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水氡动态图强震危险区预测的新方法 总被引：4，自引：0，他引：4
水氡动态图强震危险区预测法是一种地下流体的地震分析预报新方法。 对该方法做了系统的介绍,其内容有: 水氡基值变化率动态图像的生成方法,水氡变化率高值异常区图形演化与地震震中位置的关系,强震危险区预测的标志与方法。检验性预测结果表明,该方法具有预测效能,可在实际地震预报中使用。 相似文献
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全球定位系统(GPS)观测和信息处理技术的发展, 为获取高精度地壳水平运动和相关的应用研究提供了良好的基础． 应用中国地壳运动观测网络中心提供的1999—2007年GPS水平形变速率观测结果, 研究了地壳水平形变面应变率梯度与强震发生的关系, 探索了地震中长期预测对强震危险区的判识方法． 结果表明, 中国大陆2001—2011年发生的大部分MS6.8以上强震, 地震地点均位于面应变梯度高-低值过渡区与块体边界带相交汇的部位; GPS面应变率梯度可以作为中长期强震危险区判识的一种方法, 与最大剪应变率分布相比, 缩小了强震孕育地点的判识范围． 文章最后给出了中国大陆地区未来10年或稍长时间的强震危险区. 相似文献
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地震活动性震级结构和前兆特征分析及其在地震预测中的应用 总被引：1，自引：0，他引：1
研究中小地震活动特征 ,探讨其物理意义及其与强震的关系是一个引起广泛关注、具有重要理论意义和应用价值的研究方向。本文以判定中长期大陆强震的发生地点为目标 ,强调从中小地震活动性图像提取前兆信息的方法应具有可重复性 ,前兆特征应较为稳定且有一定的物理意义 ,并要求选取的前兆应以尽量大的比率对应强震 ;依据该前兆划定的强震危险区的范围应尽可能地小。根据上述研究目标和要求 ,本文确立了中小地震活动性图像定量、全时空扫描和分震级处理的原则。强调使用定量方法处理中小地震活动性图像 ,目的是使这一工作具有可重复性 ;全时空… 相似文献
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根据新疆天山活断层新活动特征、卫星影象显示的线性构造与地震活动显示的网络构造,确定出天山可能发生强震的警戒断层有:独山子——安集海活断层、清水河子与精河——阿什里活断层、卡克博河与特克斯河活断层、兴地活断层和北轮台活断层。综合分析判定出5个未来十年可能发生强震的危险区:沙湾西南强震危险区、乌鲁木齐西南新生强震危险区、新源西新生强震危险区、库尔勒东强震危险区和轮台北新生强震危险区。研究结果表明,天山地区全新世活断层新活动颇为强烈,某些活断层具有控震作用。预测今后十年新疆天山地区有发生多个6.5级以上地震的可能。 相似文献
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一年至几年时间尺度的强震危险区预测，是当前地震预测工作急需解决的重要问题之一。在活断层研究的基础上，划分出近期活动的预警活断层，再在判定为预警活断层上圈定中期强震危险区。实践证明这是一个有效的办法。 相似文献
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D. M. Pechersky A. A. Lyubushin Z. V. Sharonova 《Izvestiya Physics of the Solid Earth》2010,46(7):613-623
The data on geomagnetic reversals are compared with the changes in the organic world and with the lower-mantle plumes. The
times of the formation of plumes and the times of their appearance on the Earth’s surface relate to the intervals characterized
by the different frequencies of geomagnetic reversals, i.e., there is no interrelation between the formation of plumes and
the frequency of the changes in the geomagnetic field polarity. At the same time, a certain synchronism is observed between
the frequency of the geomagnetic reversals and the boundaries of the biostratigraphic ages, i.e., the changes in the organic
world in the long-period range. A hypothesis is proposed, which explains the change in the sign of the geomagnetic field by
the combined effect of the irregular rotation of the internal core relative to the mantle and the changes in the slope angle
of the axis of the Earth’s rotation, which, in turn, results in synchronous events on the Earth’s surface: the rates of changes
in the organic world. 相似文献
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The nutations of the planets Mars andEarth are investigated and compared. Alarge number of interior structureparameters are involved in the nutationcomputations. The comparison between the observations and the computationsprovides several constraints on these parmeters andtherefore allows a better understanding of the physics of the interior of theplanet. For the Earth, the high precision of the observations of the nutationshas led to a very good determination of interior properties of the planet. ForMars, observations of nutations are not yet available, and we review how theamplitude of the Martian nutations depends on the hypotheses consideredfor its interior. Although Mars is very similar to the Earth, its interior is not well known;for example, we don't knowif its core is liquid or solid. Only if the core is liquid,the Free Core Nutation (FCN) normal mode exists and can alter the nutationswhich are close to the resonance. From the observed geoids, it is known thatboth planets are not in hydrostatic equilibrium. The departure is larger forMars than for the Earth, and consequently, the implication of considering a convective mantle instead of a mantle in hydrostatic equilibrium described byClairaut's equation for the initial equilibrium state of the planet is largeron the Martian nutations than on the Earth nutations. The consequences of theuncertainty in the core dimensions are also examined and shown to be of a veryhigh influence for Mars if the core is liquid, due to the potential changes inthe FCN resonance. The influence of the presence of an inner core, which isknown to exist for the Earth, could be more important for Mars than for theEarth if the inner core is large. Due to the presence of Tharsis on Mars, thetriaxiality of this planet has, additionally, larger effects than on Earth. 相似文献
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综合APIA、HONOLULU、PAMATAI 3个地磁台三分量的11年周期变化的形态后,可定性地提出该变化源于内场。如内源为核幔边界的电涡流,则其中心点应位于3台之间。 相似文献
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The depth to the top of magnetic dykes can be estimated from total field aeromagnetic data using the relation between the depth to magnetic sources and the autocorrelation function of magnetic data. By using synthetic anomalies we show that in the ideal case, depth can be determined to an accuracy of 10% or better, when the anomaly sources are two-dimensional dykes. However, the estimated depths depend on the width of the dykes. The estimated depth is about 0.6 times the actual depth to the top of thin dykes, and around the true depth for thick dykes having width-to-depth ratio around 3. The depth is considerably overestimated for very thick dykes (e.g., contacts, which is a special case of the thick dyke). Thus, the autocorrelation method requires that the width-to-depth ratio of the dyke is estimated independently to correctly estimate the depths. Alternatively, it must be assumed that the width-to-depth ratio for the two-dimensional source body is between 1.5 and 4. 相似文献
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As is known, the secular deceleration of the Earth's diurnal rotation is explained mainly by the tidal friction in the ocean. Below we consider this mechanism in some detail, taking into account also elastic deformations of the mantle under the action of ocean loading and the interaction between the tide-generating body, ocean tidal wave, liquid outer core, and solid inner core. It is shown that elastic displacements of the core-mantle boundary under the action of ocean loading are of about the same amplitude and phase as the elastic loading displacements of the Earth's outer surface. As a result, side by side with the mechanism of secular deceleration of diurnal rotation of the mantle, there are also (1) the opposite mechanism of secular acceleration of diurnal rotation of the outer liquid core and of the solid inner core and (2) the mechanism of excitation of differential rotation in the liquid core. Taking these effects into account, we compare theoretical and modern observed data on the eastward drift of the solid inner core. It is shown that the best agreement may be obtained if the turbulent viscosity of the liquid core is about 2 × 10
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Poise 相似文献
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On data of bottom sampling, carried out by means of grab, trawl and underwater photography in August–September of 1993 in the area of the Pechora Sea, quantitative regularities of macrobenthos distribution are described for the ecological monitoring purposes. Maps of -biodiversity and biomass indices, bottom communities and trophic zones, singled out by dominant method, are presented. Assessment of structure changes of the investigated area bottom communities during the last 60–70 years is fulfilled. It is shown that the described communities on the whole are of natural undisturbed character and that the revealed changes are within the natural fluctuations in the abundance of benthic populations or may be interpreted in terms of methodical differences in the data analysis and generalization by different authors. 相似文献
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地震激励下处于深水中的桥墩和周围水体的相互作用将对桥梁结构的动力响应产生较大影响。首先对地震作用下水-桥墩的相互作用理论做了概括,给出了动水压力对桥墩的作用效应及各自的适用范围;对主要的三种考虑流固耦合效应的分析方法做了对比,探讨了地震作用下影响水-结构相互作用的主要因素,并对今后的研究提出了建议。 相似文献
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Summary The maintenance of the axisymmetric component of the flow in the atmosphere is investigated by means of a steady-state, quasi-geostrophic formulation of the meteorological equations. It is shown that the meridional variations in the time-averaged axisymmetric variables can be expressed as the sum of three contributions, one being due to the eddy heat transport, another to the eddy momentum transport, and a third to the convective-radiative equilibrium temperature which enters the problem through the specification of a Newtonian form of diabatic heating. The contributions by the large scale eddies are evaluated through the use of observed values for the eddy heat and momentum transports.The contributions from each of the three forcing mechanisms to the temperature and zonal wind fields are invstigated individually and found to be of about equal importance. The sum of the three contributions are also presented for the temperature, the zonal wind, the stream function associated with the mean meridional circulation and the corresponding vertical motion. Although the results fail to reproduce the main observed features of the lower stratosphere, they are found to be in good agreement with observations in the middle latitude troposphere. At any pressure level, for example, the computed mean zonal wind has a jet-like profile and the axis of the jet is found to slope to the south with height, as observed in the atmosphere.Based in part on a thesis submitted by the first author as partial fulfillment of the requirements for the Ph.D. degree at the University of Michigan. — Publication No. 194 from the Department of Meteorology and Oceanography, The University of Michigan. 相似文献
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在数据完整率达到95%的基础上,为进一步确保中国大陆构造环境监测网络GNSS基准站观测数据质量,选取2010—2020年全国基准站观测数据,采用TEQC软件进行质量检验,分类整理其中多路径效应计算结果呈典型特征的台站,结合观测环境状态,对多路径效应存在的区域性特征进行分析,发现除接收机天线周围发生遮挡外,硬件更换、台站周围地势差等因素,均对多路径效应产生不同程度的影响,可为建站选址和观测环境监测工作提供参考。 相似文献