河北兴隆M111稀有金属花岗岩体地质和岩石学特征

本文报道了河北燕山地区一个稀有金属花岗岩体的地质特征、岩石学、矿物学和岩石化学特征.这个两次侵入形成的复式岩体,Rb-Sr同位素年龄171Ma。造岩矿物为石英、钠长石、微斜长石、含锂云母。化学成分铝过饱和富钠偏碱性.发育良好的岩性垂直分带,岩石结构、矿物和化学成分均呈规律性的变化.岩浆成分向富钠富稀碱富挥发分的方向分异演化导至Nb、Ta、Li、Be、Rb、Cs等稀有金属矿化。     

Age and generation of Fogang granite batholith and Wushi diorite-hornblende gabbro body

Fogang granitic batholith, the largest Late Mesozoic batholith in the Nanling region, has an exposure area of ca. 6000 km2. Wushi diorite-hornblende gabbro body is situated at the northeast part of the ba- tholith. Both the granitic batholith main body and the diorite-hornblende gabbro body belong to high-K calc alkaline series. Compared with the granitic main body, the Wushi body has lower Si (49%―55%), higher Fe, Mg, Ca, lower REE, less depletion of Eu, Ba, P, Ti, and obvious depletion of Zr, Hf. Zircon LA-ICP-MS dating and the mineral-whole rock isochron dating reveal that Fogang granitic main body and Wushi body were generated simultaneously at ca. 160 Ma. The Fogang granitic main body has high (87Sr/86Sr)i ratios (0.70871―0.71570) and low εNd(t) values (?5.11―?8.93), suggesting the origins of the granitic rocks from crustal materials. Their Nd two-stage model ages range from 1.37―1.68 Ga. The Sr and Nd isotopic compositions and the Nd model ages of the granitic rocks may suggest that the giant Fogang granitic main body was generated from a heterogeneous source, with participation of mantle component. Wushi diorite-hornblende gabbro is an unusual intermediate-basic magmatic rock series, with high (87Sr/86Sr)i ratios (0.71256―0.71318) and low εNd(t) values (?7.32―?7.92), which was possibly formed through mixing between the mantle-derived juvenile basaltic magma and the magma produced by the dehydration melting of lower crustal basaltic rocks.     

堪察加半岛东北地区发生8.0级地震

据中国台网测定,2006年4月21日7时25分3.0秒.在堪察加半岛东北地区(61.0°N,167.2°E)发生8.0级地震.美国地质调查局和日本气象局估计此次地震约为7.7级.     

Spatial distribution and sources identification of polycyclic aromatic hydrocarbons in Wolong Lake,Northeast China

The aquatic ecosystem maybe significantly affected by polycyclic aromatic hydrocarbons(PAHs) released from fresh water sediments. In order to protect biodiversity, the spatial distribution and sources of PAHs in the sediment of Wolong Lake in Northeast China were studied. A total of 17 surface sediment samples were collected and 12 PAHs were analyzed. The results were as follows. The concentration of total PAHs(TPAHs) ranged between 1412.9 μg/kg and 3948.3 μg/kg(dry weight). Indeno [1, 2, 3-c, d] pyrene was the dominant contaminant which accounted for 87%–98% of TPAHs. Diagnostic ratios of PAHs and principal component analysis showed that biomass combustion and vehicle emissions were likely to be the dominant sources of PAHs in the sediment. PAHs can be considered safe in the context of environmental and human health protection, based on the overall toxicity. Individual PAHs were positively correlated with total organic carbons. These results will be helpful to control PAHs and protect the aquatic ecosystem in the lake.     

Study of shear stress in laminar pipe flow using entropy concept

In fluid mechanics, the shear stress is calculated from the frictional force caused by viscosity and fluctuating velocity. Shear stress equations are used widely because of their simplicity. On the other hand, they have a critical limitation of requiring an energy gradient, which is generally difficult to estimate in practice. In particular, measuring the shear stress and velocity gradient on the boundary layer is difficult. The point velocity throughout the entire cross section is needed to calculate the velocity gradient. This study proposes the shear stress distribution equations for laminar flow based on entropy theory using the mean velocity and entropy coefficient. The proposed equations were compared with the measured shear stress distribution using Nikuradse’s data. The results revealed a correlation coefficient of approximately 0.99, indicating that the proposed method fits the Nikuradse’s data. Therefore, the shear stress distribution can be estimated easily and accurately using the proposed equations, which can be used in future for the management and design of a water pipeline.     

与其导数具有分担值的全纯函数的正规族

证明了一个区域上的全纯函数族是正规的。如果任意的两人相互判别的有限非零值为族中任意函数及其一阶导数在该区域中的ＣＭ分担值 。     

固结度平方根法计算公式的理论证明

自从太沙基在实验基础上提出固结度与时间因数计算的平方根法公式以来,其在工程中发挥了重大的作用,但其理论上的证明一直未见报导。以误差函数为基础,对平方根法计算公式进行了理论上的论证,得到了平方根法计算公式的原型,并与前人级数公式的计算结果进行了对比,两者吻合良好。     

汶川地震余震序列的地震各向异性初步分析

2008年5月12日,在四川龙门山断裂带上发生了8.0级大地震,根据中国地震台网中心的地震目录,震源深度为14km处,属于浅源构造地震.汶川地震序列是主震余震型.截至到2008年10月,已发生了3万余次连续余震.北东走向的龙门山断裂带位于青藏高原东缘,是由3条断裂构成,自西向东分别是龙门山后山断裂,龙门山主中央断裂,龙门山山前断裂.龙门山断裂带是一条以逆冲为主,走滑为辅的大型断裂带.     

1990-2015年喜马拉雅山东段中国和不丹边境地区冰川变化研究

利用Landsat影像,EDM影像等数据资料,使用遥感图像处理及目视解译方法提取了喜马拉雅山东段中国与不丹边境地区冰川从1990—2015年4期边界,研究其与气温降水变化关系,并选取特定冰川,对其表面流速进行估算。研究表明：1990—2015年,该地区冰川退缩速率达0.43%·a^-1,并且冰川年退缩率逐渐增大,表明冰川消融速度逐渐加快。该时段内,气温呈现明显上升趋势,导致了冰川的快速消融。通过对冰川表面流速的估算,得出中国与不丹边境地区研究选取的冰前湖对冰川流速具有促进作用,加速冰川消融。