扬子板块的地壳演化与地层对比

扬子板块是在古元古－新太古宙的古陆核基础上发展演化而成。吕梁运动以前，以川中微型陆块为主体的若干个小型古陆块组成向北西突出的牛轭形陆块带。中元古宙在牛轭形陆块带的东西两侧形成海沟岛弧系，沉积一套弧前及弧后的优地槽和旰地槽建造。１０－１１亿年时的东川运动使沟弧系褶皱回返，固结为陆新元古宙早期产生大陆裂谷，形成五一套裂谷建造，晋宁运动使扬子板块整体固结新元古宙晚发育山前磨拉建造、冰碛层及碳酸盐盖层。全     

鲜水河断裂带的构造大地测量

利用短边GPS点阵、短基线标石阵和精密激光测距 ,在与鲜水河断裂带的断层破裂带垂直的剖面上和构造盆地内进行构造大地测量 ,获得了断层软弱带和断层蠕变带上的最佳形变分布。综合利用相关地学成果和理论 ,揭示了构造形变所隐含的动力学信息 ,识别了断层应变带、塑性流变带和主断面在地面的分布范围。用外围GPS远场联测成果探讨了该断裂带的驱动力机制 ,匡正了其“左旋”运动和现今活动速度的含义。最后 ,评估了该断裂的地震活动趋势     

中小震近场地震动估计中地震动衰减关系的适用性分析

核工程场地设计基准地震动确定中涉及弥散地震的地震动估计，这导致中小震近场地震动估计成为被关注的研究课题。本文基于一些中小震近场地震动记录资料，分析和探讨了国内外多种地震动衰减关系对中小震近场地震动估计的适用性问题，并结合我国几个核工程地震问题研究工作的实践对中小震近场地震动衰减关系确定的思路和原则提出了建议。     

陕西关中盆地大气降水同位素研究

大气降水作为地下水的主要补给源之一,它是自然界水循环过程中的一个重要环节.查明大气降水中同位素分布特征及其影响因素,不仅有助于定性或定量地研究地下水的起源和形成等问题,更有助于揭示"三水"转化关系.根据全球大气降水同位素观测网 1985～1993 年大气降水氢氧同位素资料并结合所采集样品的分析结果对陕西关中盆地大气降水环境同位素特征、变化规律及其影响因素进行了探讨,建立了西安地区雨水线,为地下水的起源及运移研究奠定了基础.     

Delft3D在鳌江口外平阳咀海域流场模拟中的应用

Dem3D是以FLOW水动力模块为主体，建立在Navier-Stokes方程的基础上，由一系列模块组成的模型软件，可以对水流、波浪、泥沙、水质、地貌等建立二、三维模型。本文介绍了Delft3D数值模拟软件的程序模块及数值理论基本方程．对鳌江口外平阳咀海域的流场进行了模拟研究。研究表明：计算结果与实测结果吻合较好，能够较好地反映该海区真实的流场情况．可以为工程研究提供基本的流场背景。     

Transport and deposition of suspended particles in saturated porous media: hydrodynamic effect

A laboratory study was undertaken to determine the transport and deposition rate of suspended particles in columns of saturated porous media (gravel and glass beads), where the porous media were subjected to steady-state flow. Silt particles with a mode of 14 μm diameter (used as the suspended particles) and fluorescein (as the conservative tracer) were injected into the columns in short pulses. The breakthrough curves were competently described with the analytical solution of a convection–dispersion equation with a first-order deposition rate. The experiments were performed using different flow rates. The suspended particle size distribution, the porous media, and the flow rates themselves were the main factors retained in this study to investigate the mechanisms governing the transport and deposition kinetics in detail. The results showed the existence of a flow rate, beyond which suspended particles travel faster than the conservative tracer. A decrease of the deposition rate of suspended particles beyond a critical flow velocity was also observed. Such behaviour led to consideration of the couple hydrodynamic-gravity forces at high flow rates. As the hydrodynamic force increases, particle deposition rates are reduced due to the effect of hydrodynamic forces inhibiting the deposition.     

Study on Uncertainties of Seismicity Parameters b and ν_4 in Seismic Statistical Zones

For several seismic statistical zones in North China,the key factors causing uncertainties in the important seismicity parameters b and ν_4 and the features of their uncertainties are discussed in this paper.The magnitude of uncertainty is also analyzed.It can be seen that the key influencing factors are statistical period,methods of processing statistical samples,lower limit magnitude and the annual average occurrence ratio of large earthquakes.The variation ranges of b and ν_4 in the Tancheng-Lujiang zone are as high as 0.2 and 1.4 respectively,which are similar to those in the Fenwei zone.They are much smaller however in the Hebei zone because of its sufficient statistical samples.     

增强型道格拉斯—普克压缩算法的设计与实现

本文首先论述了经典的道格拉斯—普克压缩算法，分析将其应用于多边形边界数据压缩所造成的图形失真现象，提出了一种增强型道格拉斯—普克压缩算法，并用实际的MapInfo矢量数据来检核该算法的可靠性。     

2—（2，3，5—三氮唑偶氮）—1，8—二羟基—3，6—萘二磺酸与钴的显色反应及应用

介绍了新水溶性显色剂 2 - ( 2 ,3,5 -三氮唑偶氮 ) - 1 ,8-二羟基 - 3,6-萘二磺酸与钴的显色反应及应用 ,建立了测定钴的新方法。在 pH 9.9的Na2 B4O7 NaOH缓冲液中该试剂与钴形成 1∶1蓝色稳定络合物 ,λmax为 5 88.8nm ,Co的质量浓度在 0～ 1 .0mg/L内符合比尔定律 ,表观摩尔吸光系数为 3.46× 1 0 4 L·mol- 1 ·cm- 1 。所拟方法用于环境水样及维生素B1 2 注射液中的微量钴测定 ,结果与原子吸收法相符 ,5次测定的RSD <1 %。     

如何控制数字地下地形图的空间占用

数字地形图的数据量的大小不但取决于采点密谋，而且也受AUTOCAD中的某些操作的影响。