Quantitative study of landscape patterns in homogenous carbonate rock distributed regions in Guizhou     

Qiu TAN Shijie WANG Yangbing LI 《中国地球化学学报》2006,25(B08):174-175

With the utilization of GIS software, research is conducted on （a） the characteristics of cells, fragmentation, and patch fractal of landscape based on homogenous carbonate rocks in Guizhou; （b） causes of the formation of these characteristics. It has been found that under the influence of lithology, the landscape of the study region as a whole shows consistency, yet embodies distinct diversity inside. The consistency is embodied in the following aspects： （a） the preponderant landscape consists of bushes and small woods; （b） secondary landscape is characteristic of forests and grounds covered with grass; （c） of all the patches making up the study area small patches are in the majority, with positive-skewed distribution of patches-as a result, steep peaks are characteristic of the charts showing the distribution of patches. The factor of scale is not taken into account in the study of patches. The shapes of patches tend to be regular with strong disturbances from human activities, and consequently, the values of fractal dimensions of landscape types tend to get smaller. The fragmentation of patches is more apparent in landscape under influence of human activities than the one without these disturbances. Compared with regions characteristic of homogenous dolomite, the characteristics of homogenous limestone areas are described as follows： （a） low utilization rate of water resource; （b） uneven distribution of diversified landscape; （c） weak resistance against disturbances from human activities; （d） the continuous degradation, ever-increasing fragmentation, intensification of spatial heterogeneity, and the deteriorating stability of landscape.  相似文献   

PDC钻头切削齿破岩载荷规律的分析     

许爱 《探矿工程》2006,33(7):59-61

对PDC钻头冠部形状及不同的布齿密度和切削齿在不同的磨损状态下对PDC钻头切削齿受力的影响进行了分析；用相邻的3个切削齿之间的关系(不同的切削齿与切削齿之间的径向距离和切削齿之间的高度差)来分析PDC钻头冠部形状和切削齿布齿密度对切削齿受力的影响，以及将切削齿的磨损状态简化成与切削齿在钻头上装配方向垂直的平面来分析切削齿磨损状态对切削齿受力的影响。  相似文献   

顶管施工中顶力与顶程关系及其影响因素分析     

向安田丁文其  朱合华 《探矿工程》2006,33(10):29-31,34

以上海某长距离急曲线顶管工程为例，通过现场实测4节管段顶进过程中的顶力，研究了顶力随顶程的变化规律，系统分析了顶进过程中顶力的主要影响因素，得到了一些有用的结论。  相似文献   

The Usage of Ground Penetrating Radar (GPR) in Designing Blast Pattern     

G. U. Aldas  S. Kadioglu  E. Ulugergerli 《Rock Mechanics and Rock Engineering》2006,39(3):281-290

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R＆D投入的区位模式与区域经济发展   总被引：2，自引：1，他引：2  

姜怀宇  李铁立 《地理科学》2006,26(1):13-19

基于对中国R＆D投入的区位模式的实证检验，从投入一产出绩效的角度认为集中投入的区位模式具有较强的适宜性。利用聚类分析技术，按照R＆D的投入强度和及其对经济的带动效应、科技化效应、产业化效应将中国各省区划分为6类地区，具有代表性的是科技化模式和产业化模式。其中前者适合于技术存置较高的少数地区，而后者具有较强的借鉴意义。  相似文献   

21世纪中国主要粮食产区的空间格局特征   总被引：1，自引：0，他引：1  

殷培红  方修琦  田青  MA Yuling 《地理学报(英文版)》2006,16(4):396-404

Grain production is an important issue for the national economy and the livelihood of the Chinese people. It serves as the foundation of national development and social stability. China is a major grain producer as well as a major grain consumer. The grai…  相似文献   

Fan beheading and drainage diversion as evidence of a 3200-2800 BP earthquake event in the Esmeraldas-Tumaco seismic zone: A case study for the effects of great subduction earthquakes   总被引：1，自引：0，他引：1  

J.F. Dumont  E. Santana  F. Valdez  J.P. Tihay  P. Usselmann  D. Iturralde  E. Navarette 《Geomorphology》2006,74(1-4):100-123

The San Lorenzo area belongs to the Esmeraldas–Tumaco seismic zone where some of the strongest earthquakes of South America occurred during the 20th century. This paper provides evidence for a succession of geomorphic changes characterized by the disruption of the Quaternary drainage network and the reshaping of the Cayapas–Santiago estuary. The rise of the La Boca uplift bordered by the La Boca and San Lorenzo faults is responsible for the southward diversion of the Palabi, Tululbi, Bogotá and Carolina rivers toward the Santiago and Cayapas rivers. The increase of the discharge directed to the Cayapas River generated the change of the channel pattern downstream from the confluence, and the avulsion of a new estuary through the coastal plain. According to the dating of beach ridges the avulsion occurred in the period 3200–2800 BP. This period corresponds also to a faster accretion of the beach ridge margin, interpreted as a response to a small uplift of the shore. The coherency of the three morphologic evidences—diversion of drainage network, avulsion and increase of coastal accretion—suggest a unique morphotectonic event, in relation with the activity of the Esmaraldas–Tumaco seismic zone. The opening of a direct communication through the mangrove margin may have brought favorable conditions for the development of the La Tolita archaeological site after 3000 BP.  相似文献   

华南地区晚二叠和晚三叠世煤中稀土元素特征研究   总被引：2，自引：0，他引：2  

杜美霞  庄新国 《中国煤田地质》2006,18(2):22-26

在华南地区贵州六盘水、江西乐平、露庆和湖北黄石矿区晚二叠和晚三叠世煤层的稀土元素ICP—MS分析数据的基础上，系统研究了研究区煤中稀土元素的含萤分布特征、赋存特征、配分模式以及地质控制因素。含量分布表明晚二叠世稀土元素含量总体高于晚三叠世；煤中稀土元素与灰分成正相关关系，部分煤样品由于有富稀土元素的重矿物组合的存在而出现稀土元素的异常高值；同一矿区、同一时代煤中稀土元素的配分模式具有一定的相似性，而不同地区同一时代和同一地区不同时代煤中稀土元素的配分模式具有较大差异；煤的沉积环境，煤中无机矿物组成以及海水的影响是控制煤中稀土元素含量和配分模式的主要地质因素。  相似文献   

淮北煤田孙庄勘探区煤层气赋存规律及影响因素分析     

樊爱英 《中国煤田地质》2006,18(5):25-27

通过对淮北煤田孙庄勘探区地质构造、沉积特征、煤层煤质及煤层气赋存特征的分析，研究认为有利于本区煤层气赋存的主要因素是较大的埋藏深度、较高的壳质组＋镜质组、较高的变质程度、较大的煤层厚度、低透气性的盖层、较缓的地层倾角和封闭性较好的构造条件，推测煤田深部可能具有一定工业价值的煤层气资源。  相似文献   

基于GIS/MIS/OA的短周期工业原料林经营模式研究   总被引：3，自引：0，他引：3  

唐代生  边馥苓  朱志正  李重立 《测绘信息与工程》2005,30(1):12-14

提出了短周期工业原料林经营模式的概念,探讨了短周期工业原料林经营模式的体系结构、子系统功能和主要林业数表类型,说明其与GIS/MIS/OA系统集成的必然趋势,并以岳阳纸业股份公司的纸浆原料林为例进行了实例分析。  相似文献