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1.
Snow samples were collected over a 3-year period from 2012 to 2014 at the Hailuogou glacier of Mountain Gongga (Mt. Gongga) and analyzed for 16 priority polycyclic aromatic hydrocarbons (PAHs) using Gas Chromatography–Mass Spectrometry (GC–MS). The results show that total average levels of the 16 PAHs ranged from 452 to 290 ng·L?1 with a possible declining trend from 2012 to 2014. Distances between the sampling sites and the emission sources were estimated at typically less than 500 km. The results suggest that the major source of PAHs was from coal combustion, while contributions from automobile exhaust played an important role in more recent years. This finding was in agreement with the characteristics of presence of local industry, residence, and recent development of tourism of the surrounding areas.  相似文献   
2.
从宏观基础地质入手,按矿床学的一些基本概念,针对东川-易门铜矿床地质地球化学特征,探讨了一些存在争议的重要问题。研究认为:狮山段是绿汁江组下部独立存在的地层层位;东川-易门式铜矿床属沉积-改造成因,其中的层状铜矿属沉积成岩成因,不是"热液成矿";所谓东川-易门式矿床(稀矿山除外)为"喷流沉积成矿"或"岩浆叠加",尚依据不足;刺穿体是构造作用产物,对成矿有利,是良好的找矿标志,其中的角砾岩主要是沉积角砾岩与构造角砾岩,或沉积-构造角砾岩,不足以冠名"隐爆角砾岩(筒)"。  相似文献   
3.
通过易门凤山铜矿床控矿构造解析与13~15中段南部矿体空间位置对比,矿体向SW深部侧伏,预测15中段2、4号矿体的SW端深部具找矿潜力。在纵投影图上,夹持矿体的"空当"呈现"阶梯、斜列、平行、等距"特点,表现出三个"空当"带与四个矿体带相间交替、平行斜列的组合型式。推测"阶梯空当"夹持的四个空白区为有利的找矿地段。在24号勘探线以南、15中段坑道开展1︰500断裂构造地球化学填图,圈定了5个铜异常和3个主要的元素组合(Cu-In-Bi-Hg-Sb)异常,其中,Ⅱ、Ⅲ号异常与"阶梯空当"定位的d、e位置相对应,为重点找矿靶区,对凤山铜矿床南部、深部找矿具有指示意义。  相似文献   
4.
云南楚雄中生代陆相盆地发育了良好的含煤、含铜和含膏盐的三位一体的建造组合。煤、膏盐和砂岩铜矿床中有机质在丰度、类型、成熟度、可溶有机质及生物标志物上既有一定差异,又有一定的相似性。煤和膏盐均参与了砂岩铜矿成矿作用,煤系为改造成矿作用提供了丰富的还原性有机质,膏盐提供了氧化性的SO2-4,间接提供了硫源。  相似文献   
5.
He  Haibo  Liu  Zaihua  Chen  Chongying  Wei  Yu  Bao  Qian  Sun  Hailong  Hu  Yundi  Yan  Hao 《中国地球化学学报》2019,38(5):613-626

Biological carbon pumping (BCP) is a key process in which dissolved inorganic carbon in terrestrial aquatic ecosystems is utilized by aquatic autotrophs for photosynthesis and transformed into autochthonous organic matter (AOC). However, the mechanisms underlying BCP and the amount of generated AOC deposited effectively, are still poorly understood. Therefore, we conducted a systematic study combining modern hydrochemical monitoring and a sediment trap experiment in Fuxian Lake (Yunnan, SW China), the second-deepest plateau, oligotrophic freshwater lake in China. Temperature, pH, EC (electrical conductivity), DO (dissolved O2), [HCO3], [Ca2+], SIc, partial CO2 (pCO2) pressure, and carbon isotopic compositions of HCO313CDIC) in water from Fuxian Lake all displayed distinct seasonal and vertical variations. This was especially apparent in an inverse correlation between pCO2 and DO, indicating that variations of hydrochemistry in the lake water were mainly controlled by the metabolism of the aquatic phototrophs. Furthermore, the lowest C/N ratios and highest δ13Corg were recorded in the trap sediments. Analyses of the C/N ratio demonstrated that the proportions of AOC ranged from 30% to 100% of all OC, indicating that AOC was an important contributor to sedimentary organic matter (OC). It was calculated that the AOC flux in Fuxian Lake was 20.43 t C km−2 in 2017. Therefore, AOC produced by carbonate weathering and aquatic photosynthesis could potentially be a significant carbon sink and may have an important contribution to solving the lack of carbon sinks in the global carbon cycle.

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6.
"改造成矿作用"是涂光炽院士提出的新理论。这一理论有如下基本论点和鲜明特色:矿质来源的广泛性;成矿流体的特殊性;成矿元素的活泼性;改造作用的内生性;断裂构造的主导性;赋矿岩石的多样性;改造矿床的普遍性;成矿作用的独特性与应有地位——矿床分类的四分法。滇中大姚-牟定式砂岩铜矿是典型的沉积-成岩-后生-改造成因。其主要论据与以下要素有关:裂谷成矿背景;矿源层(K、J)、矿源岩(元谋古陆);矿体受地层层位、岩相、岩性控制,其生成与煤系(提供有机质)、盐层(提供卤素)密切相关;矿体形态产状、矿石结构构造、成矿流体性状与水的来源、有机质类型及其作用在不同成矿期、成矿阶段显著不同。从岩石学的名词概念来解读和划分"改造成矿作用"的上限与下限:上限确定在后生作用之后,下限在变生作用之末。  相似文献   
7.
Lagoon behind stromatolite-reefs and bathyal areas in front of the reefs are the original basins where copper-bearing water was accumulated. The corresponding rock facies are the rear-reef bay syngenetic dolomite and the pro-reef black shale and dolomite respectively. Stratiform copper deposits were formed during diagnesis, being genetically connected with the stromatolite reef. No direct genetic relationship has been established between copper mineralization and volcanic tuffs.  相似文献   
8.
胡煜昭  吴鹏  冉崇英 《地质论评》2013,59(5):893-899
康滇古大陆裂谷的发生和演化造就了楚雄盆地,沉积出煤、铜、盐旋回与含矿建造和矿床组合.铜矿的生成(特别是改造富集)与煤(有机质)、盐(热卤水)密切相关.大姚—牟定式砂岩铜矿以其规模最大而具代表性.它的成矿作用的演化是从风化沉积作用到成岩作用、后生作用再到改造作用.作用的结果是分别产生含铜有机质沉积体、成岩矿层、后生矿层和改造富矿体.层状矿体赋存于砂岩浅紫交互带是氧化性流体与还原性流体相汇于斯而发生氧化—还原反应沉积成岩的结果.其金属硫化物的生成顺序与分带是遵循S、O、Fe、Cu热液体系中矿物共生组合规律的,随介质条件、四元素浓度的差异而变化.  相似文献   
9.
云南兰坪金满铜矿床改造成因的证据   总被引:6,自引:3,他引:3  
何明勘  严键 《地质与勘探》1998,34(2):13-15,18
从成矿物质来源、矿床定位场所、矿物包裹体、有机岩石学、生物标志化合物等几方面论述了兰坪金满铜矿床的改造成因证据,得到矿床产出于花开左组地层、富有机质暗色板岩与层间破碎带叠加处,改造有机质来源于深部、热演化程度较高等认识。  相似文献   
10.
有机—铜配合物热稳定性及热分解产物的实验研究   总被引:2,自引:0,他引:2  
庄汉平  冉崇英 《现代地质》1996,10(3):408-413
通过实验研究了富里酸、氨基丙酸和半胱氨酸3种有机质与铜的配合物的热稳定性及热分解产物特征。结果表明:富里酸—铜配合物在190~200℃时缩合成类干酪根物质,被富里酸配合的铜一同进入到该物质中去;氨基丙酸—铜配合物在140~150℃分解,形成π键配合物“二(三)氯·(乙炔)合铜(Ⅰ)”;半胱氨酸—铜配合物很不稳定,80℃便开始分解,生成黑色沉淀物“二水合四氯合铜酸铵”,而没有生成铜的金属硫化物  相似文献   
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