新西兰韦斯特兰省南阿尔卑斯山铜金热液体系

新西兰的南阿尔卑斯山是一个现在还在上升的山脉,在阿尔比尼断层附近显示出地热异常,阿尔比尼断层是澳大利亚板块和太平洋板块的分界线。在这个上升带中出现了强烈的热液运动,这种热液运动导致了石英脉中的金属矿化。金的矿化限于绿片岩相的岩石中,而阿尔比尼断层附近的角闪岩相岩石中年轻的石英脉中则富含铜。地下上升的热液和下渗的大气降水溶液之间的相互作用控制着这个复杂的热液体系中金属的搬运活动和沉淀过程。变质热液已与石墨片岩围岩相平衡,并且相对被还原,大气水的渗入和混合增加了氧的活动性而降低了硫的活动性。大气水在下渗过程中被氧化,但温度上升,溶解了一些铜。当这种液体变成还原状态时,溶解的铜便沉淀出来。因此,这个热液体系的中间部分,铜的含量是逐渐增加的,特别是在阿尔比尼断层附近的强烈破碎渗透性较好的岩石中。     

Dynamics of phosphorus and nitrogen through litter fall and decomposition in a tropical mangrove forest

Distribution, dynamics and mass budget of phosphorus and nitrogen in a red mangrove forest were studied in the Potengi mangrove forest in northern Brazil (lat. 5 degrees 42' and 5 degrees 53'S, long. 35 degrees 5' and 35 degrees 25'W). Tidal hydrology, net primary productivity, leaf litter decomposition rate and standing stock of leaf litter in a red mangrove forest were measured. The results showed that the main reservoir for total P and total N was the sediment with 309 kg ha(-1) and 4619 kg ha(-1) (77% and 95% of the total P and N content in the mangrove forest), respectively, for the two elements. Total P and total N in Rhizophora mangle trees accounted for 145+/-14 kg ha(-1) and 216+/-23 kg ha(-1) (23% and 5% of the total P and N in the mangrove forest). The estimated average export rates for P and N through leaf litter are 0.5 kg ha(-1)yr(-1) and 1.6 kg ha(-1)yr(-1) respectively. Our measurements support previous results in concluding that mangrove forests efficiently retain P and N.     

Heterogeneities in glaciofluvial deposits using an example from new hampshire

The strong influence of subsurface heterogeneity on contaminant migration and in situ remediation calls for an improved understanding of its origins and more efficient methods of characterization. Accordingly, an outcrop study of physical and chemical heterogeneity was conducted in a glaciofluvial deposit in Deerfield, New Hampshire, in order to uncover processes controlling the spatial variation of sediment properties and evaluate the extent to which geologic information can be used to characterize the observed variation. The results indicate that physical and chemical properties at the Deerfield site have distinctly different spatial correlation structures. Lithologic facies explain 31% to 60% of the variation in permeability, dithionite citrate (DC)-extractable manganese, and DC-extractable aluminum. Lithofacies bounding surfaces do not separate regions of significantly different DC-extractable iron; instead, 49% of its variation is explained by sediment color. Color also accounts for 34% of the variation in DC-extractable aluminum and 60% of the variation in DC-extractable manganese. Strong relationships with sediment facies and/or color enable detailed mapping of permeability, extractable iron, and extractable manganese. Differences in the geometries of iron and manganese enrichment, petrographic observations, and scanning electron microscope analyses indicate that (hydr)oxide grain coatings originated from the postdepositional weathering of biotite and garnet, coupled with local, redox-driven redistribution of the liberated iron and manganese. The findings suggest that lithofacies and color information can aid the characterization and modeling of heterogeneity at similar carbon-poor glaciofluvial sites.     

用微机系统改进浅层高分辨率地震反射方法

记录设备动态范围的增在和数据处理软，硬件成本的下降使得地震反射方法在环境场地划分等地质目标体推断上成为一种卓有效的方法。近年来，使用便携微机地震仪采用数据并采用普通８０４８６ＰＣ机处理浅层地震反射数据，以环境，地质技术和地下水等单方面的应用表明了该方法解决关键地质科学问题的可行性。     

极地气象科学计划及将来的任务

本文简要地叙述了极地气候和通常笼统称为极地气象学研究的特征。列出了与极地气象委员会(ICPM)一起对南北极感兴趣的组织,并对他们的活动作了简要的描述。确定了当前研究的主要领域为极地的海-冰-大气相互作用、冰盖上地面风的季节变化特征、天气与动力气象学和气候学的研究、大气化学和大气成分、云和古气候。在此基础上,给出了极地气象学将来的主要任务。