中亚地区矿产资源勘查开发方向

概要地介绍了中亚地区的构造分区特点、优势矿产资源和主要成矿时期。在区域成矿分析的基础上,强调围绕大规模成矿作用进行地质过程解析的重要性,更好地为资源潜力评价和勘查开发选区提供依据。     

The Geographical Distribution of Mental Disorder in Denmark 1971–1990: A Study of First Admission Rates

Geografisk Tidsskrift, Danish Journal of Geography 97: 132–142, 1997.

In the period 1971–90 the first admission rate to Danish psychiatric hospitals and wards decreased by approximately 45%. This might reflect the similar decrease in number of available psychiatric beds. Generally, the decrease of first admission rates was larger in the metropolitan area than in the rest of the country. Consequently, the disparity in admission rates between town and country was reduced. Number of available beds has gained increasing importance as a predictor of variations between counties and municipalities whereas the importance of distance to hospital and degree of urbanization has declined. As regards socio-demographic variables special importance should be attached to variables for social aid and the employment rate in the social and health sector. However, it is generally difficult to determine whether regional variations are due to differences in treatment facilities or morbidity differences. From a disaggregate analysis it will appear that the diagnoses schizophrenia and alcoholism are especially related to low status areas whereas a connection with social status regarding neuroses and manic-depressive psychoses is less obvious.     

库车坳陷复杂高陡构造地震成像研究

复杂构造地震成像主要取决于叠前地震数据品质、偏移速度可靠性和偏移算子成像精度. 库车坳陷异常复杂的近地表条件导致极低信噪比的地震采集数据. 该区逆冲推覆高陡构造刺穿盐体大面积分布, 盐层厚度变化大、顶底面形态复杂, 盐下断裂带破碎、小断块发育, 形成异常复杂的地震成像问题. 本文重点研究三个关键环节:(1)精细的叠前地震预处理研究: 根据该区地震地质复杂性和地震资料特征, 采用一些新的方法技术和技术组合从振幅与时移的大、中、小尺度变化三个层次来解决资料信噪比问题, 重建深部反射信号; (2)三级偏移速度分析研究:利用库车坳陷盐刺穿逆冲推覆构造建模理论及变速成图配套技术解决叠前时间偏移速度场时深转换问题,利用井约束低频速度地震迭代反演技术解决连井层速度场与偏移速度场的融合问题,实现从DMO速度分析、叠前时间偏移速度分析到叠前深度偏移速度分析的有机衔接,建立拓扑结构相对保持的叠前深度偏移速度模型;(3)基于退化Fourier偏移算子的半解析波动方程叠前时间和深度偏移研究, 极大地改善了地震偏移过程中高波数波的成像问题. 通过对库车坳陷大北、博孜、却勒、西秋4和西秋10等复杂高陡构造的叠前时间和深度偏移地震成像处理,取得了较好的应用效果.     

贵州矿产资源开发利用现状分析

本文以科学发展观为指导,分析了贵州矿山企业的规模结构、开发布局、矿山的矿种结构、资源综合利用情况和经济类型,以及矿山的地域分布的现状等,指出了存在的主要问题,对今后全省矿业持续健康发展提出了有益的建议。     

福建锦城187Ma花岗岩的发现——对华南沿海早侏罗世构造演化的制约

本文对福建沿海福清地区的锦城花岗岩和牛头尾花岗闪长岩进行了岩石地球化学、锆石U-Pb-Hf同位素分析.LA-ICP-MS锆石U-Pb定年结果显示锦城花岗岩的年龄为187±1Ma,为福建沿海首次发现的早侏罗世岩浆活动;牛头尾花岗岩形成时代为130±1Ma,代表燕山晚期(白垩纪)的一期岩浆活动.锦城花岗岩具有高5iO2、偏碱、高Fe2OT3等特征,为高钾钙碱性系列,岩石相对富集轻稀土,亏损Nb、Ta、Ti等高场强元素,富集Ba、Sr等大离子亲石元素,具高Rb/Sr( 1.31 ～ 1.93)比值及低Rb/Ba(0.26 ～0.29)、Eu/Eu*(0.30 ～0.56)、La/Yb(5.69 ～ 18.39),Sr/Y(2.24 ～2.29)比值,为典型的Ⅰ型花岗岩,且具有火山孤花岗岩的地球化学特征,很可能形成于与俯冲相关的构造背景.牛头尾花岗岩相比锦城花岗岩低SiO2,贫钾,而富镁、钙,属于花岗闪长岩.其更亏损Nb、Ta及富集Ba、Sr,具较低Rb/Sr(0.27)、Rb/Ba(0.09)比值和较高的Eu/Eu*(0.98)、La/Yb( 16.87),Sr/Y( 19.08)比值,同样为具有弧特征的钙碱性Ⅰ型花岗岩,也形成于与大洋俯冲有关的构造背景.锦城花岗岩和年头尾花岗闪长岩具有相似的锆石Hf同位素组成,εHf(t)分别为2.18～4.73和1.25 ～4.15,tDMC均为～ 1.0Ga,表明二者起源于相同的新元古代新生地壳.结合已有的资料,本次研究发现锦城花岗岩与南岭地区同时代岩浆岩( 194 ～ 172Ma)在成因上有密切的联系,暗示古太平洋板决的俯冲很可能自早侏罗世开始.这样,华南古特提斯构造域向古太平洋构造域的转换很可能发生在早侏罗世之前,大致在205 ～ 190Ma期间.     

Temporal relationship between Holocene human occupation and vegetation change along the northwestern margin of the Central African rainforest

This paper discusses the relationship between patterns of human settlements and environmental change during the Holocene along the northwestern margins of the equatorial rain forest of central Africa. Palaeoenvironmental data from high-resolution sediment cores from lacustrine deposits, plant macro-remains from forest soils, and archaeological data are harnessed to discuss the differential impact of climate and/or humans on the central African rain forest. It is shown that climate change impacted the rain forest well before the widespread expansion of human settlements all over the study area.     

Estimation of load reduction factors for clay masonry walls

The in‐plane cyclic behaviour of three types of unreinforced clay masonry was characterized by means of laboratory tests on full‐scale specimens. The masonry walls were assembled with various bonding arrangements (head joints made with mortar pockets, dry head joints with mechanical interlocking, thin‐layer mortar bed joints), which are not yet inserted in seismic codes. Experimental behaviour was modelled with an analytical hysteretic model able to predict lateral load–displacement curves in case of shear failure of the unreinforced walls. According to the experimental results and those of the selected analytical model, parametric study to evaluate the reduction in lateral strength demand produced by non‐linear behaviour in masonry walls, i.e. the load reduction factor was carried out by non‐linear dynamic analyses. The calculated values of the load reduction factor were modest. The differences in values found for the three masonry types, although consistent with them, were not great. This may indicate that, in the ultimate limit state, the type of masonry cannot significantly affect the behaviour of an entire building. Copyright © 2009 John Wiley & Sons, Ltd.     

测井声波时差反演重构技术研究及应用

利用测井声波时差、自然电位和伽玛重构声波时差,分析了以上3种曲线结果对地质体响应方面的机制差异,给出了这些曲线的深度相对移动校正的方法。研究了多条测井曲线去噪的协方差矩阵特征向量滤波方法。在此基础上,利用小波多尺度分解技术进行声波时差曲线重构。在分析这3种测井曲线不同尺度小波分解结果的信号和噪音特点后,利用相邻分解尺度相关滤波技术,对各种曲线的小尺度(高频)分解结果进行滤波处理。为保证重构声波曲线的真实性,深入分析了多曲线、多尺度分解结果的冗余性(相关性)问题;利用特征值技术,对高频多尺度分解分量进行了非相关(正交)分析,最后实现了声波时差曲线的重构,并对重构结果与钻井岩心录井资料进行了对比验证,重构后的声波曲线在区分砂、泥岩性分辨率方面具有明显的提高     

Nonlinear seismic soil–pile–structure interactions: Shaking table tests and FEM analyses

In this paper, a soil–pile–structure model is tested on a shaking table subject to both a sinusoidal wave and the acceleration time history of the scaled 1940 El Centro earthquake. A medium-size river sand is compacted into a 1.7-m-high laminar rectangular tank to form a loose fill with a relative density of 15%. A single-storey steel structure of 2.54 ton is placed on a concrete pile cap, which is connected to the four end-bearing piles. A very distinct pounding phenomenon between soil and pile is observed; and, the acceleration response of the pile cap can be three times larger than that of the structural response. The pounding is due to the development of a gap separation between soil and pile, and the extraordinary large inertia force suffered at the top of the pile also induces cracking in the pile. To explain this observed phenomenon, nonlinear finite element method (FEM) analyses with a nonlinear gap element have been carried out. The spikes in the acceleration response of the pile cap caused by pounding can be modeled adequately by the FEM analyses. The present results suggest that one of the probable causes of pile damages is due to seismic pounding between the laterally compressed soil and the pile near the pile cap level.     

青藏高原西部改则地区大气边界层特征

利用第二次青藏高原大气科学考察试验（TIPEX）改则站大气边界层物理观测资料,着重揭示了该地区边界层结构的观测事实,尤其是近地层风、温、湿特征和土壤温、湿特征。主要结果如下:（1）边界层内风速随高度呈多极值分布,即使在白天混合层内,空气上下混合也较差;（2）边界层内白天温度递减率较大,可达到1.6 ℃/100 m;（3）白天,边界层常出现逆湿现象。