黔西南高砷煤的分布及地球化学特征研究

根据野外地质特征结合中子活化成分分析结果,探讨了黔西南高砷煤的分布特征、影响因素和某些地球化学特征。高砷煤严格受构造（褶皱和断层）、地层（二叠系龙潭组）、沉积相（海陆交互相）的控制,分布于平行北斜长轴的断层两侧,愈靠近断层面砷的含量愈高。砷在煤中的分布极不均匀,即使同一煤层变化也极大。在时空关系与元素组合上高砷煤与区内卡林型金矿密切相关。     

1977-1989中国冰川地质研究的新取向

中国的传统冰川地质学研究是同李四光的名字紧密相连的。１９７７年以后，现代沉积学的原理和方法在中国冰川地质学的研究中得到了广泛的应用。中国西部的自然条件易于形成突发性的泥石流。区别冰川沉积物和泥石流沉积物在沉积学上的异同是冰川地层学研究中的关键问题。解决有关中国西部冰川扩张的次数和范围等重大问题，有待于冰川地层学和冰川地貌学新手段的综合运用。     

全球寒武系年代地层再划分的新建议

介绍最近提交国际地层委员会寒武系分会的全球寒武系年代地层划分方案 ,划分为 4个统级单位和 10个阶级单位 ,同时提出划分芙蓉统的两个新点位 ,即球接子类三叶虫 Agnostote orientalis和 L otagnostusamericanus的首现。     

Single zircon evaporation ages: Evidence for the Mesoproterozoic crust in the southeastern Nigerian basement complex

The Ukwortung area of the Obudu Plateau exposes high-grade metamorphic rocks of upper amphibolite to granulite facies. Zircon grains from three locations of Southwest Obudu Plateau were dated by the Pb-Pb dating method. This single zircon radiometric dating method confirms the occurrence of Mesoproterozoic crust in the southeastern Nigeria basement complex. The pyroxene gneiss (granulite facies) sample from Biereberi near Ukpe yielded a mean age of 2061.4±0.4 Ma, suggesting the presence of Paleoproterozoic crust. The combined 207Pb/206Pb ratios from the garnet-biotite gneiss in the area gave a mean age of 1794.4±0.4 Ma. This further confirms the pres-ence of Paleoproterozoic crustal components within the Obudu Plateau. The Mesoproterozoic (1548.8±0.5 Ma) and Neoproterozoic (619.8±0.9 Ma) ages were obtained from two populations of zircon grains from the leucogranite in Okordem, Southwest Obudu. These "signatures" collaborate the occurrence of Mesoproterozoic ages in the Afar region and Cameroon basements along with the southeastern Nigerian basement complex, constituting the major portion of the West Central African mobile belt. The zircon age of 1794.4±0.4 Ma may probably be the maximum depositional age of the meta-sediment (garnet-biotite gneiss) and the age of 1548.8±0.5 Ma may be interpreted as the time of emplacement of the granitoid. The Neoproterozoic age (619.8±0.9 Ma) probably records the metamorphic event that was prevalent during the Pan-African period and thus affected the area.     

Multifractal Simulation of GeochemicalMap Patterns

INTRODUCTIONThe mathematical modeling of geochemical data continuesto present an important challenge to earth scientists. Basically,the available data are 2-dimensional realizations of 3dimensional patterns, which are the results of one or more genetic processes that usually are poorly understood. It may bedifficult to project from the observations into the rock mass. Inthis paper, multifractal modeling is advocated as a methodologyto characterize geochemical patterns. If a geochemical pa…     

SHARE Asia自动气象站网络：喜马拉雅山—喀喇昆仑山地区气候研究的一个必要组成部分

Ev K2 CNR SHARE Asia计划的目标就是建立一个沿喜马拉雅山—喀喇昆仑山脉的监测网络，为气象学和气候研究提供参数，特别是为季风变化、大气化学、冰川学、高海拔湖沼学和古湖沼学等研究，同时也为准确地确定地球表面坐标。SHARE Asia 计划的一个特殊的目的是发展一套完整的测量系统，以满足不断进步的环境与地球科学；促进当地的技术升级和建设的能力。 就像WMO CEOP 和UNEP ABC一样，SHARE Asia 气象—气候及大气化学观测站已经成为重要的国际科学计划的一部分。     

Geochemistry of metasedimentary rocks of the Sonakhan and Mahakoshal greenstone belts,Central India:Implications for paleoweathering,paleogeography and mechanisms of greenstone belt development

A comparative study of the Precambrian Sonakhan(SGB) and Mahakoshal(MGB) greenstones belts of Central India has been undertaken to decipher their provenance,paleoweathering,paleogeography,and tectonics.As compared to the Upper Continental Crust(UCC),the MGB samples are enriched while the SGB samples are depleted in mafic elements indicating the presence of mafic rocks in the source of the MGB.This is complemented by the Ni–Cr diagram.The REE concentrations,LREE fractionated patterns and negative...     

Analysis of an Ensemble of High-Resolution WRF Simulations for the Rapid Intensification of Super Typhoon Rammasun(2014)

Diagnostics are presented from an ensemble of high-resolution forecasts that differed markedly in their predictions of the rapid intensification(RI) of Typhoon Rammasun. We show that the basic difference stems from subtle differences in initializations of(a) 500-850-h Pa environmental winds, and(b) midlevel moisture and ventilation. We then describe how these differences impact on the evolving convective organization, storm structure, and the timing of RI. As expected,ascent, diabatic heating an...