广东麒麟绿钙闪石巨晶的地球化学特征

本文对罕见的幔源绿钙闪石巨晶进行了综合的地球化学分析，主要元素，稀土微量元素和Ｓｒ，Ｎｄ同位素的特征表明；绿钙闪石巨晶是碱性玄武岩浆在地幔条件下的结晶产物；相对于寄主玄武岩，绿钙闪石巨晶均属捕虏晶，它们与共存的橄榄岩包体无成因联系，其形成可能与共存的黑色包体有关。     

成都粘土裂隙成因研究

根据成都粘土中裂隙特征与地质环境条件的分析，提出成都粘土中途中眩要裂隙类型的成因模式，上升剥蚀引起的垂向卸荷作用产生波状水平裂隙，冲沟切割引起的侧向卸荷作用，产生平行斜列隙裂。     

安徽淮河构造变形带及邻近块体现代构造应力场特征

针对安徽省较特殊的构造环境及历史地震分布特点，利用直达波最大振幅比和系统聚类分析方法，在对安徽淮河中游区1974年以来近百个中小地震震源机制反演、聚类及空间合成的基础上，分析了华北断块南缘的安徽淮河构造变形带及邻近块体震源断层滑动方式、构造应力场分布及块体运动方式、应力场随时间变化等。结果显示：淮河构造变形带及其邻近块体上震源断层总体上以近走滑型或斜滑型破裂为主，但倾滑型破裂也占一定比例；该地区构造应力以水平作用为主，但也存在一定的垂向作用。其中淮北和皖中块体仍可能分别向SWW和NEE方向运动，并在淮河构造变形带上产生左旋剪切作用，呈现一定的继承性活动特征；各块(带)上主压应力P轴走向随时间的变化在总体上较为一致，而各时段之间P轴方位存在一定差异，显示安徽淮河中游区受华北和华南应力场的共同作用，但其地震活动可能主要受控于华北应力场。     

Isotopic Characteristics and Key Factors Favoring the Formation of Fuwan Super-large Silver Deposit in Guangdong Province

Rb-Sr isochron age of fluid inclusions in quartz from the Fuwan super-large silver deposit is 68 - 6 Ma, the silver deposit is characterized by high μ values (10.67 - 10.95 ), which are much higher than those of the ore-hosted Paleozoic strata and are close to those of ores hosted in the Proterozoic metamorphic basement in western Guangdong Province. Based on the Pb isotopic characteristics, coupled with much high background silver contents (200-1000ng/g) in the Proterozoic basement and relatively low silver contents in the Paleozoic strata in the region of the Sanshui Basin, it is concluded that the ore-forming material of the super-large silver deposit came mainly from the old basement. The super-large silver deposit related genetically to the intense volcanic activities during the Upper Cretaceous to Eogene. The formation of the Fuwan super-large silver deposit is controlled by the following favorable geological conditions : ( 1 ) The intersection of deep faults and contemporaneous faults at the margin of the Sanshui Basin led to the formation of an excellent structure as passageway for ore fluids; (2) The special ore-hosted rock association forms a ore gathering-trap structure that favors the precipitation of ore; (3) The silver-rich old basement, multi-stage mineralization and multi-episode volcanic activities which constitute a geothermal convection system.     

Seismotectonic environment of occurring the February 3, 1996 Lijiang M=7.0 earthquake, Yunnan Province

Lijiang-Daju fault, the seismogenic fault of the 1996 Lijiang M=7.0 earthquake, can be divided into Lijiang-Yuhu segment in the south and Yuhu-Daju segment in the north. The two segments show clear difference in geological tectonics, but have the similar dynamic features. Both normal dip-slip and sinistral strike-slip coexist on the fault plane. This kind of movement started at the beginning of the Quaternary (2.4～2.5 Ma B.P.). As to the tectonic types, the detachment fault with low angle was developed in the Early Pleistocene and the normal fault with high angle only after the Mid-Pleistocene (0.8 Ma B.P.). Based on the horizontal displacements of gullies and the vertical variance of planation surfaces cross the Lijiang-Daju fault at east piedmont of Yulong-Haba range, the average horizontal and vertical slip rates are calculated. They are 0.84 mm/a and 0.70 mm/a since the Quaternary and 1.56 mm/a and 1.69 mm/a since the Mid-Pleistocene. The movements of the nearly N-S-trending Lijiang-Daju fault are controlled not only by the regional stress field, but also by the variant movement between the Yulong-Haba range and Lijiang basin. The two kinds of dynamic processes form the characteristics of seismotectonic environment of occurring the 1996 Lijiang earthquake.     

Seepage driving effect on deformations of San Fernando dams

In the process of flow deformation of an earth dam, the seepage force inside the dam plays a role as a driving force. The seepage force acts just like the gravitational force in terms of pushing soils away from their original locations after liquefaction is triggered. This paper draws attention to this seepage driving effect by presenting a set of fully coupled finite element analyses on the well-known San Fernando dams, with the objective of evaluating the impact of this seepage effect. The results indicate that while this effect is always there, its practical significance depends on a number of factors. In the case of the upper San Fernando dam, which experienced a significant, but restricted, downstream movement during the 1971 earthquake, the seepage driving effect was indeed significant. On the contrary, for the lower dam, which failed and slid into the upstream reservoir during the same earthquake, this seepage effect was relatively less pronounced. The detailed results of the analyses reveal the likely mechanisms of failure and deformation of the two dams and the likely cause behind the difference between their responses during the earthquake.     

深圳湾公路大桥设计风速的推算

从资料的完整性和合理性、方法的规范性等几方面着手，对深圳湾公路大桥设计风速进行推算。利用深圳市气象站1954～2001年逐年年最大风速资料，通过时距、高度、地形等订正后得到相当于开阔平地上方10 m高度10 min年最大风速48年序列，使之符合建筑抗风指南或规范的要求。再利用极值Ⅰ型计算出不同重现期的基本风速，同时用耿贝尔的参数估算法和修正后的矩法参数估计法计算出不同重现期（200、120、100、60、50、30、10年）的基本风速。研究发现桥位区自动气象站与深圳市气象站最大风速正相关显著，前者是后者的1.1倍，从而可将基本风速外推到桥位区，进一步根据规范将该值放大1.11/2（1.049）倍至海面上，最终得到设计风速。还利用近地层风的指数和对数曲线推算出150 m内每10 m高度层的最大风速。     

应用"极值剔除"和"逐步消空"法建立太原机场11月份辐射大雾预报指标集

本文介绍了利用“极值剔除”和“逐步消空”方法建立太原机场11月份辐射大雾预报指标集的具体过程，并对得出的预报指标进行回报检验，以证实其在业务中的切实可行性。     

甘肃昌马地区寒武纪构造演化探讨

位于北祁连山造山带西段的昌马地区，1：5万东湾、三道湾幅区调在中寒武世地层中发现Leiosphaeridia，Lophosphaeridium，Cymatiosphaera，Retisphaeridium，Synsphaeridium，Multiplicisphaeridium，Retinarites等晚震旦世的藻类化石。据此，笔者将本区中寒武世地层解体为3部分：晚震旦世地层、早寒武世地层和中寒武世黑茨沟组。并对锅底坑蛇绿混杂岩带进行了确认，在此基础上对本区寒武纪构造演化模式作以探讨。     

高速公路沿线暗浜填土的勘察和评价

目前，线路勘探中对浜填土检测不够重视或缺乏有效的方法，使浜填土的处理缺乏针对性，造成不必要的浪费或工程隐患。该文探讨了在线路勘探中暗浜的勘查技术及相应评价与整治方法。