马家沟矿断层赋存规律及其对生产的指导作用     

张计恒  谢玉祥 《中国煤田地质》2004,16(Z1):4-5

笔 者 结合 工 作 实 践 ,概 述 了 马 家 沟 井 田 范 围 内 断 层 发 育 的 特 点 及 其 基 本 规 律 ;重 点 分 析 了F2断 层 的 赋 存 特征 ,简 要说 明 了根 据断 层赋 存 规律 对生 产 的指 导作 用 。  相似文献   

钱家营矿首采区断层在剖面上的延伸规律     

姚仲宝  刘金国 《中国煤田地质》2004,16(Z1):10-11

通 过对 开滦钱 家营 矿首采 区地 质资料 的综 合分析 ,得 出了 该 矿首 采区 断 层在 剖面 上 的变 化特 征 及规 律,并运用这些 规律 ,对未 采区进 行预 测、预报 ,正确 指导了 采掘 工程的 顺利 进行。  相似文献   

开滦林南仓井田岩浆岩侵入规律及找煤方向探讨     

丁立锋 《中国煤田地质》2004,16(Z1):12-13

通 过地 面钻孔 、井下 开采和 磁法 勘探,发现 井 田内 赋存 有 大量 的岩 浆 岩体 ,特 别是 西二 采 区发 育岩 床 ,使该 区可采 储量 急 剧减 少,严重 影 响了 井田 采 掘 工 程的 衔 接 ,使 矿 井 生产 处 于 被 动局 面 。 通过 对 岩 浆 岩侵 入 规 律 的深 入 研究,预 测了井 田岩 床的分 布范 围和面 积,对 区域找 煤以 及为矿 井生 产和可 持续 发展具 有现 实的指 导意 义。  相似文献   

Ambiguous Moment Tensors and Radiation Patterns in Anisotropic Media with Applications to the Modeling of Earthquake Mechanisms in W-Bohemia   总被引：3，自引：0，他引：3  

Rössler  D.  Rümpker  G.  Krüger  F. 《Studia Geophysica et Geodaetica》2004,48(1):233-250

Anisotropic material properties are usually neglected during inversions for source parameters of earthquakes. In general anisotropic media, however, moment tensors for pure-shear sources can exhibit significant non-double-couple components. Such effects may be erroneously interpreted as an indication for volumetric changes at the source. Here we investigate effects of anisotropy on seismic moment tensors and radiation patterns for pure-shear and tensile-type sources. Anisotropy can significantly influence the interpretation of the source mechanisms. For example, the orientation of the slip within the fault plane may affect the total seismic moment. Also, moment tensors due to pure-shear and tensile faulting can have similar characteristics depending on the orientation of the elastic tensor. Furthermore, the tensile nature of an earthquake can be obscured by near-source anisotropic properties. As an application, we consider effects of inhomogeneous anisotropic properties on the seismic moment tensor and the radiation patterns of a selected type of micro-earthquakes observed in W-Bohemia. The combined effects of near-source and along-path anisotropy cause characteristic amplitude distortions of the P, S1 and S2 waves. However, the modeling suggests that neither homogeneous nor inhomogeneous anisotropic properties alone can explain the observed large non-double-couple components.The results also indicate that a correct analysis of the source mechanism, in principle, is achievable by application of anisotropic moment tensor inversion.  相似文献   

Comparison of hydraulic geometry between sand‐ and gravel‐bed rivers in relation to channel pattern discrimination     

Jiongxin Xu 《地球表面变化过程与地形》2004,29(5):645-657

A comparison has been made between the hydraulic geometry of sand‐ and gravel‐bed rivers, based on data from alluvial rivers around the world. The results indicate a signi?cant difference in hydraulic geometry among sand‐ and gravel‐bed rivers with different channel patterns. On this basis, some diagrams for discrimination of meandering and braided channel patterns have been established. The relationships between channel width and water discharge, between channel depth and water discharge, between width–depth ratio and water discharge and between channel slope and water discharge can all be used for channel pattern discrimination. The relationship between channel width and channel depth can also be used for channel pattern discrimination. However, the accuracy of these relationships for channel pattern discrimination varies, and the depth–discharge relationship is a better discriminator of pattern type than the classic slope–discharge function. The cause for this difference has been explained qualitatively. To predict the development of channel patterns under different natural conditions, the pattern discriminator should be searched on the basis of independent or at least semi‐independent variables. The relationship between stream power and bed material grain size can be used to discriminate channel patterns, which shows a better result than the discriminator using the slope–discharge relationship. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

Seepage driving effect on deformations of San Fernando dams   总被引：2，自引：0，他引：2  

Xiang Song Li  Haiyan Ming   《Soil Dynamics and Earthquake Engineering》2004,24(12):979-992

In the process of flow deformation of an earth dam, the seepage force inside the dam plays a role as a driving force. The seepage force acts just like the gravitational force in terms of pushing soils away from their original locations after liquefaction is triggered. This paper draws attention to this seepage driving effect by presenting a set of fully coupled finite element analyses on the well-known San Fernando dams, with the objective of evaluating the impact of this seepage effect. The results indicate that while this effect is always there, its practical significance depends on a number of factors. In the case of the upper San Fernando dam, which experienced a significant, but restricted, downstream movement during the 1971 earthquake, the seepage driving effect was indeed significant. On the contrary, for the lower dam, which failed and slid into the upstream reservoir during the same earthquake, this seepage effect was relatively less pronounced. The detailed results of the analyses reveal the likely mechanisms of failure and deformation of the two dams and the likely cause behind the difference between their responses during the earthquake.  相似文献   

青藏高原影响亚洲夏季气候研究的最新进展   总被引：40，自引：6，他引：40  

吴国雄  毛江玉  段安民  张琼 《气象学报》2004,62(5):528-540

文中回顾了近 10a来吴国雄等在青藏高原影响亚洲夏季气候研究方面的最新进展。通过分析东西风交界面的演变证明 ,由于青藏高原的春季加热 ,亚洲季风区对流层低层冬季盛行偏东风转变为夏季偏西南风最早发生在孟加拉湾东部 ,与其相伴随的激烈对流降水出现在其东面。因此孟加拉湾东部至中印半岛西部是亚洲季风最早爆发的地区。同时也指出盛夏伊朗高原和青藏高原加热所激发的同相环流嵌套在欧亚大陆尺度的热力环流中 ,从而加强了东亚的夏季风 ,加剧了中西亚的干旱 ;并通过其所激发的波动对夏季东亚的气候格局产生重要影响。文中还比较了夏季南亚高压的伊朗模态和青藏模态性质的异同及其对亚洲夏季降水异常分布的不同影响。  相似文献   

鹤壁市春旱动态监测及分析     

王军王福州  周官辉郭魁英秦成福  杜滨鹤 《河南气象》2004,(1):17-18

利用鹤壁市淇县1971～2000年降水、底墒、蒸发资料，建立了适用于对春旱进行实时业务监测的动态模型；根据干旱指数大小确定春旱等级，并通过实例对比分析证实干旱指数在分析干旱动态演变过程中的作用。  相似文献   

Plastic flow strength of jadeite and diopside investigated by microindentation hardness tests     

Dorothe Dorner  Bernhard Stckhert 《Tectonophysics》2004,379(1-4):227-238

Microindentation hardness tests were performed on jadeite and diopside, being end members of the omphacite solid solution series. At temperatures between 300 and 750 °C, the hardness of jadeite ranges from 7.4 to 8.5 GPa, that of diopside from 4.9 to 6.1 GPa. Jadeite is significantly stronger than diopside in the low-temperature plasticity regime. Normalization of the hardness-derived yield stress with respect to the shear modulus considerably reduces the strength contrast. The normalized Peierls stress is identical for jadeite and diopside. This indicates that jadeite and diopside belong to the same isomechanical group. The hardness-derived yield stress for jadeite as well as for diopside is used to estimate flow law parameters for the low-temperature plasticity regime.  相似文献   

Dynamics of an active rock glacier (Ötztal Alps, Austria)     

Jana Berger  Karl Krainer  Wolfram Mostler 《Quaternary Research》2004,62(3):233-242

The rock glacier Innere Ölgrube, located in a small side valley of the Kauner Valley (Ötztal Alps, Austria), consists of two separate, tongue-shaped rock glaciers lying next to each other. Investigations indicate that both rock glaciers contain a core of massive ice. During winter, the temperature at the base of the snow cover (BTS) is significantly lower at the active rock glacier than on permafrost-free ground adjacent to the rock glacier. Discharge is characterized by strong seasonal and diurnal variations, and is strongly controlled by the local weather conditions. Water temperature of the rock glacier springs remains constantly low, mostly below 1°C during the whole melt season. The morphology of the rock glaciers and the presence of meltwater lakes in their rooting zones as well as the high surface flow velocities of >1 m/yr point to a glacial origin. The northern rock glacier, which is bounded by lateral moraines, evolved from the debris-covered tongue of a small glacier of the Little Ice Age with its last highstand around A.D. 1850. Due to the global warming in the following decades, the upper parts of the steep and debris-free ice glacier melted, whereas the debris-covered glacier tongue transformed into an active rock glacier. Due to this evolution and due to the downslope movement, the northern rock glacier, although still active, at present is cut off from its ice and debris supply. The southern rock glacier has developed approximately during the same period from a debris-covered cirque glacier at the foot of the Wannetspitze massif.  相似文献