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1.
This research paper analyses the grain-size characteristics of the Quaternary deposits at Xingshan near Siping, Jilin province in China by employing graphic measures to study the grain size distribution and its mode of transport and deposition. The Quaternary deposits at Xingshan lie unconformable on Cretaceous rocks made of siltstone, mudstone and sandstone. The average grain size is between 8.06 to 8.55Φ (0.002 6 ～0.003 7 mm). The Quaternary deposits at Xingshan mainly compose of very fine silt to clay. The compositions of the grade are clay 63% and silt 37%. The clay size components are weathered debris transported and deposited by flowing water from the SE highlands or hills to the low lying NW Xingshan plains whereas the silty components accumulated by aoelian process. The Quaternary deposits at Xingshan accumulated in the middle and late Pleistocene interglacial periods from (459.12～39.03) ka to (88.92～7.56) ka. The standard deviation ranged from 0.96 to 1.36Φ, indicating that the sediments are moderately to poorly sorted, Coefficient of skewness ranged from 0.16～0.31 with an average skewness of 0.218, (Positively skewed towards fine). Kurtosis values (0.84～1.05) from the grain size distribution and visual inspection of the frequency curves indicate platykurtic to mesokurtic curves and unimodal to bimodal grain-size distribution. The type of deposit formation is sand dune and the source is at a distal from its provenance. 相似文献
2.
In order to understand the process of surface erosion and acquire basic data of conditions on hillslope without vege tation, a sprinkling experiment is conducted on a bare slope in Mt. Tanakami in the central part of Japan. Based on the mea surements of runoff, mean soil erosion depth, and sediment yield, etc. , the results suggest the following characteristics in the process of surface erosion in the experimental area. (1) The occurrence of sediment discharge is interrupted; (2) Surface runoff is a saturated overland flow; (3) The mean soil erosion depth is thick compared with other areas in Mt. Tanakami;(4) Sediment discharge process is detachment- limited. 相似文献
3.
鞍山市铁矿矿山地质灾害形成条件及对策研究 总被引：4，自引：2，他引：4
矿山地质灾害较其它地质灾害相比有其独特性。在鞍山铁矿区，排土场沉降不仅与采矿引起的地下水位下降有直接的联系，还与松散细粒土层、活动断裂有关；滑坡、泥石流地质灾害与地形地貌、水源条件及构造有一定的关系，更重要的是采矿活动产生的废石废渣为其提供了大量的物源；尾矿库灾害主要表现为：洪水漫顶、尾矿砂液化破坏、尾矿坝渗漏及管涌溃堤、尾矿坝滑塌破坏等。本文简要分析了鞍山市铁矿山主要存在的地质灾害类型(排土场地面沉降、滑坡、泥石流及尾矿库地质灾害)和形成条件并提出了防治地质灾害的对策。 相似文献
4.
吴锡奎 《中国地质灾害与防治学报》2001,12(2):80-82
利用Internet技术构建本系统的局域网络(Intranet),将信息管理与交流建立在统一的平台上,为地质环境监测信息的管理、综合运用和信息共享提供了廉价、高效的技术手段.作者结合工作实践,用一个实例详尽地阐述了基于WindowsNTServer的地质环境监测信息计算机网络的建立过程,它以提供WWW、FTP、E-Mail等计算机网络服务为基础,阐述了系统软件安装、所需服务器配置的详尽技术细节,从而为一个支持远程拨号上网的内部计算机网络建立,提供一个完整、可供借鉴的解决方案. 相似文献
5.
This paper presents an iterative, incremental pressure‐stabilized fractional step algorithm for coupled hydro‐mechanical problems with mixed formulations of the displacement–pressure ( u –p) model in saturated soil dynamics that allows the use of finite elements with equal low order of interpolation approximation of u and p. In comparison with the original fractional step algorithm, the distinct features of the proposed algorithm lie in its enhanced stability owing to the introduction of both an iteration procedure and a finite increment calculus (FIC) process into the algorithm. The introduction of the iterative procedure makes the velocity term satisfy the momentum conservation equation in an implicit sense and allows much larger time step sizes to be used than those limited in existing explicit and semi‐implicit versions of the algorithm. The introduction of the FIC process removes the dependence of the stability of the proposed algorithm on the time step size, as a result it allows to using the incremental version of the algorithm and evades the minimum time step size requirement presented in the existing versions of the fractional step algorithm that restricts the application of the algorithm to saturated soil dynamics problems with high frequencies. Numerical experiments demonstrate the effectiveness and improved performance of the proposed iterative pressure‐stabilized fractional step algorithm. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
6.
Liu Zhigang Wang Zhikang Zhang Ruoxiang Sun Xikui Wenzheng Shang 《Geotechnical and Geological Engineering》2022,40(11):5425-5436
Geotechnical and Geological Engineering - To study the influence of changes in the coal seam mechanical characteristics at depth on the stress relief effect of a borehole, this paper established... 相似文献
7.
Maxwell A Boateng Xikui Wang 《东北亚地学研究》2006,9(1):30-39,48
This research paper analyses the grain-size characteristics of the Quaternary deposits at Xingshan near Siping, Jilin province in China by employing graphic measures to study the grain size distribution and its mode of transport and deposition. The Quaternary deposits at Xingshan lie unconformable on Cretaceous rocks made of siltstone, mudstone and sandstone. The average grain size is between 8.06 to 8.55Ф （0. 002 6 0. 003 7 mm）. The Quaternary deposits at Xingshan mainly compose of very fine silt to clay. The compositions of the grade are clay 63 % and silt 37 %. The clay size components are weathered debris transported and deposited by flowing water from the SE highlands or hills to the low lying NW Xingshan plains whereas the silty components accumulated by aoelian process. The Quaternary deposits at Xingshan accumulated in the middle and late Pleistocene interglacial periods from （459.12 - 39.03 ） ka to （88.92 - 7.56 ） ka. The standard deviation ranged from 0.96 to 1.36%, indicating that the sediments are moderately to poorly sorted, Coefficient of skewness ranged from 0.16 - 0.31 with an average skewness of 0. 218, （Positively skewed towards fine）. Kurtosis values （0.84- 1.05） from the grain size distribution and visual inspection of the frequency curves indicate platykurtic to mesokurtic curves and unimodal to bimodal grain-size distribution. The type of deposit formation is sand dune and the source is at a distal from its provenance. 相似文献
8.
赵锡奎 《沉积与特提斯地质》1991,11(6):41-47
上扬子地区下二叠统碳酸盐岩中,不同程度地发育一种中—粗晶白云岩或云灰岩,人们俗称为“糖粒状”白云岩。80年代以来,其成因多被解释为淡水透镜体模式形成的混合水白云化。笔者1987—1988年对黔中织金、清镇、黔西等地十余个剖面详细观察和室内薄片、扫描电镜、碳、氧同位素、有序度、包体均一温度的综合研究,结合该区地质演化分析,认为这类白云岩的成因当属埋藏过程中受构造活动影响的热液作用所致。一、“糖粒状”白云岩的产状与分布规律黔中地区下二叠统中—粗晶白云岩或云灰岩,多以似层状、巨厚块状(可达40m)、斑 相似文献
9.
在以遥感图像、地质、地球物理等资料分析东北地区构造骨架的基础上，结合天然地震、地应力测量和现代地壳形变等资料的研究，提出北东向构造是我国东北现今主导构造，并讨论了现代构造应力场及地震发生的构造环境。 相似文献
10.
从遥感地质角度，结合地质、地貌来研究东北地区新生代地壳水平运动特征、规律。东北新生代地壳水平运动表现为水系变形、山体错移、新构造被错断、地质体错移变形等。呈现出其运动的广泛性、协调性、多期性、继承性和持续性。该区的应力场在新生代期间多次改变，并控制了主要断裂的活动方式。 相似文献