A DYNAMICAL STUDY OF THE FLOW FIELD IN THE PBL OVER LARGE-SCALE TOPOGRAPHY*

In this paper, the eddy coefficient and the treatment for dividing layers of Estoque's numerical model in modern PBL dynamics have been applied to derive order-zero and order-one analytic solutions over large-scale topography,the solutions are used to obtain the divergence and vertical velocity, improving the previous results.     

厄尔尼诺事件与地震

本文采用概率统计、回归分析及灰色关联度相关分析方法,全面地分析、研究了中国及世界范围内的多震区域的地震资料和乓尔尼诺事件的资料,发现厄尔尼诺事件与地震活动从大范围来看似无明显的相关关系,但与局部地区的地震活动明显相关。该事件的发生与东太平洋隆起地区、菲律宾群岛等地区的地震高频年相对应,与我国台湾地区、青藏高原等多震地区发生的地震也有较好的对应关系。     

Moment tensor inversion of some aftershocks of the April 18, 1985 Luquan earthquake of Yunnan Province, China

Based on the three component accelerograms, recorded at near-field distance by a temporary seismic network consisting of digital cassette tape recording accelerographs, the focal mechanisms of three aftershocks of the April 18, 1985, Luquan, Yunnan Province, China, earthquake ofM _S=6.1, are calculated using seismic moment tensor inversion technique. The phases of direct P, S and converted SP waves in the displacement seismograms, produced by twice integrations of the observed accelerograms, are identified via forward calculation using Green’s functions for homogeneous semi-infinite elastic medium, and used in the inversion. The results of inversion show that a better fit of synthetic to the observed seismograms of direct as well as converted phases can be achieved if appropriate weighting functions are used in solving the over definite linear equations. While these aftershocks are of different magnitudes (M _L=4.8, 3.2 and 3.5, respectively) and hypocentral locations, their focal mechanisms are very similar and consistent with that of the main shock. This feature demonstrates the intrinsic correlation between the occurrence of aftershocks and the seismogenic fault of main shock. Our experimentations show that using the near field accelerogram obtained from the digital seismic network with appropriate azimuthal coverage on the focal sphere, with the aid of even simple medium model, not only the shear dislocation source, but also the isotropic part and CLVD (compensated linear vector dipole) can be retrieved by the technique of moment tensor inversion. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 412–419, 1991. This work is supported by the Chinese Joint Seismological Sciences Foundation and the Western Yunnan Earthquake Prediction Test Site (WYEPTS), State Seismological Bureau.     

微机窗口系统的一种实现方法

本文开发的弹出式窗口系统和下拉式菜单系统,具有显示速度快、通用性好、移植性强的特点。全部程序在VGA/EGA的PC机上调试通过,取得了较为满意的效果。笔者愿提供大家广为利用。     

正压模式中慢波的离散谱及其特征函数

本文对正压模式中慢波的离散谱及其特征函数作了数值计算。结果发现，在低速线性缓变切变基流的情形下，正压原始方程中慢波可有离散谱存在。本文还给出了在该基流下算得的谱点和特征函数，并与准地转模式的计算结果进行了比较。     

陕西省矿泉水资源特征及开发对策

陕西省矿泉水资源丰富，开发条件优越，但发展速度较慢，存在着不少问题。针对全省矿泉水资源特点及开发中存在的问题，提出了矿泉水开发的具体对策。     

2011年日本MW9.0地震对沂沭断裂带及其两侧地区地壳运动的同震影响研究

2011年日本M_W9.0地震（简称日本地震）后沂沭断裂带及其两侧地区地震活动显著增强,研究日本地震对该地区地壳运动及地震潜势的影响十分必要.为此,本文通过112个连续GPS观测站获取了研究区高空间分辨率的日本地震同震形变场并得到如下认识：（1）8个定点地球物理观测的同震响应验证了本文同震形变场的可靠性;日本地震的东向拉张使研究区整体上处于张性同震应变状态,但存在局部挤压区域,其中莱州湾至海州湾的挤压条带穿过沂沭断裂带并对断裂带南北两段产生了不同的同震作用,对南段具有拉张作用,对北段产生挤压作用;（2）同震形变场在鲁东隆起和鲁西断块产生了显著的剪应变,地震b值显示上述区域的构造应力在日本地震后增强,因此同震形变场可能改变了这些区域的应力特征;（3）地震矩张量叠加分析显示,同震形变场短期内对鲁西断块、鲁东隆起区和沂沭断裂带南段累积了地震矩,可能有助于上述区域在日本地震以后的地震活动增强;日本地震对沂沭断裂带北段的地震矩具有释放作用,或许是该区域地震活动减弱的原因.     

TYPHOON ACTIVITY IN NORTHWEST PACIFIC IN RELATION WITH EL NINO AND LA NINA EVENTS

Statistic and typical-year composition methods are used to study the northwest Pacific typhoon activities in relation with the EI Niño and La Niña events. The result indicates that the typhoon tends to be inactive in the EI Niño years and active in the La Niña years and it is also dependent on the onset and ending time and intensity of the events and areas of genesis of typhoons. With statistic features of the frequency of typhoon activity in the EI Niño and La Niña years and the time-lag correlation between the frequency and sea surface temperature(SST), useful information is provided for the prediction of typhoon occurrence. In addition, the singular values disassemble(SVD)method is applied to study the correlation between the geopotential field and SST field. The result shows that the air-sea coupling in the EI Niño years is unfavorable for the typhoon to develop. Which take place with a smaller number. Opposite situations are found with the La Niña years.     

超新星遗迹X射线研究

在此介绍我们基于ＡＳＣＡ 和ＲＯＳＡＴ 等Ｘ 射线天文卫星,对３Ｃ３９７ 、Ｇ３２７ ．１１ ．１ 、Ｇ２１ ．５０ ．９ 和ＲＸＪ１７１３ ．７３９４６ 等超新星遗迹的物理特性进行的分析,简要地讨论了３Ｃ３９７ 的非平衡电离双热分量和双极泡结构以及Ｇ３２７ ．１１ ．１ 和Ｇ２１ ．５０ ．９ 中隐匿脉冲星的性质,并提出ＲＸＪ１７１３ ．７３９４６ 和ＡＤ３９３ 客星之间可能的关系。