Trap formation of the Kola peninsula

The nepheline syenites and foidolites of the world’s largest Lovozero and Khibiny allkaline massifs contain numerous xenoliths of intercalating olivine basalts, their tuffs, tuffites, and quartzitosandstones that experienced more (in the Khibiny Massif) or less (in the Lovozero Massif) intense thermal-metasomatic transformation. In terms of geological, petrographical, and petrochemical features, the unaltered rocks of the Lovozero Formation can be ascribed to the rocks of the trap formation, while all wealth of the rocks formed during their contact-metasomatic alteration (sekaninaite-anorthoclase, annite-anorthoclase, fayalite-anorthoclase, rutile-freudenbergite-anorthoclase, topaz-andalusite-anorthoclase, and others) was formed due to alkaline metasomatism. The Fourier analysis of the color variation curves for the volcanogenic-sedimentary rocks revealed the identity between bedding of initial tuffs (tuffites) and banding of their fenitized analogues.     

地质剖面图的计算机绘制技术

提出了一种地质剖面的计算机绘制技术－整体平移法，分层平移法，解决了剖面图形处理中两个关键问题，剖面上变倾角，变落差及任意切割交错关系的断层处理和地层曲线间的形态协调问题。     

Simulation of South American wintertime climate with a nesting system

A numerical nesting system is developed to simulate wintertime climate of the eastern South Pacific-South America-western South Atlantic region, and preliminary results are presented. The nesting system consists of a large-scale global atmospheric general circulation model (GCM) and a regional climate model (RCM). The latter is driven at its boundaries by the GCM. The particularity of this nesting system is that the GCM itself has a variable horizontal resolution (stretched grid). Our main purpose is to assess the plausibility of such a technique to improve climate representation over South America. In order to evaluate how this nesting system represents the main features of the regional circulation, several mean fields have been analyzed. The global model, despite its relatively low resolution, could simulate reasonably well the more significant large-scale circulation patterns. The use of the regional model often results in improvements, but not universally. Many of the systematic errors of the global model are also present in the regional model, although the biases tend to be rectified. Our preliminary results suggest that nesting technique is a computationally low-cost alternative for simulating regional climate features. However, additional simulations, parametrizations tuning and further diagnosis are clearly needed to represent local patterns more precisely. Received: 18 February 1999 / Accepted: 31 May 2000     

青海地区强震活动的统计分析及预报探讨

从统计的角度出发，研究了青海地区１９９３年Ｍ≥６强震的发生概率，在此基础上应用非线性最小二乘法拟合的Ｇｏｍｐｅｒｔｚ与Ｌｏｇｉｓｔｉｃ曲线模型以及可公度模型对该区Ｍ≥６．５强震进行了预测探索。结果表明，１９９３年该地区Ｍ≥６强震的发生概率将达到０．７６－０．８７，１９９３－１９９４年有可能发生Ｍ≥６．５强震。     

Images at 20 cm and the Spectrum Index of NGC 2997

We present total intensity maps of the galaxy NGC 2997 at frequencies 1435.1MHz (λ21cm) and 1652.4MHz (λ18cm) observed with the Very Large Array (VLA). The high spatial resolution allows us to distinguish two dominant arms. Using multi-frequency data, we separate the thermal and non-thermal contributions to the radio emission. The thermal emission is about 35% of the total emission at λ3 cm. We use it to estimate a space-averaged thermal     

Statistics of the Instability Strip of β Cephei Stars

We present a study of the β Cephei instability strip based on a sample of 49 stars of this type.After deriving their effective temperatures and luminosities from their observed(B-V),(U-B) colors and parallaxes we find their positions in the HR diagram to be mostly confined to the main sequence,and their masses to lie between 7 M and 30 M.Their distribution on the HR diagram matches well with our previous theoretical instability strip which has an upper bound in the luminosity and rather tight boundaries in the effective temperature.     

用斜率和曲率湿周法推求河道最小生态需水量的比较

1 Introduction With a long term of increasing water demand by industry, agriculture and domestic use along the rivers since the 20th century all over the world, the contradiction between the rational water use and water (ecological) environmental protect…     

发头裸腹溞休眠卵发育的温度因子分析

测定了不同温度下发头裸腹溞(Moina irrasa)体眠卵的孵化时间及孵化率;取最先孵出和过半数孵出的两组数据依莱奥姆积温法则求得种群休眠卵最低临界温度为12.00℃,最低有效积温为441.61℃·h;最低亚致死高温点(即最适温度)为35.16℃,以及最低死亡高温点39.44℃。种群中过半数的临界温度为12.88℃,过半数有效积温为557.10℃·h,过半数的亚致死高温点为35.56℃以及过半数死亡高温点为39.49℃。讨论了这些参数在枝角类集约化培养中休眠卵的有效保存与启用所具有的实践意义。     

江苏——南黄海地区地震活动趋势研究

根据１４９５￣１９９５年地震资料，对江苏－南黄海地区地震活动分期进行了划分，并对本世纪以来两个地震活跃幕以及地震活动趋势进行了详细讨论。基于统计分析方法，给出未来中强地震概率估计，并采用多种方法对未来地震进行了预测探讨。