城市热岛效应监测方法研究进展   总被引：16，自引：0，他引：16  

肖荣波  欧阳志云  张兆明  王效科  李伟峰  郑华 《气象》2005,31(11):3-6

城市热岛效应是一种由于城市建筑及人们活动导致的热量在城区空间范围内聚集的现象,是城市气候最明显的特征之一.由于城市热岛影响因素以及相互关系的复杂性,为了精确细致地描述其时空分布,人们采用了多种方法来研究城市热岛现象,主要归纳为：气象站法、定点观测法、运动样带法、遥感测定法以及模拟预测等.最后,认为各种测定方法都存在一定的缺陷,建议多种测定方法综合运用.  相似文献   

岩石水压致裂和诱发地震的实验研究   总被引：5，自引：0，他引：5  

颜玉定  李亚林  张专  欧阳立胜  谢明富 《中国地震》2005,21(2):193-206

用7种岩石各制备了几类不同预裂纹的系列试件，并在不同围压下进行水压致裂强度实验。结合典型的水库诱发地震的实际资料和现今构造应力场的实验结果，以及应用岩石强度理论和岩石断裂力学的一些原理、方法，进行岩石孔隙水压诱发地震的探讨。初步结果为：(1)若岩体内构造应力很小，一定大小的孔隙水压力σp，可直接使岩体内的薄弱面致裂并发生小地震。(2)若构造应力较大，存在两类诱发地震的可能：①对岩体浅部一些走向与构造应力的主压应力σ1方向相近的薄弱面，σp可促使其发生张性破裂并诱发小地震。②当构造应力接近于断裂的抗剪强度时，因σp，降低了断裂面上的正应力σn，使原处于稳定状态的断裂失稳，发生滑移破裂并诱发出地震。σp导致断裂的破裂深度增大，使诱发地震的震级大于原潜在的地震震级。(3)各种岩体均存在着一个极限深度，此深度后不再有诱发地震。  相似文献   

A preliminary study on mineralogical and chemical compositions of some chondrites falling in China     

Daode Wang  Ziyuan Ouyang  Wei Hou 《中国地球化学学报》1982,1(2):186-199

Samples are available from 37 stony meteorites falling in China. Twenty-two chondrites are examined in terms of chemical and mineral compositions, cosmogenic nuclides, formation and exposure ages, impact effect and chondrule textures. On the basis of chemical-petrologic features these chondrites are classified asE ₄ (Qingzhen),H ₅ (Jilin, Changde, Shuangyang, Anlong, Xinyi and Yangjang),L ₆ (Renqiu, Junan, Heze, Rugao and Nei Monggol) andLL ₆ (Dongtai). E ₄ is characterized by high iron and sulfur, with the former occurring mainly as Fe^o and FeS. FromH ₅ throughH ₆ toLL ₆, iron and nickel decrease gradually while FeO and the ratio of Fe silicate to total iron increase gradually. indicating a general increase in the orderE-H-L-LL in the degree of oxidation at the time of formation. E ₄ consists mainly of enstatite and, to much less extent, free SiO₂ but olivine is hardly to be found. The olivine proportions amount to 29.07, 41.98 and 51.36 percent inH ₅,L ₆ andLL ₆ respectively, with Fa increasing from 17 to 27 percent. Recrystallization has been noticed to different degrees inH ₄,H ₅,L ₆ andLL ₆ chondrites. The extent to which the original structure disappears and the boundaries of chondrules become indistinct decreases from type 6 through type 5 to type 4, reflecting different degrees of thermal metamorphism. Major minerals in the meteorites all exhibit signs of low to medium shock metamorphism. Specific activity, depth effect and orbit effect are also measured on some chondrites that have fallen in recent years and some new information has been obtained with respect to the orbit and source region for meteorite parent bodies in space. This results show that the environment of formation ofE group may be nearer to Mars than that ofO group. Each chemical group of chondrites has its own evolutionary history, and chondritets of different chemical groups may have originated from parent bodies of different compositions. Or owing to the differentiation caused by thermal melamorphism, various kinds of meteorites may be derived from a common parent body. From this argument it is suggested that five stages may be recognized during the formation process of chondrites.  相似文献   

断层封闭性研究进展   总被引：40，自引：0，他引：40  

鲁兵  刘忠 《地质科技情报》1998,17(3):75-80

对断层封闭性的研究现状进行了总结,概述了断层封闭性理论机理,影响因素和评价方法,对其中存在的一些问题如封闭机理及与有关的评价方法,构造反转与断层封闭的关系以及断层封闭性的三维研究问题进行了讨论。  相似文献   

空间直角坐标和大地坐标的转换   总被引：5，自引：0，他引：5  

黄谟涛  翟国君  管铮  欧阳永忠 《测绘学院学报》1998,(3)

目前国内在空间直角坐标和大地坐标转换公式使用问题上 ,还明显缺乏必要的统一性。针对这个问题 ,本文作者在全面分析和比较国内外现有各种转换方法的基础上 ,重点推荐和介绍根据 Bowring研究思路导出的转换公式 ,这组公式既简单又具有很高的计算精度 ,能够满足各个部门的使用要求  相似文献   

用T/P测高数据反演海域重力异常     

欧阳永忠  翟国君 《测绘学院学报》1998,(1)

以反解 Stokes公式为数学模型 ,应用由 T/ P测高数据计算的大地水准面高反演了海域平均重力异常 ,并与船测平均重力异常和 OSU91A位模型计算的平均重力异常进行了比对分析 ,得出了一些有益的结论。  相似文献   

Preliminary study on weathering and pedogenesis of carbonate rock   总被引：23，自引：0，他引：23  

Shijie Wang  Hongbing Ji  Ziyuan Ouyang  Dequan Zhou  Leping Zhen  Tingyu Li 《中国科学D辑(英文版)》1999,42(6):572-581

South China is the largest continuous distribution area of carbonate rock in the world. The origin of the soils over the bedrock carbonate rock has long been a controversial topic. Here further exploration is made by taking five soil profiles as examples, which are developed over the bedrock dolomitite and limestone and morphologically located in upland in karst terrain in the central, west and north Guizhou as well as west Hunan, and proved to be the weathering profiles of carbonate rock by the research results of acid-dissolved extraction experiment of bedrock, mineralogy and trace element geochemistry. Field, mineralogical and trace element geochemical characteristics of weathering and pedogenesis for carbonate rock are discussed in detail. It is pointed out that weathering and pedogenesis of carbonate rock are important pedogenetic mechanisms for soil resources in karst area, providing a basis for further researches on the origin of soils widely overlying bedrock carbonate rocks in South China. Project supported by the National Natural Science Foundation of China (Grant No. 498330003) and National Key Basic Research Project (Grant No. 95pre-39).  相似文献   

测高数据在计算海平面时的取权     

翟国君  欧阳永忠  黄谟涛  王瑞 《武汉大学学报(信息科学版)》1999,(2)

根据卫星测高数据分布所具有的低纬时稀疏、高纬时密集的特点,提出了计算平均海平面时非交叉点数据的解析定权公式和交叉点数据的解析定权公式。  相似文献   

A Preliminary Study on Dust Grains in the Stratosphere     

黄伯钧  欧阳自远 《中国地球化学学报》1990,9(2):105-114

Collected by means of a high-altitude scientific balloon and a self-made automatic sample collector,a total of 276 dust grains were selected for the study of shape,grain size and optical property.Some of the grains were examined by X-ray diffraction and electrom microprobe techniques,The stratospheric dust grains can be classified as 6 types:cosmic dusts,cosmic dusts(?),microtektite,natural pollutants,artificial pollutants and the unknown substances.The different types of dust grains have different characters and distinguishing symbols.Widespread in the space of the solar system,cosmic dusts are the initial substances of the solar system and ,to some degree,have recorded a great wealth of information on the early history of the solar system.So they have become one of the important objects in the field of cosmochemistry at present time,Since the 1960‘s,scholars of many countries have collected cosmic dusts both in the space near the earth(using rock ets,space probes and space shuttles)and in the stratosphere (using high-altitude balloons or U-2air planes).According to the shape(the scanning electron microimage),element composition(the energy-dispersive X-ray spectrum)and optical properties of dust grains,the substances in the stratosphere can be classified as 5 types:cosmic dusts,alumina spheroids,terrestrial artificial pollutants,terrestrial natural pollutants and unknown substances(CDPET,1982).  相似文献   

海洋平均重力异常计算与精度估计     

黄谟涛  管铮  欧阳永忠 《武汉大学学报(信息科学版)》1995,(4)

提出了一种简便实用的重力异常推值方法──方位距离加权中数法，给出了直接使用重力异常变化梯度作为衡量平均重力异常计算精度的尺度，并运用ＯＳＵ９１Ａ模型成功地建立起重力异常变化梯度与平均重力异常计算精度的相关关系，通过此关系可对海洋平均重力异常计算精度作出比较可靠的估计。  相似文献