利用功率谱直接求埋深的影响因素

功率谱方法在磁数据处理方面的应用比较广泛。采用近似公式直接求出地质体的上下底埋深。在此近似方法中,会出现一些影响结果的因素。主要对地质体的水平尺寸和厚度的影响做了一些研究,并得出相应的结论。     

Experience of using a dynamic stochastic approach for solving the problem of very short-range forecasting of state parameters of the atmospheric boundary layer

Discussed are the results of applying a dynamic stochastic method based on the use of the two-dimensional model and the Kalman filtering algorithm for solving the problem of the very short-range (from 0.5 to 6 hours) fore cast of air temperature and orthogonal components of the wind speed in the atmospheric boundary layer realized using the data of radio metric, sodar, and in creased-frequency radiosonde measurements. It is demonstrated that the pro posed technique and the appropriate algorithm give a rather high ac cu racy of very short-range fore casting of temperature and wind within the lead time range under consideration.     

A new approach to the automatic computation of partial volumes of river runoff with various degrees of pollution (a case study for the Selenga River)

Proposed are the methods and software package that enable estimating automatically the degree of the pollution of annual and long-term river runoff at the joint processing of large volumes of standard (routine) hydrological and hydrochemical information. As a result of computations, the individual quality certificate of river runoff was created for the part of the river under study. Computation methods include regulations concerning the parameters that connect the water runoff volume with water quality; the parameters that may connect the computation of the pollution degree using RD 52.24.643-2002 adapted for the partial volumes of the annual runoff according to these methods, with the subsequent classification of the pollution degree. The computation technique was worked out and used for the first time. The informativeness of estimates is demonstrated for one of the discharge section lines of the Selenga River.     

Volcanic highlands in the South Atlantic rift zone

The morphostructure of the segment between the Cardno and St. Helen transform fracture zones is studied in the rift zone of the South Atlantic slow-spreading mid-oceanic ridge (SAMOR). It was found that it is atypical of similar ridges because of the absence of an evolved rift valley. The rift zone in the transverse section is a cupola with flat slopes, whose surface is divided by volcanic massifs, plateau-like valleys, and unclear ridges and valleys. The entire morphostructure (a cupola-like regional pedestal and the listed relief forms of the second order) indicates its volcanic origin, and the rift zone in this segment is a volcanic high-land. This conclusion is supported by seismic and magnetic data. Because other (not all) SAMOR segments contain the rift valley, the results of this study indicate alternation of the tectonic and magmatic morphostructures along the entire rift zone and identification of its scales is the most important task of the morphostructural study of the SAMOR rift zone. Determination of geodynamic regimes on the basis of the results of morphostructural studies of the rift zone will arise from the solution of this task.     

The effect of the geomagnetic activity to the hourly variations of ionospheric foF2 values at low latitudes

In this study, the relationship between the hourly changes of the ionospheric critic frequency values of F2 layers in low latitudes and geomagnetic activity is examined by using statistical methods. The ionospheric critical frequency data has been taken from the Manila (121.1° E, 14.7° N) ionosonde station. In order to investigate the effect of sun activity on ionospheric critical frequency, the data of 1981 when the sun was active and of 1985 when the sun was less active has been used. According to the Granger causality test results, on 5 % significance level, a causality relationship from disturbance storm time (Dst) index values to ionospheric critical frequency values direction has been observed. However, a causality relationship from ionospheric critical frequency values to Dst values has not been observed. From the results of cause-and-effect analysis, it is evaluated that the effect of a shockwave occurring in geomagnetic activity on ionospheric critical frequency continues along 72 h, that is, geomagnetic activity has a long-term effect on ionospheric critical frequency. The response of ionospheric critical frequency to geomagnetic activity substantially depends on seasons. This response is more observed especially in equinox period when the sun is active and in winter months. The increase in geomagnetic activity causes ionospheric critical frequency to decrease in night hours and increase in day hours. The same relationship has not been observed exactly, though observed very little in winter months, for 1985 when the sun was less active.     

Relation between the “Double-Hump” Behavior in the Radio Band and the Broad-Line Luminosity for Blazars

The physics behind the spectral energy distribution (SED) of blazars remains open. We assembled 36 blazars to tackle the factors that control their SED. Now, many blazar spec- tra have the "double hump" feature in the radio and far-IR frequencies. For these a parameter, , is created to characterize the behavior of the SED. We found a significant correlation be- tween the broad-line luminosity (LBLR) and . Because LBLR is an indicator of the accreting power of the source in blazars, we derived a linear correlation, ∝ M˙1/3.18, which suggests that the SED of blazars may depend on the accretion rate, like that of BL Lac objects. We also found a significant correlation between ■ and for a sample of 11 blazars (out of one of 36) with available black hole masses. This implies the Eddington accretion ratio may influence the shape of the SED of blazars.     

鲜水河断裂带现今断层运动短周期事件的发现与初步研究

根据鲜水河断裂带上连续动态地壳形变台阵数据，首次揭示了中国大陆板内断层现今运动的短周期现象，包括蠕变阶、蠕变坡和脉动等，其持续时间为数分钟至数十小时。发现其空间分布与断层分段（闭锁或活动段）有关；其时间分布与强地震孕育过程有关。蠕变过程符合Ｌｏｍｎｉｚ提出的对数蠕变函数，可能是断层面不均匀结构中的局部流变行为。断层短周期事件对揭示断层不均匀结构和微破裂过程动力学有重要意义，并可能发展为一种新的地震前兆     

海底扩张的潮汐模式

2000年6月底，东京以南的伊豆岛开始发生火山与地震活动。此后，在伊豆岛观测到异常的地壳变形，8月底，火山与地震活动达到高潮。对潮汐与火山和地震活动的关系进行了分析，认为：地壳变形是由伊豆岛的岩脉侵入引起的，并且与强潮汐天文条件相对应。根据观测和计算数据提出了海底扩张的潮汐模式。     

Connections Between Different Types of El Nio and Southern/Northern Oscillation

It has long been acknowledged that there are two types of El Nio events, i.e., the eastern Pacific El Nio (EE) and the central Pacific El Nio (CE), according to the initial position of the anomalous warm water and its propagation direction. In this paper, the oceanic and atmospheric evolutions and the possible mechanisms of the two types of El Nio events were examined. It is found that all the El Nio events, CE or EE, could be attributed to the joint impacts of the eastward advection of warm water from...     

Climatic characteristics of convective and stratiform precipitation over the Tropical and Subtropical areas as derived from TRMM PR

Climatic characteristics of convective and stratiform precipitation over the Tropical and Subtropical areas are investigated based on the measurements of Tropical Rainfall Measuring Mission’s(TRMM) Precipitation Radar(PR) from 1998 to 2007.Results indicate that convective precipitation are distributed mainly over the Intertropical Convergence Zone(ITCZ),the South Pacific Convergence Zone(SPCZ),the Asian Monsoon Region,regions between the South America and the Mid-America,and the Tropical Africa where the frequencies lie between 1% and 2%.But in four seasons,total area fractions of convective precipitation frequencies less than 1% all exceed 85%.The frequencies of stratiform precipitation are much higher than those of convective precipitation,and total area fractions of stratiform precipitation frequencies >1% are over 55% during four seasons.However,frequencies of the two rain types show not only remarkable regionality,but also distinct seasonal variations.Conditional rain rates of convective precipitation range from 6 to 14 mm/h whereas those of stratiform precipitation are smaller than 4 mm/h.Meanwhile,rain tops of convective precipitation are higher than those of stratiform precipitation.The mean profiles of the two rain types show significant latitudinal dependency.And the seasonal variations of precipitation profiles are displayed mainly in the variations of rain tops.The frequencies and conditional rain rates of both rain types over ocean are higher than those over land,but rain tops are just the opposite.Moreover,the seasonal variations of both rain types over ocean are weaker than those over land because of the different stable states of underlying surfaces.