天镇—怀安地区早前寒武纪钾质花岗岩地球化学特征及构造环境

晋冀内蒙古交界地区太古宙怀安杂岩以南发育一条花岗岩带，和怀安杂岩以高压麻粒岩混杂岩带相隔，是该区一个单独的岩石构造单元，规模较大，宽２０多ｋｍ。从山西繁峙白马石经天镇南部向北东一直到宣化西葛峪和二道岭，断续相连。北东东向延伸近２００ｋｍ，延伸方向与区域片麻理和主构造线方向一致。该花岗岩带由众多中小规模花岗岩侵入体和其间残留体组成。大部分花岗岩呈肉红色，以富钾质和含有高压基性麻粒岩包体为特征，许多花岗岩发育片麻构造。岩石学研究表明，大多数花岗岩经历了变质作用，一些花岗岩经历了麻粒岩相变质作用，具有麻粒岩相矿物组合Ｑ＋Ｐｅｒ＋Ｐｌ±Ｇｔ＋Ｂｉ（棕）±Ｈｂ＋Ｍｔ，石榴石、黑云母等矿物的成分显示出麻粒岩相变质的特征。大部分花岗岩都是近低熔花岗岩的组分，并显示某些钙碱性岩系的演化趋势。微量元素组成表现出较大的变化范围，多数花岗岩富Ｋ，Ｒｂ，Ｂａ，贫Ｚｒ，Ｙ，Ｙｂ，部分样品还亏损Ｔｈ，Ｔａ和Ｎｂ，稀土元素从低到高有４种不同的配分型式。这些花岗岩由许多不同类型源岩的部分熔融形成，具有与碰撞型花岗岩相似的常量和微量元素地球化学性质。锆石Ｕ－Ｐｂ一致线年龄为２３７０Ｍａ，指示出这些花岗岩形成于太古宙末期。这条花岗岩带有可能是     

现代黄河三角洲土地利用变化分析

人类对海岸带的开发利用影响着海岸的变迁。土地利用和土地覆被变化可以说是自然与人文过程交叉最为密切的问题，是人地关系的具体体现。通过对黄河三角洲土地利用变化的研究，可了解人为因素对三角洲海岸带的开发利用状况及其对海岸侵蚀的影响。根据1987年和2001年两期卫星遥感图像和2001年野外调查数据，运用地理信息系统方法及数理统计方法，分析了现代黄河三角洲地区1987年至2001年土地利用／覆被的数量变化和空间变化特征；揭示了该地区各类土地利用数量变化的幅度、速度和土地利用空间变化的主要类型；阐明了该区各类土地利用变化的区域特点。该地区土地利用变化速度比整个环渤海地区速度快，草地、滩地和不明地类这3种类型大量减少，其他类型增多。从变化率来看，养殖区、库塘、油田用地增长最快。库塘、海滩养殖区等类型的增加，滨海草地的减少，使海岸侵蚀加剧。     

丽江高美古台址和2m级望远镜项目(英文)

自 1992年起云南天文台开始了在云南省西北部的天文选址。丽江高美古最终被选择作为未来中国地基天文光学观测的新址点。并且 ,在国家科技部 ,云南省政府 ,以及中科院的支持下 ,2m级天文望远镜项目在 2 0 0 0年 12月获得立项。在文中 ,我们简要的介绍了高美古台址的情况 ,并给出了 2 .4m望远镜的详细情况 ,以及其他相关情况。     

内蒙赤峰莲花山金矿田石英脉的红外光谱成矿信息及定量预测

测试了１３０余件含金石英脉及不含金石英脉的红外光谱试样，查明了该区含金石英脉的红外光谱特征，同时配合其它预测含金石英脉的测量方法，提出了该区含金石英脉的预测靶区，经过初步验证，预测基本上是准确的。     

���������ϲ��α������Ĺ�ϵ

?????????????????????????1985??2006?????????????????????α??????????????????????????????????????????????????????????6???????????????????????????????????????????????????????л??????????????5??????????????????     

Characteristics of water exchange in the Luzon Strait during September 2006

The Luzon Strait is the only deep channel that connects the South China Sea(SCS) with the Pacific.The transport through the Luzon Strait is an important process influencing the circulation,heat and water budgets of the SCS.Early observations have suggested that water enters the SCS in winter but water inflow or outflow in summer is quite controversial.On the basis of hydrographic measurements from CTD along 120° E in the Luzon Strait during the period from September 18 to 20 in 2006,the characteristics of t...     

北京市奥运期间气象灾害风险承受与控制能力分析

针对北京市奥运会期间的7种主要气象灾害(雷电、冰雹、大风、高温、暴雨、大雾和霾灾害),建立了气象灾害风险承受能力与风险控制能力评价的指标体系.经过专家评分,获取7种气象灾害的评价指标所对应的分值.利用层次分析法,计算评价指标的权重系数.最后得到7种气象灾害评价指标的加权平均值作为其风险承受能力与风险控制能力系数.利用灾害模数、经济易损模数、生命易损模数3个指标进行北京市奥运期间18个区县空间易损度区划分析.结果表明:北京市奥运会期间,高温灾害和暴雨灾害的风险承受能力与风险控制能力最弱;雷电灾害和大雾灾害的承受与控制能力中等;冰雹灾害和霾灾害较强;大风灾害最强.易损度空间差异分析表明,城区(东城区、西城区、崇文区和宣武区)、朝阳区和海淀区为高易损性区域;丰台区、石景山区、房山区、昌平区、顺义区和大兴区为中易损性区域;门头沟区、通州区、平谷区、怀柔区、密云县和延庆县为低易损性区域.     

A morphological investigation of marine transgression in estuaries

The landscape setting of estuaries varies widely and is an important aspect of determining how they evolve. This paper focusses on alluvial estuaries in river valleys and how they respond to sea level rise. We examine the implications of marine transgression, as a response to sea level rise, where the estuary moves upwards and landwards to maintain its position in the tidal frame (so-called stratigraphic rollover). Here we encapsulate such kinematic movement of the estuary morphology using a ‘morphokinematic’ model, to assess the potential response to sea level rise and sediment supply. The model of the estuary form includes a single convergent channel, intertidal and surrounding floodplains (the valley) and allows the relative importance of the space available for deposition of sediments, the accommodation space, to be investigated as a function of rates of sea level rise and sediment supply. The transgression of the system is determined using a sediment mass balance, taking account of any supply from the river and marine environment. Model results confirm that the transgression distance, measured as the distance the entity moves landward, varies in proportion to the change in accommodation space, which mainly depends on the floodplain area. As the size of the floodplain reduces, the transgression distance is less and the system becomes much more sensitive to changes in the rate of sea level rise or changes in sediment supply. The greater demand for sediment when a floodplain is present results in greater cannibalization of the estuary form (i.e. greater landward movement) to meet the sediment demand. When the floodplain is disconnected from the estuary, the synergistic relationship is lost and the accommodation space increases. The capacity for restoration will depend on the availability of sediment and the prevailing rate of sea level rise.     

火山活动与沉积盆地的形成和演化

我国大陆地壳进入中生代以来,发生了较其他陆壳更为强烈的构造运动,印支,燕山,喜马拉雅运动都是发生在我国大陆地壳以裂陷作用为主的典型运动,在中生代板块构造的特定时代和以裂陷作用主主的构造运动作用下,岩浆活动沿断穿骨石圈和地壳的深断裂发生,上涌至地壳地面形成火山岩带和地层格架中的火山岩层,上涌至地壳内部形成壳内流体相央浆房而成为高导层,火山活动是由中生代生成的太平洋板块和我国大陆地壳俯冲,使大陆地壳深     

A review of advances in China’s flash flood early-warning system

This paper summarizes the main flash flood early-warning systems of America, Europe, Japan, and Taiwan China and discusses their advantages and disadvantages. The latest development in flash flood prevention is also presented. China’s flash flood prevention system involves three stages. Herein, the warning methods and achievements in the first two stages are introduced in detail. Based on the worldwide experience of flash flood early-warning systems, the general research idea of the third stage is proposed from the viewpoint of requirements for flash flood prevention and construction progress of the next stage in China. Real-time dynamic warning systems can be applied to the early-warning platform at four levels (central level, provincial level, municipal level, and county level) . Through this, soil moisture, peak flow, and water level can be calculated in real-time using distributed hydrological models, and then flash flood warning indexes can be computed based on defined thresholds of runoff and water level. A compound warning index (CWI) can be applied to regions where rainfall and water level are measured by simple equipment. In this manner, flash-flood-related factors such as rainfall intensity and antecedent and cumulative rainfall depths can be determined using the CWI method. The proposed methodology for the third stage could support flash flood prevention measures in the 13th 5-Year Plan for Economic and Social Development of the People’s Republic of China (2016–2020). The research achievements will serve as a guidance for flash flood monitoring and warning as well as flood warning in medium and small rivers.