塞尔维亚蒂莫克铜金矿集区典型矿床地质特征

特提斯成矿带是全球三大成矿带之一,阿普塞尼（Apuseni）−巴纳特（Banat）−蒂莫克（Timok）−斯雷德诺戈里斯基（Srednogorie）岩浆成矿带（ABTS多金属成矿带）位于特提斯成矿带西缘,由阿普塞尼–巴纳特铁铜铅锌矿集区、蒂莫克铜金矿集区和斯雷德诺戈里斯基铜金矿集区组成,成矿作用主要与晚白垩世钙碱性岩浆活动有关。塞尔维亚蒂莫克铜金矿集区作为ABTS多金属成矿带经济意义巨大的矿集区之一,总结该地区矿床地质特征及成矿规律对下一步的找矿勘查具有重要指导意义。综述了蒂莫克铜金矿集区及其典型矿床的地质特征,总结了矿集区成矿规律与动力学背景。蒂莫克铜金矿集区典型矿床形成时代集中在88 ~ 78 Ma之间,成矿作用历时10 Ma左右,矿集区内成矿作用时代呈现出由东向西逐渐年轻的趋势。矿集区中典型矿床类型主要为斑岩型（如马伊丹佩克矿床、克里韦利矿床和瓦利亚斯特尔茨矿床）和高硫化浅成低温热液-斑岩型（如博尔矿床和丘卡卢佩吉矿床）,这些矿床以铜金矿化为主。矿床类型、矿化特征及矿体埋深存在的差异可能与区域上新生代右旋构造在矿集区形成的逆冲推覆构造及成矿后不均匀剥蚀有关。根据矿集区典型矿床的矿化类型及矿体埋深海拔标高的变化趋势,认为矿集区北部—西北部和丘卡卢佩吉矿床东南部仍具有一定的找矿潜力。     

EXPERIMENTAL STUDY ON FALL VELOCITY OF NON-UNIFORM SEDIMENT IN FLOWING WATER

I INTRODUCTIONThe settlement of particles in fluid has been studied in many fields such as hydraulics, metallurgy andchemistry since the middle of 19 century because of its great importance. Although the settlement ofsingle particle and group settling velocity of uniform particles in still water are relatively well-studied, yetthe settlement of non-uniform particles in flowing water lacks understanding. For instance, Cunningham(1910), Richardson (1954) and Batchelor (1972), have obtained…     

Fractal generation of surface area of porous media

Many natural porous geological rock formations, as well as engineered porous structures, have fractal properties, i.e., they are self-similar over several length scales. While there have been many experimental and theoretical studies on how to quantify a fractal porous medium and on how to determine its fractal dimension, the numerical generation of a fractal pore structure with predefined statistical and scaling properties is somewhat scarcer. In the present paper a new numerical method for generating a three-dimensional porous medium with any desired probability density function (PDF) and autocorrelation function (ACF) is presented. The well-known Turning Bands Method (TBM) is modified to generate three-dimensional synthetic isotropic and anisotropic porous media with a Gaussian PDF and exponential-decay ACF. Porous media with other PDF's and ACF's are constructed with a nonlinear, iterative PDF and ACF transformation, whereby the arbitrary PDF is converted to an equivalent Gaussian PDF which is then simulated with the classical TBM. Employing a new method for the estimation of the surface area for a given porosity, the fractal dimensions of the surface area of the synthetic porous media generated in this way are then measured by classical fractal perimeter/area relationships. Different 3D porous media are simulated by varying the porosity and the correlation structure of the random field. The performance of the simulations is evaluated by checking the ensemble statistics, the mean, variance and ACF of the simulated random field. For a porous medium with Gaussian PDF, an average fractal dimension of approximately 2.76 is obtained which is in the range of values of actually measured fractal dimensions of molecular surfaces. For a porous medium with a non-Gaussian quadratic PDF the calculated fractal dimension appears to be consistently higher and averages 2.82. The results also show that the fractal dimension is neither strongly dependent of the porosity nor of the degree of anisotropy assumed.     

Characteristics of China’s oil and gas pool formation in latest geological history

The structural activities took place extensively in the Asia continent during the Cenozoic era owing to the strong continent-to-continent collision and continuous compression between the India Plate and the Eurasia Plate. Huang Jiqing called such structural activities Himalayan movement. China’s sedimentary basins developed and took shape mainly during the Himalayan movement period. It is also the main period for formation and development of the oil and gas reservoirs. Of 366 large and medium-sized oil and gas fields currently found in China, 212 reservoirs were formed in the Neogene-Quaternary period. The proportion is as high as 68.2%. The oil and gas migration and accumulation in the latest geological period, which were controlled by the times, properties, styles and strength of the Himalayan movement, took place mainly in eight regions, such as the low uplift area of Bohai Sea, the onshore faulted sag area of Bohai Bay, anticlinorium zone in Daqing, the foreland fold-and-thrust belt in West China, the tilted structural zone in West China, the cratonic palaeohigh in the Tarim Basin, the zone of fault and fold belt in the East Sichuan Basin, and the biological gas zone in the East Qaidam Basin. The oil and gas pool formations in those regions have their own characteristics. With the great potential and broad prospect, those regions are the main exploration areas in China in the future.     

Geochemical Characteristics and Significance of Basalt in the Hongshiyan Pb-Zn-Cu Polymetallic Deposit in Southeastern Yunnan Province

<正>1 Introduction Southeast Yunnan is the convergent place of the Yangtze,Indochina blocks(Xu Wei,et al.2008).The Hongshiyan Pb-Zn-Cu polymetallic deposit is located in Wenshan Prefecture,Yunnan Province.It is a typical large sized VMS-type deposit discovered in recent years.The major ore minerals are sphalerite,galena,chalcopyrite ect.     

Drought characteristics of Henan province in 1961-2013 based on Standardized Precipitation Evapotranspiration Index

Drought is one of the most complex natural hazards affecting agriculture, water resources, natural ecosystems, and society. The negative societal consequences of drought include severe economic losses, famine, epidemics, and land degradation. However, few studies have analyzed the complexity of drought characteristics, both at multiple time scales and with variations in evapotranspiration. In this study, drought occurrences were quantified using a new drought index, the Standardized Precipitation Evapotranspiration Index (SPEI), based on observed data of monthly mean temperature and precipitation from 1961 to 2013 in Henan province, central China. Based on the SPEI values of each weather station in the study, the frequency and severity of meteorological droughts were computed, and the monthly, seasonal, and annual drought frequency and intensity over a 53-year period were analyzed. The spatial and temporal evolution, intensity, and the primary causes of drought occurrence in Henan were revealed. The results showed that the SPEI values effectively reflected the spatial and temporal pattern of drought occurrence. As the time scale decreased, the amplitude of the SPEI increased and droughts became more frequent. Since 1961, drought has occurred at the annual, seasonal, and monthly scales, and the occurrence of drought has increased. However, regional distribution has been uneven. The highest drought frequency, 35%, was observed in the Zhoukou region, while the lowest value, ~26%, was measured in central and western Henan. The most severe droughts occurred in the spring and summer, followed by autumn. Annually, wide-ranging droughts occurred in 1966–1968, 1998–2000, and 2011–2013. The drought intensity showed higher values in north and west Henan, and lower values in its east and south. The maximum drought intensity value was recorded in Anyang, and the minimum occurred in Zhumadian, at 22.18% and 16.60%, respectively. The factors with the greatest influence on drought occurrence are increasing temperatures, the Eurasian atmospheric circulation patterns, and the El Niño effect.     

南极乔治王岛环境质量现状调查

本文以１９９２／１９９３年度中国第九次南极考察期间对南极乔治王岛的表土、地衣、苔藓等样品的分析资料为基础，研究探讨了８种无机重金属元素、５种有机污染物的浓度水平。其结果表明，重金属在三种环境样品中的含量分布存在着明显的差异；地衣、苔藓两种植物呈现对不同重金属元素的不同富集能力；∑６６６、∑ＤＤＴ和ＰＣＢｓ及油的沾污亦很明显。本文还对污染物质的来源、南极环境样品历次调查分析的结果以及世界部分地区的背景水平进行了讨论和比较     

论东亚地区期货市场的发展趋势

本文从东亚地区期货市场发展的基本特征出发，针对期货市场发展中存在的主要问题，分析了它未来的发展趋势。认为其发展将趋于集中化，主核心将日渐清晰，走彼此协同的合作发展道路。     

δ~(18)O, δD and d-excess signatures of ground ice in permafrost in the Beiluhe Basin on the Qinghai-Tibet Plateau,China

In this paper, stable isotope(δ~(18)O, δD) investigations were completed in ground ice from a deep borehole in the Beiluhe Basin on northern Qinghai-Tibet Plateau to unravel the isotopic variations of ground ice and their possible source water. The δ~(18)O and δD of ground ice show distinctive characteristics compared with precipitation and surface water. The near-surface ground ice is highly enriched in heavier isotopes(δ~(18)O and δD), which were gradually depleted from top to bottom along the profile. It is suggestive of different origin and ice formation process. According to isotopic variations, the ice profile was divided into three sections: the near-surface ground ice at 2.5 m is frozen by the active-layer water which suffered evaporation. It is possible that ground ice between 3 and 4.2 m is recharged by the infiltration of snowmelt. From 5 to 6 m, the ground ice show complex origin and formation processes. Isotopic variations from 6 to 11.1 m and 20.55 m indicate different replenishment water. The calculated slope of freezing line(S=6.4) is larger than the experimental value(5.76), and is suggestive of complex origin and formation process of ground ice.