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61.
Suspended particulate matter (SPM) and colloidal matter (COM) in annual dry and wet deposition samples in urban Guangzhou were for the first time collected, and their trace metals were investigated by using inductively coupled plasma mass spectrometry (ICP-MS). The deposition flux of SPM and of metal elements varied largely among the investigated seasons, and reached the maximum in spring. The correlation analysis indicated that significant correlations existed among some of the metal elements in the deposition samples. The enrichment factors (EF) of metals in COM in the deposition ranging from 79.66 to 130,000 were much higher than those of SPM ranging from 1.65 to 286.48, indicating the important role of COM. The factor analysis showed that emissions from street dust, non-ferrous metal production, and heavy fuel oil were major sources of the trace metals. Positive matrix factorization (PMF) model was used to quantitatively estimate anthropogenic source.  相似文献   
62.
松辽盆地上白垩统陆相遗迹化石及其沉积环境   总被引:7,自引:4,他引:3       下载免费PDF全文
松辽盆地上白垩统中含有丰富的遗迹化石,通过对该盆地20余口取心井岩心的详细观察,发现了6大类动物遗迹化石15属20种。根据这些遗迹化石的分布规律,在松辽盆地上白垩统中划分出5种遗迹化石组合:(1)Scoyenia遗迹组合,主要成分有Scoyenia gracilis、Skolithos和Planolites,偶见停息迹化石,反映的是遭受周期性暴露的极浅水环境;(2)Skolithos遗迹组合,主要以Skolithos和Cylindricum十分发育为特征,分异度小,丰度高,反映的是高能动水环境。(3)Arenicolites遗迹组合,主要以Arenicolites和Polykladichnus大量发育为特征,还见有Skolithos、Planolites、Thalassinoides和逃逸迹等化石,分异度较高,反映了水流能量较低的浅水环境;(4)Planolites遗迹组合,以密集分布的Planolites十分发育为特征,分异度小,丰度高,见有少量指示缺氧环境的Chondrites化石,反映了水体较平静的还原环境;(5)Fuersichnus遗迹组合,主要由Fuersichnus、Glockeria、Gordia、Megagrapton和Planolites等遗迹分子构成,反映了相对平静的深水环境。  相似文献   
63.
Abstract: The Jinchuan deposit is hosted by the olivine-rich ultramafic rock body, which is the third-largest magmatic sulfide Ni–Cu deposit in the world currently being exploited. Seeking new relaying resources in the deep and the border of the deposit becomes more and more important. The ore body, ore and geochemistry characteristics of the concealed Cu-rich ore body are researched. Through spatial analysis and comparison with the neighboring II1 main ore body, the mineralization rule of the concealed Cu-rich ore body is summed up. It is also implied that Cu-rich magma may exist between Ni-rich magma and ore pulp during liquation differentiation in deep-stage chambers, which derives from deep-mantle Hi–MgO basalt magma. It is concluded that the type of ore body has features of both magmatic liquation and late reconstruction action. It has experienced three stages: deep liquation and pulsatory injection of the Cu- and PPGE-rich magma, concentration of tectonic activation, and the later magma hydrothermal superimposition. In addition, the Pb and S isotopes indicate the magma of I6 concealed Cu-rich ore body originates predominantly from mantle; however, it is interfused by minute crust material. Finally, it is inferred that the genesis of the Cu–Ni sulfide deposit is complex and diverse, and the prospect of seeking new deep ore bodies within similar deposits is promising, especially Cu-rich ore bodies.  相似文献   
64.
In order to collect baseline information on the environmental occurrence of volatile organic compounds (VOCs) in groundwater in East China, shallow groundwater samples were collected from five alluvial plains in East China in 2008 to 2009. All samples were analyzed for 54 VOCs representing a wide variety of uses and origins. Sampling sites were mainly selected in the areas to be susceptible to contamination from human activities in terms of previous hydrogeological survey. The data of all samples showed a variety of different hydrogeological systems with potential sources of VOCs, with 36 of the 54 VOCs being found. The most frequently detected compounds include naphthalene (56.9%), chloroform (16.9%), 1,2‐dichloroethane (16.2%), 1,2‐dichloropropane (13.1%), and 1,2,3‐trichlorobenzene (12.3%). The concentrations of methylene chloride, 1,2‐dichloroethane, carbon tetrachloride, trichloroethene, 1,2‐dichloropropane, and tetrachloroethene exceeded the relating drinking water standards. Future work will be needed to identify those factors that are most important in determining the occurrence and concentrations of VOCs in groundwater in China.  相似文献   
65.
1961-2010年青海省人体舒适度指数时空分布特征   总被引:3,自引:0,他引:3  
根据青海省50个气象观测站1961-2010年逐日气象资料, 对人体舒适度指数时空分布特征及其影响因子的权重进行了统计分析. 结果表明: 青海省人体舒适度主要为寒冷、冷、凉、凉爽和舒服等级, 整体呈现冷凉特征, 各区各等级年均日数分布差异较大. 青海省最不舒适的月份是1月份, 其次是12月; 最舒适的月份是7月, 其次是8月、6月. 1961-2010 年青海省人体舒适度指数上升趋势极显著, 与青藏高原气候变化趋势一致. 各区人体舒适度均呈显著上升趋势, 其中, 柴达木地区上升最明显; 春、秋季东部农业区和柴达木地区相似, 环青海湖地区和青南牧区相似, 各区秋季上升趋势均高于春季; 青南牧区各季人体舒适度年际波动幅度较大, 冬季环青海湖地区和青南牧区人体舒适度差异不大. 青海省人体舒适度季节差异明显, 夏季最高, 冬季最低, 春季略高于秋季, 近50 a来四季人体舒适度均呈显著上升趋势, 冬季波动幅度较大.温度(湿度、风速)与人体舒适度指数存在极显著的正(负)相关关系, 温度是影响人体舒适度指数的最主要因子, 风速和湿度主要通过温度影响人体舒适度指数, 且风速的负影响略大于湿度. 东部农业区和柴达木地区风速的负影响较大, 环青海湖地区和青南牧区相对湿度的负影响较大.  相似文献   
66.
云南个旧锡多金属矿田构造岩相成矿规律与西区找矿研究   总被引:1,自引:0,他引:1  
云南个旧超大型锡多金属矿田研究成果很多,但是西区找矿一直没有取得突破。本文以建造构造成矿综合研究为基本思路,综合前人的大量资料,重点为西区建立了新的构造岩相找矿模型。以中三叠统个旧组为沉积建造基础,晚白垩世发育花岗杂岩体建造。中生代晚期经历了大规模的岩浆热液成矿过程,成矿时代覆盖了70~90 Ma,集中在80 Ma左右,形成最主要的成矿岩相。通过矿田构造岩相成矿图的编制,发现成矿阶段处于挤压伸展构造转换体制,认为原始的个旧断裂两盘成矿是一致的,西区与东区的成矿模型是相同的。构造岩相的界面成为构造岩浆热液流体充填和交代蚀变两种主要矿床类型的有利空间。矿田构造地层岩浆即构造岩相成矿模型显示,由于个旧断裂垂直和水平方向多期次、规模性活动的改造,西区表现为高隆起、复杂错动的构造特点,因而成矿构造岩相具有残留性、复杂性、低位性等特征。依据上述研究成果,结合地物化信息,指出了西区找矿方向和有利区段。  相似文献   
67.
It is a worldwide challenge to explore the deeply buried deposits. Deep-penetrating geochemical exploration methods were developed to solve the problems of how to get the information of the buried deposits in the covered layer. The methods were successfully used to indicate some buried deposits, but not all kinds of deposits. What is more, a method cannot be used in all kinds of landscapes. In this paper, theories and case studies of deep-penetrating geochemical exploration methods, including mobile metal ions, enzyme leach, leaching of mobile forms of metals in overburden, electro-geochemical extraction method, biogeochemical exploration, nano-metal in geogas were reviewed. Elements migration, unloading mechanism and anomaly models are the most important parts for deep-penetrating geochemistry and need to be further investigated. From the perspective of economic efficiency and applicability, sampling and analyzing procedures should be simplified to improve the stability of all methods.  相似文献   
68.
济南地区的中基性岩体,大面积隐伏分布于济南市北部地带,零星出露为孤峰或丘陵,构成济南地区著名的"齐烟九点"地貌景观。药山为"齐烟九点"之一,地处济南杂岩体的中西部,岩性主要为闪长岩、辉长岩等,块状结构,节理裂隙发育,易球状风化形成临空状危岩体,构成崩塌地质灾害隐患。结合济南药山危岩体组合特征,进行了稳定性计算和分析,提出了不同的治理方案以及具体施工方法和施工顺序,以期达到消除地质灾害隐患的目的,切实保护人民生命财产安全,为类似地区开展地质灾害治理提供参考。  相似文献   
69.
文中研究在粒状铁化学还原三氯乙烯渗透反应格栅和生物降解苯和甲苯渗透反应格栅的联合格栅技术中,下游生物降解格栅中铁还原环境下微生物对苯和甲苯的生物降解。通过模拟粒状铁渗透反应格栅下游铁还原环境,主要研究微生物以苯、甲苯作为碳源时,对碳源的专一性。通过批实验发现,对于分别用苯和甲苯培养驯化的微生物,互换碳源后,微生物对2 000.00μg/L苯和甲苯的生物降解半衰期分别由之前的1.0和1.5 d减少到0.7和1.0 d,互换碳源后苯和甲苯的去除率分别增加38%和32%。在粒状铁渗透反应格栅下游生物降解渗透反应格栅中,微生物在铁还原环境下以苯、甲苯作为碳源时对碳源没有专一性,苯和甲苯可以同时被生物降解去除。  相似文献   
70.
2007~2010年云南GPS观测大气可降水量特征分析   总被引:2,自引:0,他引:2  
利用最新云南地基GPS站观测和探空观测资料分析表明:GPS/PWV和探空大气可降水量变化趋势一致,相关性好;云南省GPS/PWV年内干湿季气候特征分明,湿季开始前GPS/PWV月变率小于干季开始前的月变率;全省GPS/PWV年平均日变化峰值和谷值出现时间一致,勐腊、蒙自和昆明具有准双峰型特征;勐腊站干季、湿季日变化明显不同,其余测站干季和湿季的PWV日变化特征与全年平均日变化特征基本一致。GPS/PWV资料能够反应云南雨季开始期时空演变趋势。  相似文献   
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