第29届IASPEI大会岩石圈结构,动力学过程和各向异性专题概述

第２９届ＩＡＳＰＥＩ大会于１９９７年８月１８～２８日在希腊塞萨洛尼基举行,来自世界各地的约１０００名科学家出席了本届大会。该文较详细地介绍了本届大会中有关“岩石圈结构、动力学过程和各向异性”专题（Ｓ１１）的学术交流情况及各国学者在该专题的研究方面所取得的进展。     

Secularization in the Netherlands in its historical and geographical dimensions

The Netherlands is one of the most secularized countries in the western world. The aim of this paper is to put the secularization process in both historical and geographical perspective. As a mass process secularization started in the last quarter of the nineteenth century and accelerated from the sixties of this century onwards. The first concentrations of non-denominationalism could be found in the (Protestant) countryside of Friesland and Groningen as a consequence of profound social cleavages. Then, the big cities in the west took part in the process and more recently even the Catholic areas were affected due to the cultural revolution of the sixties and early seventies. Two counterforces were analysed: a religious revival within the Protestant community and the increasing proportion of Muslims and Hindus as a consequence of immigration and high fertility levels. This revised version was published online in August 2006 with corrections to the Cover Date.     

Accuracy of elastic finite differences in smooth media

The accuracy of finite-difference schemes of the 2nd and 4th order in 2-D and 3-D regular rectangular grids is studied. The method of designing the schemes and estimating their accuracy is proposed. The paper is devoted to the point schemes, expressed in terms of the discretized (point) values of the wave field and material parameters. Only the common schemes applicable in smooth parts of seismic models, outside structural interfaces, are taken into account. Finite differences at structural interfaces are studied elsewhere.The inaccuracy of finite-difference schemes is governed, above all, by the error in the phase velocity, caused by discretization. This error is estimated for several finite-difference schemes. It is explicitly dependent on the direction of propagation and on wave polarization. The maximum phase-velocity error over all directions of propagation enables the accuracy of the individual schemes to be appreciated in order to select the best one. The proposed approach is general and applicable to other finite-difference schemes, for example, of the 6th and higher orders.     

Un « point chaud » sous le système du Rift syrien : données pétrologiques complémentaires sur les enclaves du volcanisme récent

Ultrabasic xenoliths (pyroxenites, lherzolites, harzburgites) in recent (Neogene–Quaternary) volcanoes have been studied in three localities within Syria: Jubates (North), Mhailbeh (Center), Tel Thannoun (South). P–T conditions of mineral equilibration have been estimated by pyroxene thermometry (temperature) and maximum CO₂ density in primary inclusions (minimum pressure). Pyroxenites equilibrate at significantly higher conditions (T about 1200 °C, P>15 kbar) than lherzolites and harzburgites (900<T<1100 °C, P between 10 and 15 kbar). All are within the spinel lherzolite field, whereas Cretaceous xenoliths originate within the garnet lherzolite field. To cite this article: A. Bilal, F. Sheleh, C. R. Geoscience 336 (2004).     

新世纪的广州市中心商务区建设

中心商务区的建设是城市经济水平的折影。中心商务区的3个发展演化阶段：前现代主义的中心商务区、现代主义的中心商务区、后现代主义的中心商务区。从发展战略角度出发，广州市以珠江新城为中心的中心商务区应致力于后现代主义的中心商务区建设，与传统中心商务区形成系列化、互补协调的中心商务区系统。根据广州市建设后现代主义中心商务区的条件并参照国内外中心商务区建设的经验，广州以珠江新城为中心的中心商务区建设应在增强自身吸引力的同时，导入后现代主义开发意识，以适合新世纪新经济、新文化等新形势的发展需要。     

History of the Photogrammetric Society

The Photogrammetric Society was formed in 1952. The Council of the Society considered that the twentieth anniversary was a good point at which to record the events which led to its formation and the significant occasions and decisions which have taken place since 1952. Consequently, Paul Lamboit was invited to compile this History. He has placed the birth and development of the society within the national and international photogrammetric context and his record of the deliberations which took place between 1947 and 1952 will be of particular interest to historians of our subject.
This account was first published in a limited edition in 1971. Sufficient interest has since been expressed to prompt a wider circulation through publication in the Photogrammetric Record .
The author served the Society continuously in several official capacities from 1953 to 1969 and he was elected to Honorary Membership in 1969.     

辽宁省防震减灾“九五”重点项目实施概况及建设成果

“九五”期间，辽宁省地震局按照中国地震局的统一部署，应用先进的数字技术、网络技术和计算机技术，对原有的前兆与地震观测的模拟技术系统进行了改造，新建了辽宁省地震信息网络系统和防震减灾指挥中心，这是辽宁省第一次这样大规模地对防震减灾技术系统进行建设和改造。本文对“九五”重点项目的任务、技术系统构成及建设成果进行了阐述。     

共轭伸展褶劈理夹角的定量解析

９０ 年代初以来,中国地质学者先后在浙、皖、赣、湘的“板溪群”及震旦系中发现了古生代的生物化石。因此,再次将“板溪群”是否是前震旦纪的一个变质地层单位、江南古陆是否存在以及华南大地构造格局是否需要重新厘定等问题提了出来。１９９３ 年笔者于赣东北蛇绿混杂岩带内的“双桥山群”岩块中,首次发现了含晚古生代的放射虫硅质岩。１９９６ 年又在该混杂岩带多处的“双桥山群”岩块和“下震旦统志棠组”中找到了含晚古生代的放射虫硅质岩,还首次在“登山群拔竹坑组”中发现了早古生代的几丁虫化石。经数年野外多次观察和对室内化石鉴定、岩石地球化学测试结果以及岩石学特征的综合分析表明,所发现的含晚古生代放射虫硅质岩及其岩石组合是一套洋盆深水相沉积;登山群拔竹坑组,是早古生代的一套浅水陆棚 深水陆棚 半深海相沉积。结合同行学者在邻区“板溪群”研究方面取得的新成果,笔者认为：“板溪群”不是前震旦纪的一个变质地层单位,而是一个复杂的构造岩带,江南古陆是不存在的,华南从早古生代到中生代早期还经历了一次洋盆演化过程,现在的构造格局是印支运动奠定的     

面向网络新闻的爬虫开发与热点新闻事件分析

Python平台开发了网络新闻爬虫,通过实验对比常用的网页数据获取方法,本文提出一种适合新闻网页的解析方式,克服了获取动态网页时源码不完整、单一方法解析网页效率低下等弊端,满足了新闻网页抓取、解析、结构化和入库存储等需求。并将新浪新闻中心作为网络新闻数据采集的目标,分析发现新浪新闻近几年的发展情况。此外,利用词频统计等手段对十九大会议新闻进行分析,直观地反映了十九大的核心人物、关键党派、热点话题变化等重要信息。     

过去千年中国不同区域干湿的多尺度变化特征评估

依据近年发表的新成果,对中国过去千年干湿的年至百年尺度变化特征进行了总结梳理与对比分析,综合评估了20世纪干湿变幅的历史地位。主要结论是：① 根据历史文献记载重建的东中部各区干湿序列在1400年以后均达高信度,但其前因存在记录缺失,仅有半数时段的重建结果达高信度。在东北及内蒙古东部,根据不同地点湖沼沉积物记录揭示的区域干湿百年尺度变化特征在多数时段不一致。在西部的黄土高原、河西走廊、新疆中北部、青藏高原东北部和东南部等地区,利用不同地点树轮资料重建的干湿序列显示的干湿变化特征在区内一致性高。② 过去千年中国各地干湿变化均存在显著的年际、年代际和百年尺度周期。其中准2.5 a、60~80 a和110~120 a等尺度的周期为所有地区共有;3.5~5.0 a、20~35 a等尺度周期则主要发生在东北、东中部地区、黄土高原和青藏高原;而准45 a周期则只发生在东北和东中部地区（均超过90%信度水平）;各区域间的干湿变化位相并不同步。③ 尽管已发现青藏高原东北部20世纪很可能是过去3000 a最湿的世纪之一,但其他大多数区域的重建结果显示：20世纪的干湿变幅在年代际尺度上均未超出其前各个时段的变率范围。