华北平原周边北西向强震地表地震断层及全新世断裂活动特征

讨论了华北平原周边１９７５年海城地震，１９３７年荷泽地震及１８３０年磁县地震３次强震的地表地震破裂特征以及这３个地区北西向断裂的全新世活动。研究结果表明，尽管这３次强震地表破裂显示较弱，断续分布，仍反映了存在北西向地表破裂带，活动方式呈左旋走滑兼正倾滑。     

岩石应力状态改变引起岩石热状态改变的研究

岩石的应力状态发生改变是否能引起岩石的热状态发生改变，是一个值得研究的重要问题，我们在实验室对岩石试件进行实验，实验得出岩石的温度随岩石受到的压力增加而显著增加，在试件破裂前出现明显的破裂温度前兆；实验还发现岩石内部温度随压力变化的不均匀性，不同测温点的温度变化不同，其变化量可相差几度。     

On the causes of unordinary periodicity of earthquakes

The diurnal periodicity of seismic events from three earthquake catalogs of Fennoscandia and Turkey is studied. The shape of diurnal distribution of seismic events in all the catalogs under investigation is similar to the unordinary diurnal periodicity of earthquakes described in previous papers. The principal feature of the diurnal periodicity of seismic events revealed in this paper is a wide maximum of the events in the day time. The very reliable conclusion is made that it is caused by presence of a great amount of quarry blasts in the catalogs.     

Features of the diurnal periodicity of earthquakes in Japan

The features of the diurnal periodicity of earthquakes with different energies in Japan are studied. The spatiotemporal parameters of different earthquake sets are investigated in detail using various techniques including analyses of amplitudes, dispersion, spectra and correlation. The phases of seismic flows are studied using the modified Rayleigh-Schuster method. Lomb-Scargle periodograms are used to study the frequency of variations in seismicity. The parameters of the sets of earthquakes having different energies obtained in this study indicate changes in phase of the diurnal periodicity of earthquakes to the opposite near the magnitude of completeness. The very clear midday effect is noted.     

Evaluation of Negative Economic-Environmental Externalities of Overextraction of Groundwater

In recent decades, increased extraction of groundwater for human and agriculture consumption has led to a substantial drop in groundwater level in large areas of across the world. Declining groundwater levels is a serious problem in itself and has multiple economic, social, cultural, political, security-related, and environmental externalities. The negative economic-environmental externalities of overextraction of groundwater in the Orzouiyeh plain in the Kerman Province, Iran, were evaluated using methods such as replacement cost, production function, market prices, shadow price, and the value of the input marginal product. After evaluating externalities, the Positive Mathematical Programming method was used to evaluate different water policies to reduce the consumption of groundwater. The total economic losses due to the externalities were calculated to equal 2.8 U.S. million dollars. The damages caused by environmental externalities were calculated to equal 436.1 U.S. million dollars. The results related to the positive planning model show that the best policy among different options, such as deficit irrigation policy or combined policies, involves implementation of pressurized irrigation systems.     

Review of behaviour of oil in freezing environments

The current knowledge of the physical fate and behaviour of crude oil and petroleum products spilled in Arctic situations is reviewed. The fate and final deposition of oil in marine conditions is presented as based on the extant literature.

Spreading models were evaluated for oil on ice, under ice, in snow, in brash ice, and between blocks of ice. Models of oil transport under sheet and broken ice were considered, both for sea and river conditions. The ability of ice sheets to trap oil is discussed in relation to oil storage capacity. The effects of oil on a growing ice sheet were examined, both in terms of ice formation and the thermal effects of oil inclusions in ice. The migration of oil through ice was reviewed, focussing primarily on the movement through brine channels. The effects of oil on the surface of ice were considered, with emphasis on the effects of surface pools on ice melt. Similar consideration was given to the effects of oil on snow on the surface of ice.

The few quantitative studies of oil in open and dynamic ice conditions are reviewed. Observations of intentional small-scale spills in leads and ice fields are reviewed and compared with observations from real spills. The conditions under which “oil pumping” from leads occurs were quantified. The most common ultimate fate of oil in an ice field is to be released onto the water surface.     

加卸载响应比理论在以磁报震中的应用探索

加卸载响应比理论具有雄厚的物理基础，把它引用到以磁报震中，即有利于以磁报震工作的发展，也是对加卸载响应比理论应用的延拓。我们取太阳日照为加载，地磁垂直分量Ｚ为响应，研究了利用北京台１９７０－１９８６年资料所计算出的响应比与１９７６年唐山大地震的关系。结果发现１９７６年地震前约半年时间内的响应比明显高出其他各年。通过地震前后共１７年的资料分析，确认这正是地震前兆。     

空间大地测量技术在火山形变监测中的应用

岩浆活动的不同阶段引起地表变化不同。地表形变受压力源大小、形状、深度及岩浆运移速率等影响;另外火山类型不同,地形不同,形变特征也不同。地表形变幅度范围很大,为1×10-7—1米量级。火山区形变监测可以了解火山活动状态,有助于进行喷发危险性的预测预报。形变监测从20世纪60年代的传统技术逐渐过渡到20世纪90年代发展起来的GNSS和InSAR等大地测量新技术,火山区形变时空监测能力得到提高,同时缩短了预测时间。我国火山形变监测开始较晚,现已在长白山天池、腾冲以及海南等主要火山区开展监测。传统的连续测量以地倾斜观测为主;新技术主要以流动GNSS监测为主,连续观测站少,InSAR技术研究时间密度不够;目前形变监测还不能实现很好的时空覆盖。     

砌体结构抗震抗剪强度分析

进行了墙体抗剪强度理论和公式的研究。将主拉强度理论与剪摩强理论相结合,形成了一种新和强度理论,即拉摩强度理论。根据该理论,导出了墙体抗剪强度公式。给出了公式系数的确定方法,并确定了砖墙体的公式系数。将本文建议的砖墙体抗剪强度公式与抗震和砌体规范采用的抗剪强度公式进行了比较,比较结果表明：抗震规范公式值较小;砌体规范公式值较在,本文公式值介于两者中间。     

Natural and Anthropogenic Variations of the Concentrations of Iron,Copper, and Zinc in Water Streams of the Republic of Bashkortostan

The natural and anthropogenic sources of iron, copper, and zinc in water streams in the Republic of Bashkortostan are considered. Statistical analysis of long-term hydrochemical monitoring data was used to establish the spatial year-to-year and annual regularities in metal concentrations in water streams. The acceptability of river water quality for different types of water use was estimated. The exceedance probabilities of metal MAC values in streams were evaluated.     

Rigidity of rocks of an earthquake source region in the period of aftershock activity

Aftershock series of known strong earthquakes differ in duration and energetics. The study of geological properties of an earthquake source region is of interest in two aspects: (1) acquisition of constraints on the source development process and (2) detection of precursors of strong aftershocks. The latter are dangerous because they complete the process of damage of industrial and civil structures. Cases of aftershocks comparable in energy to the main event are known in seismological practice (the Tashkent, 1966, and Gazli, 1976, earthquakes). The seismic situation in Koryakia (2006) is very significant in this respect. The paper assesses the possibilities of rigidity monitoring for the study of the aftershock stage of the source development process with the use of earthquakes in California (the United States) as an example.     

Modeling the formation of undulations of the coastline: The role of tides

An idealized model is developed and analyzed to investigate the relevance of tidal motion for the emergence of undulations of a sandy coastline. The model describes feedbacks between tidal and steady flow on the inner shelf, sand transport in the nearshore zone and an irregular coastline. It is demonstrated that an initially straight coastline can become unstable with respect to perturbations with a rhythmic structure in the alongshore direction. The mechanism causing the growth of these perturbations is explained in terms of vorticity concepts. The relative importance of tide-related and wave-driven sediment fluxes in generating undulations of the coastline is investigated for the Dutch coast. Using parameter values that are appropriate for the Dutch coast it is found that tides can render a straight coastline unstable. The model predicts a fastest growing mode (FGM) with a wavelength that is in the order of the observed length of barrier islands. The mode grows on a time scale of 50 yr and it migrates 200 m per year. The wavelength of the FGM decreases with increasing amplitude of the tidal currents. This result is consistent with data of tides, waves and the lengths of barrier islands that are located along the Dutch and German Wadden coast.     

Estimation of rainfall elasticity of streamflow in Australia

Abstract

Estimates of rainfall elasticity of streamflow in 219 catchments across Australia are presented. The rainfall elasticity of streamflow is defined here as the proportional change in mean annual streamflow divided by the proportional change in mean annual rainfall. The elasticity is therefore a simple estimate of the sensitivity of long-term streamflow to changes in long-term rainfall, and is particularly useful as an initial estimate of climate change impact in land and water resources projects. The rainfall elasticity of streamflow is estimated here using a hydrological modelling approach and a nonparametric estimator. The results indicate that the rainfall elasticity of streamflow (? _P ) in Australia is about 2.0–3.5 (observed in about 70% of the catchments), that is, a 1% change in mean annual rainfall results in a 2.0–3.5% change in mean annual streamflow. The rainfall elasticity of streamflow is strongly correlated to runoff coefficient and mean annual rainfall and streamflow, where streamflow is more sensitive to rainfall in drier catchments, and those with low runoff coefficients. There is a clear relation-ship between the ? _P values estimated using the hydrological modelling approach and those estimated using the nonparametric estimator for the 219 catchments, although the values estimated by the hydrological modelling approach are, on average, slightly higher. The modelling approach is useful where a detailed study is required and where there are sufficient data to reliably develop and calibrate a hydrological model. The nonparametric estimator is useful where consistent estimates of the sensitivity of long-term streamflow to climate are required, because it is simple to use and estimates the elasticity directly from the historical data. The nonparametric method, being model independent, can also be easily applied in comparative studies to data sets from many catchments across large regions.     

Effects of and methods for determination of induced magnetic anisotropy of igneous and metamorphosed rocks

The phenomena of the magnetic memory of rocks associated with paleointensity, paleotemperature, and paleostress are reviewed and discussed here. The methods for the determination of the paleointensity and the paleoconditions are described and discussed in terms of their sensitivity and applicability. The determination of paleoconditions (stress and temperature) is essential for understanding rock mineral formation and rock history. Such knowledge is applicable also in ore deposit geology and geophysics. The phenomena of the magnetic memory manifest themselves through the constriction and asymmetry in the hysteresis loops, as well as through a nonlinear pattern in the anhysteretic magnetization curve, both being due to the induced magnetic anisotropy. The pros and cons of some applied methods are reviewed. The superposition of several paleotemperatures (re-heatings of the rock) and/or paleostresses is studied also. Under certain conditions, a rock can remember information on several paleotemperatures (paleo-heating events), as well as the respective intensities of the geomagnetic field of the past.     

Discreteness of spatial-temporal manifestations of solar activity and solar-terrestrial phenomena

The discreteness of the time series of the solar-related geophysical phenomena is justified. The balance of the formation and decomposition (neglecting diffusion) of fractal elements during the evolution of the equilibrium systems as applied to the heliophysical and geomagnetic phenomena is the original position in this case. The discreteness properties of the spatial-temporal characteristics of solar activity are simply justified based on a fractal analysis. The performed calculations in the solar wind medium in the near-Earth space make it possible to classify the fluxes depending on their fractal dimension. The possible mechanism by which high-speed solar wind streams are generated is also briefly discussed in the scope of the fractal paradigm.     

区域滑坡时间分布的自相似性研究

滑坡时间分布是滑坡预测和预警报研究的关键内容,对一定区域滑坡分布时间规律的研究可为区域滑坡预测和预警报提供参考和指导。本文以长江三峡库区滑坡为研究对象,对滑坡的年际分布和月份分布的相似性分别进行了研究。结果表明,两种时间的分布规律具有较好的相似性,且滑坡规模越接近,相似性程度越高。对滑坡时间分布的相似性研究,为应用分形理论研究该区域滑坡时间分布规律提供了理论基础。     

Characteristics of the Ecosystems of Water Bodies Separating from Kandalaksha Bay of the White Sea

The coastal water bodies that separate from White Sea water area due to Kandalaksha coast rise are examined. The hydrological and hydrochemical characteristics of these water bodies are found to notably differ from these in the bays and straits connected with them. Extreme values of water temperature and salinity were recorded. High concentrations of oxygen (>20 mg/l) were recorded in the near-surface water layers and high concentrations of hydrogen sulfide (>90 mg/l) in bottom waters. The species composition of phyto- and zooplankton was found to be poor. The characteristics of enzymatic destruction in subsurface waters of lakes are an order of magnitude greater than those in White Sea open areas.     

淮河干流浮游动物群落结构特征

2011年3、6、9和12月对淮河干流11个采样点的浮游动物群落结构进行调查研究,共检出浮游动物79属206种,其中原生动物27属69种,占浮游动物总物种数的33.5%;轮虫35属104种,占50.5%;枝角类12属27种,占13.1%;桡足类5属6种,占2.9%.总体上看,从上游至下游,浮游动物物种数呈现逐渐减少的趋势.浮游动物的丰度和生物量分别为3527447 ind./L和2452 mg/L,轮虫和原生动物丰度是淮河干流浮游动物丰度的主体,轮虫生物量是淮河干流浮游动物生物量的主体,浮游动物及各类群丰度和生物量均表现为从上游到中游逐渐增高的趋势,而从中游到下游呈现逐渐降低的趋势.上游浮游动物多样性指数和均匀度指数高于中、下游.结果表明:淮河干流上游水质为轻污染,中、下游水质为中污染或重污染.浮游动物群落结构和环境因子的冗余分析表明,水温、溶解氧和流速是与淮河干流浮游动物群落结构相关性较强的环境因子.     

Spacio-temporal history of the deep Colombia earthquake of 1970

The deep Colombia earthquake of July 31, 1970, showed a very high multiple-shock activity. The hypocentres of the seven events forming the multiple shock were determined by a relative location method. They cluster on a plane which coincides fairly well with the westerly-dipping nodal plane and show a southwards and upwards migration with time. The hypocentre distribution suggests that the earthquake occurred in the form of shear faulting. The primary P waveforms are computed from the long-period P-wave signals by eliminating the responses of the instrument, crust and mantle. The fault process is inferred from the spacio-temporal relation of the seven events and from the primary P waveforms: the rupture initiated in the lower part of the source region and spread out southwards and upwards. The whole process was almost finished when the intense multiple-shock activity terminated (about 50 s). The mechanism change of this earthquake can be described mainly by the change of the orientation of the fault plane rather than by slip vector change. The strike of the fault plane rotated clockwise about 10° during the events which occurred in the lower part of the source region. The further rotation of about 10° occurred at the subsequent stage. The rupture spread out with a jerk over a curved surface. The difference between the rupture processes in shallow and deep large earthquakes is discussed.     

Study of charge structure and radiation characteristic of intracloud discharge in thunderstorms of Qinghai-Tibet Plateau

The comprehensive observations on lightning discharges were conducted in Naqu area of Qinghai-Tibet Plateau in summer of 2002. The electric structures of thunderstorms and the characteristics of lightning discharges at initial stage were analyzed by using the observation data. The results show that most of intracloud (IC) lightning flashes were polarities inverted in thunderstorms with tripole electric charge structure and occurred between negative charge region located in the middle of the thunderstorm and positive charge region located at the bottom of the thunderstorm. The radiation characteristics of discharge processes in cloud with longer lasting time involved in Cloud-to-Ground (CG) lightning flashes were similar to that of IC discharges.A lot of radiation pulses were produced in these discharge processes. Because the IC discharges took place at the bottom of thundercloud and were near the ground, they may produce more serious damage to equipment on the ground therefore should not be neglected in lightning protection.