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1.
《地质学报》1940,20(1)
From what we have seen during an area excursion in Lushan under theguidance of Proressor J. S. Lee we are led to belief that glacial features anddeposits can hardly be absent from the high-lying areas in western Hupeh. Ourreasoning is based on the similarity of the prevailing physiographic conditions and  相似文献   

2.
C.C.YEH 《地质学报》1944,(Z1):128-138
正 With 1 Plate. INTRODUCTION During the last five years, evidence of Quaternary glaciation has been gathered by different geologists from Hupeh, Hunan, Kuangsi, and Sikang. H. von Wissmann, in his paper on the Pleistocene Glaciation in China, has made  相似文献   

3.
It is well known that the mean can be an unsatisfactory estimator of a true value if data are a poor approximation to a normal distribution or are too few in number for a normal distribution to be adequately delineated. Unfortunately, this knowledge is not always implemented in the evaluation of analytical data. The median may be used occasionally because it is recognised to be less affected by discrepent data. However, there are other 'robust' estimators which can be better than the simple median. This note complements a previous paper by the writer (1).  相似文献   

4.
岩石节理面形态与水力特性研究   总被引:3,自引:1,他引:3       下载免费PDF全文
通过节理面粗糙度测量、张开度模拟、节理渗流试验及有限元数值分析,探讨了岩石节理复杂的水力特性。研究表明,节理渗流具有明显的不均匀性、各向异性及与变形耦合等性质,节理的渗透系数与法向应力之间呈负指数关系。  相似文献   

5.
Matheron (1971) proposed an approximation of the extension variance in IR. We propose in this note an extension of this formula in IR 2 , based on a MacLaurin formula. Its application is shown in an example, the estimation of the maximum depressional storage of a soil surface.  相似文献   

6.
节理是岩石中的裂隙,广泛分布于花岗石中,影响石材的成材性能以及石加工品的美感和耐用性。查明节理不仅直接控制石材的块度、荒料率,而且为石材的风化变色作用提供良好的构造环境,促使花岗石风化变色作用的加深及其效果的扩大化。多种形式的节理网在花岗石抛光面上形成低反射率的暗线、暗斑、暗区,降低花岗石的平均光泽度,影响光泽度的均一性和石加工品的质量。因此,节理的研究是正确评价、合理开发石材资源、提高石加工品质量的重要环节。  相似文献   

7.
《Geoforum》2011,42(5):iii
  相似文献   

8.
A new variant of the four-electrode system is proposed for geophysical resistivity investigations, particularly for profiling over conductive bodies. Model tank resistivity profiling experiments with Wenner, Schlumberger and the proposed T-shaped four-electrode arrays were carried out over a thin conducting vein type model to evaluate the efficacy of the new array. The proposed array appears to possess a larger response, a greater depth of investigation and a higher vertical resolution in detecting conducting bodies, as compared to the two-conventional arrays.  相似文献   

9.
Y.C.HSU 《地质学报》1943,(Z1):64-66
正 As stratigraphical data regarding breaks between the Triassic formations have accumulated as a consequence of recent research in the southern and western parts of Kuangsi, the appearance of a third note on the stratigraphical unconformities in this province to supplement previous papers on the sub  相似文献   

10.
初论分形地质学   总被引:12,自引:0,他引:12  
申维 《世界地质》1998,17(4):75-84
介绍了分形分布的概念和分布函数,分形的概念及其在地震,地貌,岩石,构造,矿床评价和矿产预测等地质研究领域的应用情况。  相似文献   

11.
岩石节理的渗流广义立方定理   总被引:29,自引:5,他引:29  
首先讨论了岩石节理的渗流立方定理及其适用条件,然后从渗流与变形耦合的角度,论述了节理的开度性质,并提出了适用于一般节理的渗流广义立方定理,最后用有限元数值模拟方法验证了广义立方定理。  相似文献   

12.
构造活动和气候变化的共同作用对象是地球表面,是通过不同的物理、化学和生物过程完成的.构造活动通过所形成的地形地貌影响到区域和局部地区的气候;而气候变化的反馈作用表现为风化、剥蚀夷平地形来促使高原和造山带均衡上升.列举了目前国内外重点研究的地貌单元实例,如地峡、青藏高原、安第斯山脉、湖盆、河流和海岸线(台地),介绍了国内外在该领域的研究动态.指出耦合系统的研究需要多学科交叉融合,地表地形是研究耦合系统的关键切入点,能精确定量测量地表地形的仪器设备和高精度的年代学方法也是不可缺少的.耦合系统的研究可以分为:构造事件时间序列、气候时间序列、地形演化的定量研究,以及耦合系统模式的建立.  相似文献   

13.
对综合钻探技术的内涵、原则、实质、特点、软硬件,目的及其发展途径,进行了探讨。  相似文献   

14.
Matheron (1971) proposed an approximation of the extension variance in IR. We propose in this note an extension of this formula in IR 2 , based on a MacLaurin formula. Its application is shown in an example, the estimation of the maximum depressional storage of a soil surface.  相似文献   

15.
李鹏云  陈晓国  张峰 《岩土力学》2012,33(Z1):223-228
假定桩土荷载传递函数为双曲线模型,分析T型刚性桩荷载传递机制,建立桩及桩帽下土体的竖向位移、竖向应力、侧摩阻力与深度之间的控制微分方程。采用微分方程近似解法,推导出相应的解析表达式。利用桩顶沉降作为已知条件进行求解,所得结果能够出反映T型桩荷载传递性状规律,即桩身轴力随深度增加而减小;桩身侧摩阻力随深度增加呈现出先增大后减小;桩土应力比与荷载有关。文中方法的计算值更接近于试验结果,可为工程设计提供理论基础。  相似文献   

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18.
A Shear Model Accounting Scale Effect in Rock Joints Behavior   总被引:1,自引:0,他引:1  
Understanding the scale effect on the mechanical behavior of a single rock joint is still very important in rock engineering. Rock joints can be classified into three different categories depending on their scale: the “micro scale” which is the scale of the asperities; the “meso scale” is the scale of the specimens tested in laboratory; and the “macro scale” which is the scale of the rock mass. The purpose of this paper is to propose an effective way to model rock joints at both the meso and macro scale. An original constitutive mechanical model, in which parameters are deduced from experimental results, has been developed. This model is then extended to simulate the discontinuities occurring at a larger size. At the macro scale, the constitutive modeling was carried out for both small and large relative displacements. Large displacements lead to substantial changes in dilation. For both cases, the peak shear stress vanishes for joints longer than 2 m.  相似文献   

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20.
INTRODUCTIONThemiddleandlowerreachesofChangjiangRiverareoneofthemainregionsinChinawhichischaracteristicofthewidespreaddistrib...  相似文献   

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