景观生态学的学科整合与中国景观生态学展望

分析了国际景观生态学三个相互联系的研究领域,指出了各领域的主要研究内容。在阐述景观生态学三个发展阶段的基础上,指出了景观生态学学科发展的基本趋势。从三个方向的整合、时空尺度的匹配、多学科的整合和三个群体的整合4?个方面,阐述了走向整合的景观生态学的发展方向和途径。介绍了当前国际景观生态学研究的热点问题和热点地区,并就中国景观生态学发展的方向和任务提出了作者的看法。     

基于三重震相波形非线性反演的俯冲带410-km间断面起伏研究

利用NECESSArray宽频带地震台阵记录的P波三重震相波形资料,采用遗传算法,对千岛俯冲板块内部及附近410-km间断面的结构进行了非线性反演.其中,选取了发生在俯冲带的发震时刻为2009年10月10日21时24分(GMT时间)震级为M_w5.9的地震;其三重震相的射线回折点处射线路径的方向与俯冲板块的走向大致一致,克服了间断面在俯冲板块内部沿俯冲方向起伏剧烈、不易识别的困难,设计以震中为顶点、方位角范围分别为275°～280°、269°～274°、264°～266°的北、中、南三个扇形区域,用于研究410-km间断面逐渐靠近俯冲板块直至处在其中的起伏情况;"先对齐、后反演"的具体计算方案极大地减小了浅部结构不确定性对反演结果的影响;同时,整体归一化策略充分利用了台阵的振幅信息,有效地加强了对深部结构的约束.反演结果显示,"410-km间断面"在北区抬升了10～20 km,在中区抬升了20～30 km,在南区抬升了60～70 km,与橄榄石-瓦兹利石平衡态相变界面的矿物物理学预测结果一致;其波速跃变在北区为10%,在中区为10%,在南区为7%.扣除了前人在层析成...     

STUDY OF PHYSICAL MECHANISM FOR ACTIVE AND BREAK PHASES OF SOUTH ASIAN MONSOON

Using a low-order spectral model derived from the equatorial equilibrium model, possible physical mechanisms are interpreted by the theory of multiple equilibria states for the active and break phases of the South Asian Monsoon, with consideration of the effects of heating by cumulus heating and cooling by radiation. The result shows that the South Asian Monsoon is active when the cumulus convection intensifies (or the radiation cooling weakens). the monsoon breaks when the convection weakens (or the cooling intensifies). It is consistent with the hypothesis of cloud-radiation by Krishnamurti et al.     

晋蒙交界孔兹岩系熔体参与变质反应的结构特征及其动力学意义

晋蒙交界孔兹岩系变质反应结构与矿物相转变机制研究结果表明,在麻粒岩相变质及其与之相伴随的重熔作用过程中,存在一类特殊的有熔体参与的变质反应,即未熔矿物与熔体之间的反应。结合天然块状岩石高温高压实验,确定研究区孔兹岩系熔体参与变质反应如下：①２Ｇｔ＋（９ＳｉＯ２＋４Ａｌ２Ｏ３）熔体＝３Ｃｒｄ;②Ｇｔ＋（２ＳｉＯ２＋２Ａｌ２Ｏ３）熔体＝Ｓｐ＋Ｃｒｄ;③２Ｇｔ＋（３ＳｉＯ２）熔体＝２Ｏｐｘ＋Ｃｒｄ;④１４Ｇｔ＋（２５ＳｉＯ２＋４Ｈ２Ｏ）熔体＝４Ｃｕｍ＋７Ｃｒｄ。这类熔体参与变质反应不仅受控于温压条件,而且与寄主岩石脱水熔融、长英质矿物部分熔融存在密切成因关系。该项理论与实验研究对于深化变质反应理论、探讨孔兹岩系矿物相转变成因机制及其动力学过程有着重要的意义。     

云贵湖泊现代沉积物早期成岩过程中微量重金属地球化学行为研究

云贵湖泊现代沉积物早期成岩过程中微量重金属地球化学行为研究＠马英军￥中国科学院地球化学研究所湖泊沉积物,孔隙水,微量重金属,早期成岩作用,地球化学相云贵湖泊现代沉积物早期成岩过程中微量重金属地球化学行为研究马英军（中国科学院地球化学研究所,贵阳５５０００２...     

The influence of the structural distribution and hardness of mineral phases on the size and shape of rock drilling particles

Abstract

Rock drilling is a significant activity widely used in the exploration of marine mineral resources and offshore civil engineering such as marine mining, petroleum and deep-water drilling. The characteristics of size and shape of particles produced during rock drilling influence drilling efficiency and energy consumption. We report a series of drilling experiments on sandstone, limestone and shale to systematically examine particle size distribution and shape and correlate these with original rock structure and composition. Correlations are established via metrics of particle size distribution, average circularity and specific surface area. Impact breakage and contact abrasion of individual particles during rock drilling are the main mechanisms controlling particle size and shape. Impact breakage is controlled by the structural distribution of mineral phases, while contact abrasion is principally related to the hardness of mineral phases. The particle size distribution is affected by the structural distribution of mineral phases. The average circularity of the drilling particles is mainly controlled by the hardness of mineral phases. The specific surface area of rock drilling particles is determined by both structural distribution and hardness of mineral phases – with homogeneous structure and low average hardness of the phases reducing the resulting specific surface area of the drilling products.     

First-principles simulation of high-pressure polymorphs in MgAl<Subscript>2</Subscript>O<Subscript>4</Subscript>

We have used density functional theory to investigate the stability of MgAl₂O₄ polymorphs under pressure. Our results can reasonably explain the transition sequence of MgAl₂O₄ polymorphs observed in previous experiments. The spinel phase (stable at ambient conditions) dissociates into periclase and corundum at 14 GPa. With increasing pressure, a phase change from the two oxides to a calcium-ferrite phase occurs, and finally transforms to a calcium-titanate phase at 68 GPa. The calcium-titanate phase is stable up to at least 150 GPa, and we did not observe a stability field for a hexagonal phase or periclase + Rh₂O₃(II)-type Al₂O₃. The bulk moduli of the phases calculated in this study are in good agreement with those measured in high-pressure experiments. Our results differ from those of a previous study using similar methods. We attribute this inconsistency to an incomplete optimization of a cell shape and ionic positions at high pressures in the previous calculations.     

Melt impregnation phases in the mantle section of the Ślęża ophiolite (SW Poland)

The ultramafic member of the Variscan Ślęża Ophiolite (SW Poland) consists of heavily serpentinised, refractory harzburgites. Those located down to 1.5 km below paleo-Moho contain scarce grains or aggregates of olivine, clinopyroxene and spinel. Non-serpentine phases occur in various assemblages: M1—olivine (Fo 90.2–91.0%, NiO 0.38–0.47 wt.%) and rounded or amaeboidal aluminous chromite, rimmed by Al poor chromite and magnetite; M2—olivine (Fo 90.5–91.5, NiO 0.32–0.44 wt.%), olivine with magnetite inclusions (Fo 87.1–92.5, NiO 0.01–0.68 wt.%), rounded, cleavaged clinopyroxene I (Mg# 91.1–93.2, Al₂O₃ 3.00–4.00 wt.%, Cr₂O₃ 1.00–1.40 wt.%) and elongated clinopyroxene II and clinopyroxene from symplectites with magnetite (Mg# = 92.2–94.1, Al₂O₃ 2.20–3.20 wt.% and Cr₂O₃ 0.80–1.20 wt.%). Clinopyroxene is depleted in REEs relative to chondrite. The M3 assemblage consists of intergrown olivine (Fo 90.8–92.7, NiO 0.20–0.38 wt.%) and clinopyroxene (Mg# = 96.0–98.1, Al₂O₃ 0.00–1.00 wt.% and Cr₂O₃ 0.20–0.60 wt.%).The M1 assemblage contains chromite which records greenschist-facies metamorphism. Textural relationships and chemical composition of clinopyroxene occurring in the M2 assemblage are similar to those formed in oceanic spreading centres by LREE depleted basaltic melt percolation. Olivine occurring in M1 assemblage and part of that from M2 have composition typical of residual olivine from the abyssal harzburgites and of olivine formed in those rocks by melt percolation. The olivine with magnetite inclusions (M2 assemblage) and that from M3 record later deserpentinization event, which supposedly produced also M3 clinopyroxene. The non-serpentine phases from the Ślęża ophiolite mantle member, albeit very poorly preserved, document depleted basaltic melt percolation in the Variscan oceanic spreading centre.     

福州市经济发展阶段划分及其特征分析

福州——福建的省会城市,是祖国大陆离台湾省最近的省会中心城市,也是中国市场化程度和对外开放度较高的地区,是中国首批14个沿海港口开放城市之一．本研究选取1978—2009年代表福州市经济总量水平、经济结构、制度水平、创新水平与医疗水平等方面的部分指标进行了统计分析,采用熵值法和最优分割法进行发展阶段划分．从分析结果可以看出,1978年以来福州市的经济发展可分5个阶段：第一阶段为1978--1981年,即恢复阶段;第二阶段为1982--1984年,即经济调整阶段;第三阶段为1985--1992年,即经济快速增长阶段;第四阶段为1993--2004年,即调整改革与平稳增长阶段;第五阶段为2005年以后,这一阶段为向更高一级工业化阶段迈进和经济腾飞阶段．     

长春台不同类型地震的震相特征分析

通过对长春台CTS-1型宽频带地震计记录到的不同震中距及不同类型地震的波形进行分析,分别得出CTS-1型地震计所记录到的不同震中距及不同类型地震的震相特征。结果表明,每个类型的地震都各有自己的震相特征。