大气电探测技术

雷电信息的快速瞬变特性给对它的测量研究带来了困难。近年来由于微电子学技术等的进展,促进了对雷电的观测研究。根据雷电产生的电磁辐射、光辐射、冲击波和雷声等物理效应,可研制各种探测仪器。而雷电产生的电磁效应,往往成为雷电探测的有效信息,我们的仪器大部份是依据电磁场变化的主要特征原理来研制的。闪电时云中电位梯度发生快速变化,如果闪电与测站的距离L远大于雷雨云的尺度和高度,则任一瞬间t的地面垂直电场F(t)表示为     

亚洲的扩张挤压构造——从简单蜡泥实验得出的新见解

利用单边封闭的蜡泥塑料来进行平面压陷实验以帮助我们去了解东亚限定的陆间形变和走向—滑动断层的演化。一些大型左旋走向—滑动断层曾不断活化,主体上是同时的。实验显示印度向亚洲插入曾经旋转了(≈25°),并且在碰撞的前二、三千万年里沿红河左旋断层使印度支那向东南挤压了(≈800公里)。该过程能说明南中国海在晚中新世前张开的原因。挤压构造北移,促动阿尔金塔格断层成为第二条主要的左旋断层,并使华南向东移动数百公里。事件发生后,印度支那保持顺时针转动(多达40°),而红河和它南面的走向—滑动断层则作反方向运动。莫圭盆地和安达曼海的张开(直到现在)看来也是挤压的简单运动结果。中国东北部和云南现代裂谷可看出类似于南中国海和安达曼海的初期。若以我们实验为指南,像泰国海湾(暹罗湾——译者)等沉积盆地的其它第三纪构造现象可说明是碰撞的结果。实验还预示有一个重要的左旋走向滑动断层和裂谷系将扩展穿过天山、蒙古和贝加尔而延至鄂霍茨克海。     

单点交会(插点)坐标计算的一个通式

本文应用矢量代数的理论推导了交会定点坐标计算的通式。在通式的基础上,利用待定点坐标与已知数据和观测数据间的函数关系,推出了各种交会定点方法相应的计算公式。     

工程控制测量用三角测量观测平差方法

讨论典型工程控制测量中三角测量和观测方程平差的方法，这个方法的优点与传统的条件法比较通过两个检验网成果的验算来叙述。     

武夷山北麓东乡瑶圩—弋阳周潭变质岩区的构造特征

本文较系统地介绍了武夷山北麓瑶圩－周潭变质岩区基本构造特征，指出了该区周潭杂岩可能属华夏古陆组成部分，沙畈组及其以上地层应属不整合于其上的新元古代－寒武纪沉积地层，它们在变形变质特征上具有一定的差异性，并对其构造演化作了初步探讨。     

西奈东部Bir Zreir菱形地堑的成因

Bir Zreir菱形地堑,位于西奈东部.此地堑在三维空间上出露良好.前寒武纪结晶基底和上覆显生宇沉积物之间的近水平状不整合面,基底侵入体的接触面和早中新世的基性岩脉体系可使人们非常精确地填绘局部构造,确定沿断层的垂直和水平位移.用标准的“拉开(Pullapart)模式”对Bir Zreir菱形地堑预测的垂直离距比观察到的大3到6倍.根据Bir Zreir地块发生旋转运动而建立的另一种模式,与野外的证据更为接近。本文推论:地堑的形状和大小由初始断层的格局所决定;后期构造运动使地堑的最终形状相对没有什么变化.Bir Zreir地块的旋转是南北向断层的左旋位移和其走向变为北北东以及区域上东西向拉张的综合结果.本文所提出的模式,不需要沿斜向断层(diagonal fault)有一个类如“拉开”那样大而深的张裂(gap)。     

陕西南部主要成矿带控矿条件初步分析(续)

四、“勉略宁”铁、铅、锌、金、银、镍、石棉成矿带位于本省西南部勉县、略阳、宁强一带,北界略阳—褒城断裂.南抵阳平关—洋县断裂。大地构造位置隶属于摩天岭加里东褶皱带。(一)地质概况出露地层主要是中上元古界碧口群变质火山—沉积岩和震旦系碎屑岩—碳酸盐岩.它们都是我省重要的含矿地层。侵入岩主要有两期.一为加里东期超基性岩和基性岩、一为华力     

石陨石化学全分析

石陨石通常是由镁铁质硅酸盐、硫化物、铁镍纹石所组成。本文以硅酸盐岩石全分析方案为基础,结合原子吸收快速,准确的特点,拟出了石陨石全分析的方案。应用比方案对湖北随县陨石雨样品的分析取得了满意的结果。 仪器与试剂 日立220A型分光光度计 日立180-70型原子吸收分光光度计 试剂均为优级纯或分析纯 实验部分 一、样品加工 石陨石的组成与地球上一般的岩石很不相同,因此制样过程中应作特殊处理。过去常将样品分选为磁性矿物和非磁性矿物,分析时按比例称取磁性和非磁性两部分样品或者是分别分析磁性和非磁性两部分样品。资料介绍了不经分选的样品加工方     

Quantitative measurement of channel-block hydraulic interactions by experimental saturation of a large, natural, fissured rock mass

The hydrodynamic behavior of fissured media relies on the relationships between a few very conductive fractures (channels) and the remaining low-conductivity fractures and matrix (blocks). We made a quantitative measurement of those relationships and their effect on water drainage and storage in a 19,000 m3 natural reservoir consisting of karstified limestones. This reservoir was artificially saturated with water by closing a water gate on the main outlet during a varying time (delta t) fixed by the operator. The water gate was completely or partly closed until the water pressure reached a particular specified value. If the water gate was left completely closed long enough, the water pressure was fixed by the elevation of temporary outlets at the site boundaries. The water elevation within the reservoir was monitored by means of pressure cells located on single fractures representative of the bedding plane and the two families of fractures of the massif network. The comparison of pressure variations with the network geometry allows us to identify a typical double permeability characterized by a few very conductive channels along 10 vertical faults. These channels limit blocks consisting of low-conductivity bedding planes and a rather impervious matrix. Depending on the closure interval, delta t, of the water gate, the total volume of water stored in the reservoir can vary from 0.8 m3 (delta t = 5 minutes) to 18.6 m3 (delta t = 2 days). Such a variance of storage versus closure time is explained by the reservoir's double permeability that is characterized by blocks that saturate much more slowly than channels. If plotted versus time, this injected volume fits a power relationship, according to the saturation state of the blocks. In less than 34 minutes, storage is close to zero in the blocks and to 1.6 to 2 m3 in the channels. For closing times shorter than 1 hour, only 1% of the volume that flows in the channels is stored into the blocks. Depending on the water pressure and for a given delta t = 3000 minutes, the volume of water stored is controlled by the geometry of the joint network and of the aquifer boundaries. Such an experiment shows that the flow is concentrated in about 10% of the fractured network (channels). The water storage that takes place in the 90% remaining fractures (blocks) depends mainly on time during which pressure remains high into the 10% channels. The accurate modeling of such typical double-permeability media needs a careful study of the geometry of the channels whose narrowings modify the flow and induce dam effects that maintain a high pressure gradient with surrounding blocks.     

国家气象中心预报业务流程初探

以国家气象中心的业务为例，分析了当前气象预报服务的业务能力与需求的差距，指出了进行气象预报服务业务流程的变革的必要性，探索了进行业务流程设计调整的具体内容和步骤，提出了强化服务能力，深化预报业务，拓展评估产品的改革思路，以及建立服务、预报和评估互动的无缝隙预报服务流程的设想。