伊利石结晶度及其在低温变质研究中若干问题的讨论   总被引：4，自引：0，他引：4  

王河锦  陶晓风  M.Rahn 《地学前缘》2007,14(1):151-156

文中介绍与伊利石结晶度相关的伊利石矿物新的定名方案;讨论了伊利石结晶度的结晶学基础与Scherrer方程式的关系;讨论了三个重要的伊利石结晶度指数Weaver、K櫣bler和Weber指数的关系,并介绍推导的Weaver、K櫣bler和Weber指数的理论关系式;评价了衍射仪测量条件对结晶度数值的影响和三套伊利石结晶度标样的作用以及成岩带、变质带与葡萄石-绿纤石相、沸石相、绿纤石-阳起石亚相对比的依据。建议(1)停用绢云母一词;(2)建立可供各实验室使用的具有晶体结构和晶体化学参数和多型参数的伊利石结晶度标样;(3)建议多开展规范的可进行国际对比的低温变质研究,划分出与国际上一致的成岩带和近变质带,不仅利于低温变质作用理论的研究,而且由于成岩带到近变质转变带是重要的煤气油的生成带,也利于中国煤气油资源的勘探与开发,利于国民经济的长远持续发展。  相似文献   

空间方向关系形式化描述模型研究   总被引：12，自引：1，他引：12  

闫浩文  郭仁忠 《测绘学报》2003,32(1):42-46

空间方向关系形式化描述模型是空间关系研究的难点和重点，目前尚无完善的模型出现，因此进行其模型的研究意义重大。首先论述运用平面目标Voronoi图描述方向关系在理论上的可行性；然后详细阐述基于Voronoi图的空间方向关系形式化描述模型建立；为了验证模型的正确性，给出几个典型的算例；最后指出模型的优、缺点。  相似文献   

Foreshore and seabed policy: A Māori perspective     

Angeline Greensill 《New Zealand geographer》2005,61(2):158-160

Abstract: The comment provides a Māori perspective on the Foreshore and Seabed Act. In contrast to the western view, Māoris understand their relationship with the coast in ways that are holistic, intertwined and unbounded. The Act disrupts the wairua or spirit of place, impacting on relationships that have been nurtured by whānau and hapū over time.  相似文献   

Faults linkage, damage rocks and hydrothermal fluid circulation: Tectonic interpretation of the Rapolano Terme travertines (southern Tuscany, Italy) in the context of Northern Apennines Neogene-Quaternary extension     

Andrea brogi 《Eclogae Geologicae Helvetiae》2004,97(3):307-320

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国际河流流域开发中的利益冲突及其关系协调--以澜沧江-湄公河为例   总被引：5，自引：0，他引：5  

陈丽晖  曾尊固  何大明 《世界地理研究》2003,12(1):71-78

本文以澜沧江—湄公河为例，介绍了流域自然条件区域特征、重要的开发行动，分析了各流域国的关注点，及其流域开发中存在的国家间利益冲突，部门间利益冲突，国家、地方与个体之间的利益冲突，提出冲突存在的危害和冲突解决的可行性，并就澜沧江—湄公河流域开发中需要协调的利益关系提出具体建议。  相似文献   

The changing role of border zones in the transforming economies of East-Central Europe: The case of Poland     

Tadeusz Stryjakiewicz 《GeoJournal》1998,44(3):203-213

The geopolitical and socio-economic changes in East-Central Europe that started at the beginning of the 1990s has brought about a fundamental change in the status of frontier areas in this region. The paper examines the new transborder relationships as well as the conditions, forms and dynamics of integration processes on the example of Poland. It discusses some stimuli and barriers to cross-border co-operation, including the creation of new transborder institutional embeddedness (e.g. Euroregions). On the other hand, the paper stresses the role of the informal economy in the current development of border zones in East-Central Europe. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

用Voronoi图描述空间方向关系的理论依据   总被引：8，自引：3，他引：8  

闫浩文  郭仁忠 《武汉大学学报(信息科学版)》2002,27(3):306-310

基于可视点，可视链，可视区域等概念，分析了影响空间方向判断的两个因子：两目标群凸壳的直径与可视区域，证明了用Voronoi图描述空间方向关系的可行性。  相似文献   

空间方向关系基础性问题研究   总被引：10，自引：1，他引：10  

闫浩文  郭仁忠 《测绘学报》2002,31(4):357-360

空间方向关系是GIS的重要理论问题，但目前关于它的研究尚处于很不系统的阶段。相关文献大部分专注于空间方向关系的形式化描述模型研究，而忽视了对概念等基础性理论的剖析，本文阐述了研究空间方向关系的意义，空间方向关系的参考框架、性质、特点及分类体系等重要问题，以促进其他相关研究工作的开展。  相似文献   

A sedimentological approach to P-A relationships for tidal inlet systems: an example from Yuehu Inlet, Shandong Peninsula, China     

Jianjun Jia  Shu Gao 《Frontiers of Earth Science》2008,2(3):262-268

Power-law relationship between tidal prism (P) and the cross-sectional area of the entrance channel (A) is applicable to assess the equilibrium conditions of a tidal inlet system. The classic method of determining P-A relationships proposed by O’Brien depends on datasets from multi-tidal inlet systems, which has shown some limitations and is unable to assess equilibrium of a single tidal inlet. This paper focuses on establishing a new P-A relationship for a single tidal inlet. Our experimental result shows that in order to maintain the status, power n should be > 1, implying that the inlet width will narrow and current speed within the entrance will increase as tidal prism becomes smaller. A possible explanation for power n <,1.0, as many researchers argued before, is that the influence of tidal prism has been exaggerated. Meanwhile, the magnitude of coefficient C is dependent on many factors such as longshore drift, freshwater discharge, etc, resulting in a wide range of variation of C. It should be pointed out that P-A relationship given by the sediment dynamical approach is still a representative of average status for tidal inlets in equilibrium. As tide, wave, freshwater discharge and tidal inlet morphology change with time, actual P-A relationships will fluctuate also. The problems that need to be solved when applying sediment dynamic methods to P-A relationships include the cross-sectional distribution pattern of tidal current speeds in the entrance channel, the relationship between the tidal current and the tidal water level at the entrance, and the calculation of the ratio of width to depth. This paper will establish a sediment dynamical approach of P-A relationship for a single tidal inlet. The results are tested for P-A relationships of Yuehu Inlet, a small inlet-lagoon system located in Shandong Peninsula, China. __________ Translated from Oceanologia Et Limnologia Sinica, 2005, 36(3): 269–276 [译自: 海洋与湖沼]  相似文献   

Length-weight relationships for six freshwater fish species in Iran   总被引：2，自引：0，他引：2  

M. S. HEYDARNEJAD 《中国海洋湖沼学报》2009,27(1):61-62

The aim of this study is to report the length-weight relationship parameters (a and b) for some economically important fish species from Iranian freshwaters. The length-weight relationships (LWR) are calculated for six freshwater fish species collected during 2006 and 2007 in Iran. The values of the exponent b in the LWR (W=aLb) vary between 2.985 and 3.543. The LWR with high correlation coefficient (r2) is significant for all the species. These parameters are of great importance to evaluate the relative condition of populations, biology, species management and their fisheries and stock assessment. The application of the length-weight relationships presented here should be limited to the observed length ranges.  相似文献