility.However,it has not yet been applied to assess heavy metal pollution in lake sediments on the Tibetan Plateau.A series of environmental magnetic investigations of Qiangyong Co Lake sediments(southern Tibetan Plateau) was therefore conducted to explore the relationship between magnetic minerals and mercury(Hg) concentrations.The results showed that the magnetic mineral species in lake sediments remained stable,with similar levels of four different components from 1899 to 2011.However,the proportion of component 1(C1,hematite) increased continuously with the corresponding decrease in the proportion of C2(goethite),while the proportions of C3 and C4(magnetite) did not change significantly.As a result,the bulk magnetic signals(e.g.,SIRM and clf) were unsuitable for the evaluation of the Hg concentration;however,the proportion of hematite had a strong positive correlation with the Hg concentration.It is possible that the Qiangyong Glacier(the main water supply for Qiangyong Co Lake) has experienced faster melting with global and local warming,and the Hg trapped in cryoconite and ice was released.Hematite,with a large specific surface area,has a strong capacity for absorbing Hg,and both materials are ultimately transported to Qiangyong Co Lake.The proportion of hematite in a sample is therefore a suitable semi-quantitative proxy that can be used to evaluate the Hg concentration in Qiangyong Co Lake sediments.This study confirmed that the variation of magnetic minerals can provide a new method to estimate the variation of Hg concentrations and to study the process of Hg deposition in lakes in the southern Tibetan Plateau on the basis of a detailed environmental magnetic analysis.  相似文献   

Effects of mercuric chloride on antioxidant system and DNA integrity of the crab Charybdis japonica     

Hongxia Zhang  Luqing Pan  Jingjing Miao  Chaoqun Xu 《中国海洋大学学报(英文版)》2009,8(4):416-424

Mercury (Hg) is one of the commonly encountered heavy metals, which is widespread in inshore sediments of China. In order to investigate the toxicity of Hg on marine invertebrates, we studied the effects of the divalent mercuricion (Hg²⁺) (at two final concentrations of 0.0025 and 0.0050 mg L⁻¹, prepared with HgCl₂) on metallothionein (MT) content, DNA integrity (DNA strand breaks) and catalase (CAT) in the gills and hepatopancreas, antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), in the hemolymph, gills and hepatopancreas of the portunid crab Charybdis japonica for an experiment period up to 15 d. The results indicated that MT was significantly induced after 3 d, with a positive correlation with Hg²⁺ dose and time in the hepatopancreas and a negative correlation with Hg²⁺ dose and time in the gills. While CAT in the hemolymph was not detected, it increased in the hepatopancreas during the entire experiment; SOD and GPx in the three tissues were stimulated after 12 h, both attained peak value and then reduced during the experimental period. Meanwhile, DNA strand breaks were all induced significantly after 12 h. These results suggested the detoxification strategies against Hg²⁺ in three tissues of C. japonica.  相似文献   

Tissue-specific bioaccumulation and oxidative stress responses in juvenile Japanese flounder (Paralichthys olivaceus) exposed to mercury   总被引：1，自引：0，他引：1  

黄伟  曹亮  叶振江  林龙山  陈全震  窦硕增 《中国海洋湖沼学报》2012,30(4):569-579

To understand mercury (Hg) toxicity in marine fish, we measured Hg accumulation in juvenile Japanese flounder (Paralichthys olivaceus) and assessed the effects on growth and antioxidant responses. After Hg exposure (control, 5, 40, and 160 μg/L Hg) for 28 d, fish growth was significantly reduced. The accumulation of Hg in fish was dose-dependent and tissue-specific, with the maximum accumulation in kidney and liver, followed by gills, bone, and muscle. Different antioxidants responded differently to Hg exposure to cope with the induction of lipid peroxidation (LPO), which was also tissue-specific and dosedependent. As Hg concentration increased, superoxide dismutase (SOD) and catalase (CAT) activities increased significantly, whereas glutathione S-transferase (GST) activity and glutathione (GSH) levels decreased significantly in the gills. SOD and glutathione peroxidase (GPx) activities and the GSH level increased significantly in the liver. SOD activity and GSH levels increased significantly, but CAT activity decreased significantly with an increase in Hg concentration in the kidney. LPO was induced significantly by elevated Hg in the gills and kidney but was least affected in the liver. Therefore, oxidative stress biomarkers in gills were more sensitive than those in the liver and kidney to Hg exposure. Thus, the gills have potential as bioindicators for evaluating Hg toxicity in juvenile flounder.  相似文献   

Role of organic acids in desorption of mercury from contaminated soils in eastern Shandong Province, China   总被引：2，自引：0，他引：2  

Hong Jiang  Lei Zhang  Binghui Zheng  Guoqiang Wang 《中国地理科学(英文版)》2012,22(4):414-421

Batch experiments were conducted to study the effects of low-molecular-weight organic acids(LMWOAs) on desorption of Hg from two kinds of soils in the eastern Shandong Province,China.Of all LMWOAs,oxalic and citric acids were chosen as the representatives in this experiment because they are most common in soils.Desorption of Hg increases with the increase of extracting time,until the highest desorption amount at 6-8 h,and then declines.It indicates that timeliness is very important when organic acids are used for phytoremediation in contaminated soils.When the concentrations of organic acids increase from 1.0 mmol/L to 10.0 mmol/L,Hg desorption increases significantly regardless of oxalic or citric acid.Compared with oxalic acid,citric acid is more effective to enhance the desorption of Hg,especially from fluvo-aquic soil.With the increase of initial pH value from 3 to 8,Hg desorption decreases directly in the presence of oxalic acid.However,Hg desorption first decreases,then increases,and eventually decreases again in the presence of citric acid due to the variation of competitive ability between chelating of citric acid and adsorption of soil in different pH values.Citric acid showed greater ability to release Hg from soils than oxalic acid.According to the results of the present study,it is found that the bioavailabilities of heavy metal can be improved with selecting suitable types and concentrations of organic acid amendment and reasonable soil condition.  相似文献   

城镇周边土壤Hg异常成因机理研究     

马生明  朱立新  汤丽玲  王之峰 《地质学报》2007,81(4):570-576

普遍出现在城镇及其周边土壤中的Hg异常受到极大关注,但是对此类异常到底具有怎样的生态危害目前还没有明确的结论原因之一就是对异常的成因机理缺乏准确认识。在13个中心试验区及其周围几十个城镇获得的试验研究结果表明,出现在城镇周边地区的土壤Hg异常,均与土壤中的辰砂矿物有关,而且辰砂在形成土壤Hg异常中起到重要作用。此类辰砂是叠加到土壤中的Hg经过形态转化形成Hg2 ,然后与S2-结合生成HgS,进而结晶形成的首次给辰砂的次生成因学提供了一种可能性。辰砂的形成使Hg以矿物态形式固定在土壤中,导致土壤Hg含量增高,形成土壤Hg异常。此项研究成果对土壤Hg异常生态效应评价及预警预测研究具有重要意义。  相似文献   

汞、镉、硒对刺参(Apostichopus japonicus)幼参的单一毒性与联合毒性     

孙振兴  王慧恩  王晶  刘金川  张婕  张莺  吴传艳 《海洋与湖沼》2009,40(2):228-234

在水温15.5-17.0℃的静水条件下,以Hg2+、Cd2和Se4+对刺参幼参进行了单一毒性和联合毒性实验.联合毒性实验采用等毒性配比法,并以Marking相加指数评价联合毒性效应.单一毒性实验结果表明,Hg2+、Cd2+、Se4+对刺参幼参急性毒性的96h半致死质量浓度(LC50)分别为0.0912、4.6433和0.7413mg/L,三者对幼参的毒性大小依次为Hg2+>Se4+>Cd2+.Hg2+、Cd2+、Se4+对刺参幼参的最大容许质量浓度分别为0.0009、0.0464、0.0074mg/L.联合毒性实验结果表明,当Hg2+-Cd2+、Hg2+-Se4+以及Cd2+-Se4+分别以等毒性混合物共存时,它们对刺参幼参在24h、48h、72h和96h的联合毒性均为拮抗作用;当Hg2+-Cd2+-Se2+三者以等毒性混合共存时,它们对刺参幼参在24h、48h、72h和96h的联合毒性仍为拮抗作用.讨论了Hg2+、Cd2+、Se4+对刺参幼参联合毒性效应的机制.  相似文献   

明长陵土壤地球化学特征     

陈出新  郭莉  赵冬冬  吕金波 《城市地质》2015,(2):52-55

对明长陵陵墓和外围土壤特征开展地球化学研究,发现长陵陵墓土壤Cl、S、P、N、C、Hg、Au和有机质含量在表层显著富集,陵墓内土壤各元素含量高于外围土壤。陵墓内五供两侧土壤Hg和Au元素含量出现异常,影响皇陵外东南向土壤Hg,以及南向和西南向土壤Au含量。陵墓土壤稀土总含量略有差异,但土壤稀土元素分布模式相似,表明陵墓内土壤为同源物质。  相似文献   

Sb–Hg ore deposit distribution controlled by brittle structures: The case of the Selvena mining district (Monte Amiata, Tuscany, Italy)     

Andrea Brogi  Lorenzo Fabbrini  Domenico Liotta 《Ore Geology Reviews》2011,41(1):35-48

This paper deals with the tectonic control on the hydrothermal system that gave rise to Sb–Hg ore deposits in the Monte Amiata area that was one of the most relevant mining district for the exploitation of mercury in Italy. The study area (Selvena mining district) is located in southern Tuscany (inner Northern Apennines) one of the most important mineralized area in the western Mediterranean region. Southern Tuscany was severely affected by Middle–Late Miocene low-angle normal faults, later dissected by Pliocene–Pleistocene faults, coeval magmatism (Late Miocene–Pleistocene) and hydrothermal activity (Pliocene–Present). The Selvena mining district is located south of Middle Pleistocene Monte Amiata volcanic complex. Our structural and kinematic study is based on the integration among fieldwork, borehole and mine data. The results highlight two Pleistocene–Holocene left-lateral transtensional shear zones linked by normal faults, defining a coeval pull-apart structure. Here, the Sb–Hg mineralization, transported by meteoric hydrothermal fluids mainly, is particularly diffuse and concentrated in the cataclasites and in damage zones of the normal faults. Furthermore, a widespread mineralization also occurs in the cataclasites of Miocene low-angle normal faults. Mine evidence suggests that ore-bearing fluids percolated through structural conduits located along the fault planes and resulting parallel to the intermediate stress axis. Geological structures and ore deposit distribution are related to a single hydrothermal circuit, with meteoric water channelled to depth through conduits parallel to the intermediate stress axis of the transcurrent shear zones; then, hydrothermal fluids mainly ascended through the almost vertical deformation zones located at the intersection between normal and strike-slip faults. Thus, hydrothermal fluids permeated also the Middle–Late Miocene cataclasites. This study shed light on the relationships between geological structures and mineralization in southern Tuscany and underlines the importance to investigate mine areas to understand hydrothermal fluids path.  相似文献