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1.
林修锬 《福建地质》2003,22(4):199-205
福建省共有3条省界、191条县界、全长12000km。历经5年~6年的勘界工作,形成了大量的图形、文本、表格、照片等珍贵资料,其种类繁多、关系复杂。为满足对这些资料进行有序存储、管理和提供服务,以MAPGIS、MAPINFO数据采集,SQL Sever2000数据库为平台,Delphi语言作相应的开发,实现数据采集.编辑和数据管理。建立“福建省行政区域信息管理系统”。  相似文献   

2.
为配合实施最严格的水资源管理制度,水利部水文局组织开展了《全国省界断面水资源监测站网规划》编制。本文依据规划报告主要成果,明确了省际河流、省界站概念,总结了目前水文站网为水资源管理服务存在的主要问题;对省界站的特点进行了分析,结合应用需求,着重对规划原则、布设原则、选取原则及主要成果进行了介绍,规划全国省界站共841处,其中利用现有测站359处,规划新建测站482处。对规划站网成果进行了初步分析评价,全国省级行政区界的平均入境水量监测控制率约为86%,出境水量监测控制率约为88%,基本满足水资源用水总量量化考核需要,其成果填补了我国水文水资源站网规划的空白。  相似文献   

3.
Slater PB 《GeoJournal》1982,6(5):477-480
In contrast to results for several other nations, hierarchical regionalizations based upon 1960 Philippine lifetime migration do not indicate that islands act as migration regions — groups of provinces, relatively self-contained with respect to migration flows. Inter-island links seem to be more important than intra-island ties. Northern Luzon, the Bicol Peninsula and the Southern Philippines are among the regions that appear. Manila and its suburban province of Rizal are exceptional both for the breadth and strength of their interprovincial migration ties.  相似文献   

4.
Present interest in environmental problems which are international, interstate or interprovincial in scope is drawing attention to the necessity for ecological regionalizations that will serve as a basis for intraregional transfer of experience. The major efforts at ecological regionalization by the national governmental agencies are described and compared. Although similar concepts have evolved in both countries, different systems of units have been developed for defining and mapping ecosystems at the regional scale. Before any regionalization is used it should be thoroughly tested, and modified if necessary.  相似文献   

5.
《International Geology Review》2012,54(12):2150-2164
For the basis of interprovincial correlation the Pleistocene formations and volcanics in Kyushu were re-examined stratigraphically and the revised results are presented here. The following five areas were chosen for the stratigraphic revision; they are the Oita district, Nalcatsu district, southern half of Nagasaki Prefecture, marginal area of northern Kagoshima Bay, and the Miyazaki district. The Pleistocene formations and volcanic rocks are extensively developed in the above-mentioned areas and those in the respective areas serve as the standard section for a part of the Pleistocene stratigraphy. Consequently the systematic study on the geology in these areas gives a general outline of the stratigraphic correlation of the Pleistocene units in Kyushu. — Author.  相似文献   

6.
严寒地区路堑边坡破坏机理及稳定计算分析   总被引:2,自引:0,他引:2  
冯守中  闫澍旺  崔琳 《岩土力学》2009,30(Z1):155-159
内蒙古省际通道新林北至扎兰屯段一级公路修建过程中,一些局部路堑边坡出现了较严重的边坡滑塌现象。目前公路行业的路基设计施工规范中尚没有涉及高寒地区路堑边坡的设计施工方法,也缺乏此类地区路堑边坡的稳定性设计评价标准。为此在进行了大量调研工作的基础上,对路堑边坡的破坏机理进行了分析,提出了确保公路路堑边坡稳定的有效措施及相应的计算方法,成果可为其他类似工程借鉴参考。  相似文献   

7.
The 1981 census has motivated this study, outlining changes in Spanish population patterns during the decade 1970–1981. For migration patterns the year 1975 may have been a significant turning point. As a consequence of the economic recession in the western world emigration is coming to an end; the interprovincial migration, too, is declining rapidly. In some provinces a remarkable change can be observed in the direction of migration flows. After more than 25 years the industrial regions of Spain are now losing population by migration, whereas rural provinces of the central highlands and of Andalusia exhibit some growth by migration for the first time. This is a result of return migration from abroad as well as from the industrial regions of Spain. For natural change three important dynamics overlap. First, a marked increase in natural growth from North to South is found. This pattern of natural change is strengthened or weakened regionally by age-specific selective migration. Lastly, both dynamics have recently been dominated by an overall decline of the crude birth rate in all of Spain since 1970.  相似文献   

8.
The Bathonian ammonite assemblages have been previously poorly recorded in Kutch. The present study has unearthed a rich array of ammonite taxa ranging from the Middle to Upper Bathonian. While Oxycerites Rollier (1909) is a new record from Kutch, the oldest occurrence of Choffatia Siemiradzki (1898) has been found from the Middle Bathonian horizon. Oxycerites cf. orbis (Giebel) is a zonal index of the Late Bathonian in other areas and thus facilitates interprovincial correlation. Besides, palaeobiogeographic and stratigraphic distribution of many species have been modified based on new information. For example, macrocephalitin species, i.e., Kamptokephalites cf. etheridgei Spath (1928), Macrocephalites bifurcatus transient intermedius Spath (1928), M. cf. mantataranus Boehm (1912) were previously known from West Pacific, Indonesia have been now found in Kutch. Gracilisphinctes Buckman (1920) has been previously known to occur during the Middle Bathonian time, the present work extends its stratigraphic distribution up to the definite Upper Bathonian horizon. Procerites hians (Waagen) an endemic species in Kutch previously known from the Upper Bathonian beds, its stratigraphic range has been extended down to the Middle Bathonian.Detail taxonomy of the newly obtained taxa has been done and in many cases sexual dimorphism has been recognized.  相似文献   

9.
The Bathonian ammonite assemblages have been previously poorly recorded in Kutch. The present study has unearthed a rich array of ammonite taxa ranging from the Middle to Upper Bathonian. While Oxycerites Rollier (1909) is a new record from Kutch, the oldest occurrence of Choffatia Siemiradzki (1898) has been found from the Middle Bathonian horizon. Oxycerites cf. orbis (Giebel) is a zonal index of the Late Bathonian in other areas and thus facilitates interprovincial correlation. Besides, palaeobiogeographic and stratigraphic distribution of many species have been modified based on new information. For example, macrocephalitin species, i.e., Kamptokephalites cf. etheridgei Spath (1928), Macrocephalites bifurcatus transient intermedius Spath (1928), M. cf. mantataranus Boehm (1912) were previously known from West Pacific, Indonesia have been now found in Kutch. Gracilisphinctes Buckman (1920) has been previously known to occur during the Middle Bathonian time, the present work extends its stratigraphic distribution up to the definite Upper Bathonian horizon. Procerites hians (Waagen) an endemic species in Kutch previously known from the Upper Bathonian beds, its stratigraphic range has been extended down to the Middle Bathonian.Detail taxonomy of the newly obtained taxa has been done and in many cases sexual dimorphism has been recognized.  相似文献   

10.
冻土钻孔内温度分布的相关参数研究   总被引:1,自引:0,他引:1  
介绍了冻土钻孔内温度分布研究的理论基础,其中主要讨论了冲洗介质的质量流量、钻杆杆壁的导热系数、岩石同冲洗介质的热交换强度系数与不稳定热交换系数,以及孔底冲洗介质温度升高值的确定.结合实例分析了边界条件常数、钻杆导热系数与钻杆内和环状间隙中的传热系数对孔内温度分布的影响.孔底温度的上升主要与冲洗介质的质量流量、其初始温度及热容量、孔底碎岩消耗的功率以及钻头结构与物性有关.  相似文献   

11.
李红坡  梅国雄  肖涛  陈征 《岩土力学》2020,41(5):1560-1566
在软基处理工程中,经常出现竖井打设变密而地基固结效率降低的现象。鉴于此,建立了重叠涂抹区内土体水平向渗透系数的分布函数,给出了涂抹区重叠时竖井地基超静孔压和平均固结度的解析解。通过分析不同工况下竖井地基固结度随竖井间距的变化情况,探究了竖井间距减小而地基固结效率不增反减的成因。最后,探讨了涂抹作用和井阻作用对竖井最小临界间距的影响。结果表明:相邻竖井涂抹区重叠是竖井地基中出现竖井最小临界间距的根本原因。涂抹作用越大,则竖井最小临界间距越大;具体表现为当地基扰动程度增大时或涂抹区半径增大时,竖井最小临界间距随之增大。井阻作用越大,则竖井最小临界间距越小;具体表现为当竖井渗透系数减小时、竖井长度增大时或竖井半径减小时,竖井最小临界间距随之减小。  相似文献   

12.
考虑主应力轴旋转的基坑开挖应力路径研究   总被引:2,自引:0,他引:2  
应宏伟  李晶  谢新宇  朱凯  周建 《岩土力学》2012,33(4):1013-1017
首先对应力路径的概念进行丰富和扩展,提出考虑主应力轴旋转的三维应力路径,然后采用数值方法,对基坑开挖过程中的应力路径进行了深入分析,研究了基坑内外各种应力路径及其规律,结果表明:开挖过程中无论横向还是竖向,应力路径都表现出卸荷特性,且坑内卸荷量大于坑外卸荷量,使得坑内应力变化及主应力轴旋转较坑外大;随着离基坑中心距离的增大,坑内应力变化减小,主应力轴旋转趋缓;开挖过程对坑外应力变化及主应力轴旋转的影响随离围护墙距离的增大而减小。坑内应力路径总体表现为平均压应力p减小,广义剪应力q减小,主应力轴偏转角? 增大;坑外应力路径总体表现为p减小,q增大,? 增大。最后归纳出基坑开挖过程中坑内与坑外的典型应力路径,以指导基坑工程实践设计分析和室内试验模拟。  相似文献   

13.
湖南郴州柿竹园超大型钨多金属矿床的成矿复杂性研究   总被引:6,自引:0,他引:6  
用非线性科学和复杂性理论对湖南郴州柿竹园超大型钨多金属矿床的成矿复杂性进行系统、深入的研究 ,以成矿作用与时空结构是一切矿产资源的本质与核心的自然哲学理念为根本立足点 ,从一种新的视角 ,就矿床的动力学属性、矿床的物质成分与结构、矿床的地质学场和成矿系统的演化四大相互联系的范畴 ,对矿产资源进行再认识 ,提出了矿床的新定义 ,并较深刻地揭示了矿床的动力学属性、成矿物质高度多样化和复杂性及其超常规模集成、矿田成矿分带的内部结构、矿床地质学场的时空分形结构、成矿系统时间演化的长期性和成矿过程的多期多阶段性以及成矿作用的发生和矿床形成的分形生长机制等方面的复杂性与动力学本质。项目成果将矿床学的研究提高到非线性科学和复杂性理论的层次 ,提供了如何应用这种理论和方法对矿床的成矿复杂性进行研究的实例 ,也是第一作者所提出的关于成矿系统复杂性的新成矿理论与方法论“成矿动力系统在混沌边缘分形生长”的具体化及其进一步深化。沿着这一研究方向的不断开拓将可使传统矿床学向精确科学跨越。  相似文献   

14.
坡体内不同部位结构面间岩桥断裂扩展导致了反倾层状岩坡的破坏。为研究坡体内非贯通性裂缝断裂扩展对坡体演化的控制作用,以苗尾水电站右坝肩倾倒变形体为地质原型,开展含多组非贯通性裂缝的反倾层状岩质边坡离心模型试验,分析反倾层状岩质边坡内非贯通性裂缝变形特性。结果表明:(1)坡体内含非贯通性裂缝的岩层断裂最终呈现为裂缝间岩桥贯通、缓倾裂缝与上岩层贯通、陡倾裂缝与下岩层贯通、陡倾裂缝与缓倾裂缝端口处贯通及非裂缝处岩层发生断裂等5类裂缝断裂模式,并以裂缝间岩桥贯通为主要断裂模式;(2)基于断裂力学并结合裂缝断裂叠加原理,主折断面处岩层的不稳定系数在坡高1/3处最小,并向坡脚和坡顶两侧逐渐变大,而应力强度因子由坡高1/3处向坡脚和坡顶处逐渐变小;(3)裂缝的断裂扩展控制着坡体演化,并受裂纹率及裂缝周围的尖端应力场影响较大。在坡体演化初期,以坡体后缘压缩沉降和局部岩层裂缝压剪破坏为主,岩层倾角发生较大变化,呈现由坡体上部往下逐级变大的趋势;演化中期,坡体后缘裂缝扩展形成主折断面,坡体中上部岩层角度变化较大,裂缝断裂数目的继续增加;演化末期,裂缝断裂数目保持平稳,主要以断裂岩层的位置重分布为主要变形特征...  相似文献   

15.
泥石流流体性质不仅决定了泥石流的类型,而且是研究泥石流动力学特征、泥石流治理、泥石流危险性评价等方面的基础。通过分析泥石流堆积物颗粒粒度特征和一系列的定量指标可以分析泥石流流体性质。由于后期洪水作用下泥石流堆积物颗粒粒度特征发生了变化,再加上颗粒粒度分析中取样等因素影响使泥石流堆积物颗粒粒度分析结果难以反映泥石流流体性质。因此,泥石流流体性质不能仅仅依据泥石流堆积物颗粒粒度特征来确定,而应采用综合分析研究方法来确定泥石流流体性质。本文以关家川沟为例,采用堆积物颗粒粒度分析与相关定量指标相结合的方法,综合分析研究了关家川沟泥石流流体的性质。该分析研究方法对研究泥石流流体性质具有实际的工程意义。  相似文献   

16.
梅冥相 《地质学报》2014,88(10):1944-1969
发生在中、晚三叠世之交的印支运动,在中国南方表现为以下构造事件:1秦岭-大别造山带的形成与隆升,记录了华北板块与华南板块的对接碰撞;2中国南方东南部1300km宽的陆内造山带的强烈作用,以及由此造成的前陆褶皱逆冲带的北西向迁移。在上述构造事件的结果,结束了扬子地台自埃迪卡拉纪以来以作为一个稳定的古地理单元而且大多数时间发育浅水碳酸盐岩的沉积历史。在扬子地台消亡之后形成一个特别的上扬子前陆盆地(或四川前陆盆地),其中堆积了以河流沉积为特征的须家河组及其相关地层。以河流沉积为特征的须家河组及其相关地层,在川西地区覆盖在马鞍塘组台地碳酸盐岩和小塘子组陆棚至滨岸相砂页岩地层之上,向东、向南逐渐超覆尖灭,从而形成了一个特殊的上三叠统层序地层格架,这个特殊的层序地层格架记录了扬子地台的消亡和上扬子前陆盆地的形成和发育过程。就像黔西南地区在中三叠世台地边缘再生的晚三叠世前陆盆地以及该盆地中填充的特别的上三叠统一样,上扬子前陆盆地上三叠统层序地层格架,尤其是河流沉积为特征的须家河组特别的沉积趋势(从相对集中发育煤层的高可容纳空间低能河流沉积、演变到河道砂岩聚合作用为特征的低可容纳空间高能河流沉积的序列,所组成的沉积层序)所组成的冲积构架,以及逐渐从西向东、从北向南的逐渐超覆尖灭的空间分布,不但是了解扬子地台消亡和上扬子前陆盆地形成的重要物质记录,而且代表了前陆盆地充填序列中一种较为特别的河流相层序地层序列。  相似文献   

17.
We examine the formation of the Michigan Basin in terms of elastic flexure of the lithosphere. The shape of the flexure accurately determines the flexural rigidity of the lithosphere and the lateral extent of the load responsible for the flexure. The amplitude of differential subsidence then gives the magnitude of the load. Gravity anomalies in the southern peninsula of Michigan further restrain the dimensions of the load. We propose a model for the formation of the Michigan Basin involving mantle diapirs. We suggest that the first stage in its evolution was diapiric penetration of the lithosphere by hot asthenospheric mantle rock to the vicinity of the Moho. The heating of the lower crust by these hot rocks caused the transformation of lower crust, meta-stable gabbroic rocks to eclogite. Initially the lighter mantle rocks nearly balanced the heavier eclogite. As the mantle rocks cooled by conduction, the basin subsided under the load of the eclogite. The thermal contraction mechanism is supported by evidence that the flexural rigidity of the lithosphere increases with time. This is the effect of thickening of the elastic lithosphere as cooling progresses.  相似文献   

18.
付广  梁木桂 《地质学报》2022,96(2):691-698
为了研究含油气盆地下生上储式受断裂控制油气分布规律,在断裂输导向遮挡油气转换时期及其与油气运聚成藏之间关系研究的基础上,通过确定断裂在盖层内填充物排替压力随时间变化关系和盖层之下储层岩石排替压力随时间变化关系,取二者相等时所对应时期,建立了一套断裂输导向遮挡油气转换时期的厘定方法,并将其应用于渤海湾盆地南堡凹陷老爷庙构...  相似文献   

19.
Assuming that the observed periodic variations of pulsar emission are due to the free precession of the spin axis, we investigate the evolution of the rotation of a two-layer neutron star using the Hamiltonian method of Getino. We model the dynamical characteristics of a rotating neutron star using the observed variations of the emission of seven pulsars. We estimate the dependence of the period of the Chandler wobble, the period of precession of the spin axis, and the dynamical ellipticity of a neutron star on the model used to describe the super-dense neutron matter and the mass of the star.  相似文献   

20.
三维矿床地质模型的不确定性对矿山生产决策有着重要影响,正确地对矿床地质模型进行不确定性分析可以对其本身和在其基础上所做的决策作出科学评价。矿床地质模型的不确定性主要来自于建模数据和插值方法的不确定性。通过对建模数据的产生、处理过程的分析,利用处理不确定性问题的理论和方法建立建模数据的不确定性模型。通过对建模方法产生的理论误差和实测误差进行量化,实现对建模方法不确定性的定量描述。将建模数据的不确定性和建模方法的不确定性进行叠置分析,建立矿床模型的不确定性模型。以内蒙古自治区某煤矿的地质资料为例,通过不确定性分析,建立了该矿的不确定性三维矿床地质模型。   相似文献   

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