Phytoplankton structure, composition and production in saline water-bodies in the Lower Amu Dar'ya

Phytoplankton and its production in water-bodies of the lower Amu Dar'ya were investigated in 1984–1989. The structure and functional nature of the phytoplankton in the water-bodies studied were analogous to those of the littoral zone of eutrophic lakes, considering hydrological and hydrochemical conditions. The very high average annual P/B ratios (453–582) are considered as regional features, namely high light intensity and prolonged light period, the salinity usual for saline waters under anthropogenic influence, the frequent and discrete income of nutrients in drainage water and from sediments.     

测井评价稠油层等级的新方法

从测井信息中提取油和水的重量百分比,最能反映稠油层质量的特征.用油和水的重量百分比评价稠油层等级,是一种新概念.测井评价稠油层等级的新方法,就是根据这一新概念建立的.本文论述了新方法的物理基础,建立了测井评价稠油层等级的数学公式,并且给出了评价法则和应用范例.     

不同震级范围的地震频度和频度比

讨论了云南地区不同震级范围的小震频度在强震前的时间进程曲线,发现在介质比较破碎地区,震级偏小的地震频度显示出较明显的强震前孕震系统的非线性阶段,而在介质比较完整的地区,则震级偏大的地震频度反应较明显。为此,引入了频度比的概念,结果表明,强震孕震区的频度比表现为在强震前2—4年,持续增加或持续降低,在强震前1—2年,呈(增加后)降低或(降低后)增加的异常变化,曲线形态出现拐点。对频度比在实际预报工作中的预报能力,也进行了讨     

粘弹性拉张型地震破裂过程的解析解

本文应用包括地壳破裂发震过程中具有激发及衰减的非线性Rayleigh阻尼,用Voigt粘弹性模型表示地壳,它能更全面地反映地壳介质分子之间的内摩擦造成的粘滞性阻尼,在数学方法上,用解非线性问题解析法的摄动理论结合动坐标的富氏级数,把问题的非线性控制方程组化为各阶线性化的控制方程组后,再简化为标准的Mathieu方程构成的耦连方程组,再用WKBJ方法,给出其在稳定区域的近似解,从而得出了问题的解析解。     

山西历史强震震中和沉降中心的关系

根据对历史地震震中和山西断陷带内沉降中心的研究,发现该带内的强震震中与沉降中心有很好的对应关系。以现有的资料为基础,统计了各沉降中心内第四系与新生界的比值(Q/Kz)。结果表明,强震的发生与沉降中心的 Q/Kz值有一定的对应规律。根据这一结果,近一步讨论了512年7 1/2级地震的震中位置。     

岩浆分离结晶作用的微量元素广义初始比值计算方法

本文提出了一种如何从分异的派生岩浆追溯和反演演化前的原生岩浆的微量元素初始比值的方法。据分离结晶方程logaC_1~q=k·loga C_1~p b,得广义初始比值:C_0~q/(C_0~p)~k=a~b。它与已公认的原生岩浆的判别参数如~(87)Sr/~(86)初始比、δ~(18)O‰、SI、Mg′值及微量元素丰度等有极好的一致性。并将这种方法应用于两个实例,得出大宁花岗闪长岩及其暗色微粒包体分属壳源和幔源;五大连池富钾火山岩的原生岩浆为白榴苦橄碧玄岩浆,而其中的超镁铁质岩包体则是分离结晶的火成堆晶体。     

Temporal and spacial analysis of regional composite nodal plane solutions for small earthquakes

A method is proposed in this paper for the analysis of temporal and spatial characteristics of composite nodal plane solutions for small earthquakes. With this method, the interested region is devided into small areas according to the geological features of the region. As an example, 107 composite nodal plane solutions are calculated for the adjoining region of Shaxi, Hebei and Neimenggu. The temporal and spatial characteristics of the variations of the solution parameters before and after the great Tangshan main earthquake in 1976 have been analysed and some interesting results are obtained. The Chinese version of this paper appeared in the Chinese edition ofActa Seismlogica Sinica,13, 9–20, 1991.