现代湖泊沉积物中磁性矿物的研究及其环境意义

通过固城湖沉积物中高分辨率的岩石磁学取样及其实验研究，取得了环境磁学参数及各种磁参数的比值随深度的变化曲线，结合其他气候指标和同位素年龄结果，表明湖泊沉积中磁参数及其比值的变化能与末次晚冰期以来的古气候变化很好地相对应，尤其是在４．００ｍ和１２．０３ｍ的气候转折点上，沉积物中环境磁参数及其比值同样出现明显的变化，有力地说明沉积物中磁参数及其比值能很好地记录湖泊沉积物沉积时的古气候变化，并且可用来认识古环境突变的界线．     

监测网参数的可估性

监测网是一类特殊的控制网。本文根据可估定义，讨论了监测网中一些参数的可估问题，得到位移向量为不可估量，变形参数为可估量，此结论对于监测网的数据处理和设计具有较大的指导作用。     

GPS相对定位中的双差新方法

本文首先用附加虚拟观测值的方法导出一种新的多测站相对定位的双差算子方法，然后，证明了该算子方法与现有算子方法的等价性，最后论述了该方法的计算过程并给出有关结果。     

LiCl的Pitzer参数的优化

由于锂盐的重要性和氯化锂在电解质中的特殊性，ＬｉＣｌ和Ｃｉ２ＳＯ４的热力学问题一直被化学家所重视。Ｐｉｔｚｅｒ在其关于电解质的系列论文中给出的ＬｉＣｌ参数，适用的最大浓度仅为６ｍ。１９８８年Ｈｅｅ—Ｔａ１Ｋｉｍ等给出了适用于浓度直达饱和的参数。本文根据多年来我们对含锂盐体系的研究结果，经多种处理获得了ＬｉＣｌ和Ｌｉ２ＳＯ４的新Ｐｉｔａｅｒ参数。发现对于０—６ｍ和６ｍ一饱和不同浓度范围，ＬｉＣｌ的Ｐｉｔｚｅｒ参数截然不同。所获得的参数对于溶解度计算特别有意义。作者还从ＬｉＣｌ溶液的结构讨论了造成参数不同的原因。     

Magnetic studies on the remanence carriers in igneous rocks of different ages

A critical study on the type of the magnetic grains, both in composition and domain state, in rocks of different ages has been carried out. One simple, fast and non-destructive test, which can provide useful information on the nature of the magnetic grains in freshly collected samples, seems to be the ratio of susceptibilities at 77 and 300 K. This ratio, termed relative susceptibility, ranges from 0·1, for samples containing 70% ulvospinel bearing titanomagnetite (TM70) to 1·50 for cation deficient magnetite bearing ones. The results indicate that the value of 0·1 for TM70 is not greatly affected even if some amount of TM80, which is nonmagnetic at 300 K, is present in a rock sample. However, the coercive force at 77 K will increase considerably for such a sample. The effects of mixed compositions and domain states of magnetic grains on the overall behaviour of basalts are discussed.     

Scaling of peak ground motions from digital recordings of small earthquakes at Campi Flegrei,southern Italy

The dependence of peak ground acceleration and velocity on seismic moment is studied for a set of small earthquakes (0.7<M _L<3.2) recorded digitally at distances of a few km in the Campi Flegrei volcanic area near Naples, Italy, during the ground uplift episode of 1982–1984. Numerical simulations, using the -square spectral model with constant stress drop and ane ^–kf high frequency decay, fit well both the velocity and acceleration data for an averagek=0.015. The observed ground motions in the 1–24 Hz frequency band appear to consist of radiation from simple sources modified only slightly by attenuation effects. Moreover, the scaling of peak values agrees closely with those determined in nonvolcanic areas, once the difference in stress drop is taken into account.     

Estimation of hypocentral parameters of local earthquakes when crustal layers have constantP-velocities and dipping interfaces

The paper describes an algorithm for estimating the hypocentral coordinates and origin time of local earthquakes when the wave speed model to be employed is a layered one with dipping interfaces. A constrained least-squared error problem has been solved using the penalty function approach, in conjunction with the sequential unconstrained optimization technique of Fiacco and McCormick. Joint confidence intervals for the computed parameters are estimated using the approach of Bard for nonlinear problems. These results show that when a hypocentre lies outside the array of recording stations and head waves from a dipping interface are involved, then its inclination must be taken into account for dip angles exceeding 5°.     

某些岩石动态性质的初步试验研究

测定和研究与岩石实际破碎过程有关的动载特性,对解决工程中如何有效地破碎岩石和防止岩石破坏两问题很有必要。为此,笔者对几种常见的岩石用“冲击应力脉冲法”进行了试验,并与岩石声波仪测出的结果进行了对比;讨论了岩石动载特性参数,并认为它们对岩石可钻性和爆破性的研究有一定的参考价值。     

Semigroup solutions to stochastic unsteady groundwater flow subject to random parameters

Two methods for the solution of partial differential equations (PDE) for the general case of random in time physical parameters are presented and their application to the solution of unsteady regional groundwater flow equations are illustrated. The first method is the semigroup approach which directly offers a solution without resorting to closure approximations (hierarchy techniques), perturbation techniques, or Montecarlo simulation techniques. The semigroup approach can also handle the general stochastic problem when randomness also appears as initial conditions, boundary conditions or forcing terms. The second method is an approximation scheme to obtain the semigroup solution in complex cases and permits the solution of equations with more than one random coefficient.