企鹅粪土层中石英砂表面的化学溶蚀形貌及实验模拟

利用电镜扫描的方法分析了南极阿德雷岛Y2湖企鹅粪土沉积层中石英砂微形貌的特征,发现在企鹅粪含量高的沉积层中石英砂表面具有明显的碗状溶蚀坑等化学溶蚀特征,这一溶蚀特征在Y2湖企鹅粪含量低的沉积层和研究区的其他未受企鹅粪影响的沉积环境中均未明显出现。为了揭示这一特殊化学溶蚀现象的作用机制,根据Y2湖企鹅粪土沉积层自然沉积环境,通过条件实验确定在实验室内使用酸性较高的氟溶液(1mol.L-1HF溶液)对石英砂进行溶蚀实验,通过对比分析发现,实验室模拟条件下可以得到与企鹅粪土沉积层中石英砂相近的表面微形貌特征,这表明它们是在相似的过程中形成的。企鹅粪土沉积层酸性高氟环境中可能存在的HF酸化学溶蚀作用是形成企鹅粪土层中石英砂表面特有溶蚀坑的主要原因。在南极特殊的自然条件下碗状溶蚀坑与企鹅粪之间存在一定的因果关系,从而使石英砂的表面微形貌分析成为南极企鹅生态研究的一种新的辅助手段。     

质子探针分析方法研究矿石中微细粒金的赋存状态——以皖中沙溪斑岩铜(金)矿床为例

本文应用先进的微束分析技术——质子探针分析方法对安徽中部沙溪斑岩铜（金）矿床中金的赋存状态进行系统的研究。结果表明,该斑岩铜（金）床中金的赋存状态以微细粒微米级的自然金形式存在,其载体矿物主要为黄铁矿和黄铜矿。本研究对斑岩铜（金）矿床中金的综合利用提供了理论上的依据,同时也为其它同类矿床中金的赋存状态提供了新的研究方法。     

近2000年来南极菲尔德斯半岛西湖沉积物中稀土元素1/δEu特征与气候演变

测试分析了近2000年来南极菲尔德斯半岛西湖沉积物中的部分稀土元素和微量元素丰度。稀土元素的分配模式表明沉积物主要来自周围的母岩风化产物。相对于Cs/Rb,La/Yb和Sr/Ba而言，1／δEu随深度的变化与沉积物中反映生物强度变化的S元素丰度的波动明显一致，且与近2000年来该地区降水量的变化几乎同步。这表明尽管稀土元素Eu没有出现明显的异常变化，但是，1／δEu对历史时期的气候变化和生物活动强度有很好的响应关系，能够用来反演古气候环境的演变。     

An assessment of variations in mercury deposition to Antarctica over the past 34,000 years

We performed a comparison analysis of the variations .in Mercury ( Hg) concentrations and the precipitation proxies ( e. g. , 18 O values and 10 Be concentrations) in the Dome C ice core. The results showed that there were significant correlations between Hg and δ 10O values, 10Be concentrations, indicating that the accumulation rate in Dome C is one of the key factors controlling the variations of Hg concentrations in the past 34 ,000 years, and implying that Hg concentrations in ice core can be used as another reliable proxy of precipitation rate in Antarctica. Based upon the high-resolution δ 18O values, we estimated the variations in mercury deposition flux to Antarctica over the past 34,000 years. The highest mercury deposition flux is about 3. 80 pg cm-2 yr-1 during the Last Glacial Maxium (LGM) as high as 3. 5 times of the mercury deposition flux ( about 1. 08 pg cm -2 yr -1) in Holocene due to the fluctuations in natural mercury emissions such as the oceanic biological emissions.     

Geochemical studies on REE and trace elements from several Cu-Au deposits along the lower Yangtze metallogenic valley, central-southern Anhui Province

The Yangtze Valley was one of the most important metallogenic regions during the Jurassic-Cretaceous period in East China, where more than 200 polymetallic Cu-Fe-Au, Mo, Zn, Pb, Ag deposits have been found. Trace elements were chemically analyzed and the relevant data were collected from literature for the Yanshanian (Mesozoic) igneous rocks which have close relationship with Cu-Au mineralization. Copper mineralization in the lower Yangtze Valley can be divided into three major types: skarn type, porphyry type and volcanic type. The porphyry type is of rare occurrence, such as the Shaxi porphyry copper deposit in the northern part of the lower Yangtze metallogenic valley. This paper focuses on the REE and trace element geochemistry of several Cu-Au deposits along the lower part of Yangtze metallogenic valley in Anhui. The results showed that there are differences in REE distribution for these four types of Cu-Au mineralization, which confine the sources of REE and trace elements as well as other mantle and transitional compatible elements. The results of both REE and trace element geochemical studies showed that these elements with different characteristics have different origins, probably representing different sources of Cu-Au deposits in the deep crust and upper mantle environments. The 40Ar/39Ar dating of one biotite sample gave an age of 131 Ma with a high level of confidence, which represents the age of formation of the Shaxi porphyrite intrusive with porphrytic Cu-Au mineralization, which is consistent with that of the majority of the adjacent acid intrusives with mass Cu-Au mineralization along the Yangtze metallogenic belt in the Yanshanian period (Mesozoic). This is the first attempt to use the high precision method to date the Shaxi porphyrite intrusive.     

SR-XRF analysis of Polytrichum in the Fildes Peninsula,Antarctica

In order to study the element contents and distribution of various mosses collected in the Antarctica, we analyzed the heavy elements of 3 species of Polytri-chum in the Fildes Peninsula, P. alpinum, P. juniperinum and P. alpestre, by synchrotron radiation X-ray fluorescence ( SR-XRF). The result shows that the elements, such as K, Ca, Mn, Fe, Cu, Zn and Sr, are nearly the same in Potytrichum. The peak intensity of K is higher than that of Ca, and the peak intensity of Ca is higher than that of Fe in P. alpinum. In P. juniperinum, the peak intensity of K is higher than that of Ca, and the peak intensity of Ca is close to that of Fe. The peak intensity of K is nearly equal to those of Ca and Fe in P. alpestre. Therefore, the habitats of 3 species of Polytrichum are similar in the Fildes Peninsula. By XRF analyzing of different parts of P. alpestre, we found that the peak intensities of relative concentration of elements are obviously different. The peak intensity of K in apical-bud is the highest in orga     

南极中山站及毗邻地区湖泊与冰雪CODMn研究

在 CHINARE- 1 5考察期间对中山站及毗邻地区的湖泊和冰雪进行了采样。它们的CODMn指数与中国《地面水环境质量标准》相比 ,可分为三类 :一类水质所占比重最大 ,大约为56% ,二类和三类分别为 37%、7%。各类水体的 CODMn指数主要为自然源所贡献 ,人为污染不明显。湖水的 CODMn指数是生物生长状况、有机质含量、盐度和水体氧化还原程度的综合体现 ,新鲜降雪样的 CODMn指数指示了该地区的大气洁净度。     

Sr/Ca,Mg/Ca:珊瑚岛鸟粪沉积的物源指示计*

文章尝试用Sr/Ca,Mg/Ca比值作物源指示计,区分了珊瑚岛屿受到海鸟粪影响的湖泊沉积物中鸟粪、珊瑚砂、植物这几种主要的环境介质对沉积物的相对贡献,据此恢复1800年来西沙群岛东岛海鸟数量变化和植被演化的历史。结果表明,东岛海鸟数量的变化历史可划分为潜伏期、增长期、稳定期和衰退期4个阶段,历史时期东岛海鸟生态系统的建立和发展与岛屿植被的演变有着密切的联系。研究获得的方法和初步结论为进一步开展西沙岛屿海鸟数量变化、植被演化的广泛对比并探讨与气候变化、人类活动的相互联系提供了基础。     

SR-XRF analysis of Polytrichum in the Fildes Peninsula,Antarctica

In order to study the element contents and distribution of various mosses collected in the Antarctica, we analyzed the heavy elements of 3 species of Polytri-chum in the Fildes Peninsula, P. alpinum, P. juniperinum and P. alpestre, by synchrotron radiation X-ray fluorescence ( SR-XRF). The result shows that the elements, such as K, Ca, Mn, Fe, Cu, Zn and Sr, are nearly the same in Potytrichum. The peak intensity of K is higher than that of Ca, and the peak intensity of Ca is higher than that of Fe in P. alpinum. In P. juniperinum, the peak intensity of K is higher than that of Ca, and the peak intensity of Ca is close to that of Fe. The peak intensity of K is nearly equal to those of Ca and Fe in P. alpestre. Therefore, the habitats of 3 species of Polytrichum are similar in the Fildes Peninsula. By XRF analyzing of different parts of P. alpestre, we found that the peak intensities of relative concentration of elements are obviously different. The peak intensity of K in apical-bud is the highest in orga     

南极乔治王岛六种苔藓植物的X荧光分析

在无标样条件下 ,我们利用微束 X荧光分析法对南极乔治王岛的 6种苔藓植物的叶和茎进行重元素分析。它们是 :Andreaea regularis,Bryum muehlenbeckii,Drepanocladus uncinatus,Brachythecium subpilosum,Tortula saxiola,Ditrichum austro- georgicum。研究结果发现 ,不同苔藓植物对各种不同重元素的吸收能力不同 ,即使是同一种植物 ,叶和茎中的重元素成分也有差异。在 6种苔藓中 ,Andreaea regularis体内的重元素种类最少 ,但其对 Fe有较强的吸收。由于南极环境条件优越 ,在苔藓植物体内 ,尚未发现大量有毒重金属元素的存在