2010年智利Ms8．8地震震相特征分析     

陈翔  邓存华  余庆坤  李雷  黄瑶 《地震地磁观测与研究》2012,33(5):35-39

对昆明地震台数字地震仪记录的2010年2月27日智利Ms8．8地震的震相进行分析,与格尔木、高台、呼和浩特、成都、银川、兰州、西妥等7个地震台记录进行对比,提出智利地震的记录特征、分析难点,并将JB表中Pdif波走时曲线的截止距离从150°延伸到177．8°。  相似文献   

广州开发区的发展演变与空间效应研究   总被引：1，自引：0，他引：1  

王峰玉  赵淑玲 《云南地理环境研究》2008,20(3):76-83

以广州开发区为研究对象,依据产业规模、发展速度和空间拓展等方面的因素,认为经过20多年的发展,其经历了起步发展、快速扩张、综合优化3个阶段的演变过程。开发区在自身经济实力增强和空间规模壮大的同时,产生了巨大的空间效应,使广州城市空间拓展方式从“连片式”向“跳跃式”转变,引导城市不断向东拓展;形成经济增长极,提升东部板块,改变了广州的地域空间结构,形成了新的功能格局。  相似文献   

地球深部金属碳化物的晶体化学   总被引：4，自引：0，他引：4  

施倪承  白文吉  李国武  方青松  马喆生  杨经绥  熊明  颜秉刚 《地学前缘》2005,12(1):29-36

金属碳化物的矿物十分稀少,但人工合成物则在化学成分及晶体结构两方面分布均较为丰富,可分成两种结构类型,即填隙结构型及复杂化合物型,其形成机理与碳原子与金属原子的半径比(Rc/Rm)有关。金属碳化物是西藏罗布莎铬铁矿床地幔矿物群的重要组成部分。列举了在该地区已发现的若干金属碳化物种属。探讨了该类矿物的形成机理以及该类矿物中的某些种属表征其形成的温度、压力状态的可能性。  相似文献   

Reactive-transport modeling of fly ash–water–brines interactions from laboratory-scale column studies     

《Physics and Chemistry of the Earth》2014

Dynamic leaching tests are important studies that provide more insights into time-dependent leaching mechanisms of any given solid waste. Hydrogeochemical modeling using PHREEQC was applied for column modeling of two ash recipes and brines generated from South African coal utility plants, Sasol and Eskom. The modeling results were part of a larger ash–brine study aimed at acquiring knowledge on (i) quantification and characterization of the products formed when ash is in contact with water–brines in different scenarios, (ii) the mineralogical changes associated with water–brine–ash interactions over time, (iii) species concentration, and (iv) leaching and transport controlling factors. The column modeling was successfully identified and quantified as important reactive mineralogical phases controlling major, minor and trace elements’ release. The pH of the solution was found to be a very important controlling factor in leaching chemistry. The highest mineralogical transformation took place in the first 10 days of ash contact with either water or brines, and within 0.1 m from the column inflow. Many of the major and trace elements Ca, Mg, Na, K, Sr, S(VI), Fe, are leached easily into water systems and their concentration fronts were high at the beginning (within 0.1 m from the column inflow and within the first 10 days) upon contact with the liquid phase. However, their concentration decreased with time until a steady state was reached. Modeling results also revealed that geochemical reactions taking place during ash–water–brine interactions does affect the porosity of the ash, whereas the leaching processes lead to increased porosity. Besides supporting experimental data, modeling results gave predictive insights on leaching of elements which may directly impact on the environment, particularly ground water. These predictions will help develop scenarios and offer potential guide for future sustainable waste management practices as a way of addressing the co-disposal of brines within inland ash dams and heaps.  相似文献   

郑州城市发展历程与特点分析   总被引：5，自引：1，他引：4  

王旭升  董桂萍  毛卉 《地域研究与开发》2005,24(6):47-51

采取实证分析研究方法,考察郑州城市历史发展演变过程,总结不同发展阶段特点,探寻影响城市发展的基本因素及规律,为制定城市发展策略提供依据,认为交通枢纽、省会地位、工业项目建设布局和国家宏观政策与环境,是影响郑州城市建设与发展的4个重要动力因素,并将长期发挥作用。  相似文献   

Sedimentogenesis cyclicity, stages, and phases in the development of the Late Silurian-Early Devonian biota in Northeast Asia     

V. V. Baranov 《Stratigraphy and Geological Correlation》2009,17(4):382-395

It is established that the Pridolian-Eifelian megacycle in Northeast Asia is represented by five macrocyclites. The analysis of fossils in Upper Silurian-Lower Devonian sections of the region reveals ten levels marked by large-scale reorganizations in the composition and structure of the biota in this basin. These levels are united in pairs by five maximums, which are characterized by the highest values of the taxonomic renewal coefficient, coincide with the boundaries of macrocyclites, and are traceable through the entire sedimentation basin.  相似文献   

瑞雷波"之"形速度-深度曲线的成因   总被引：11，自引：5，他引：6  

陈祥  孙进忠  刘景儒 《地球物理学进展》2004,19(4):860-863

本文通过对层状介质的瑞雷方程进行求解,验证了层状介质中瑞雷波的多阶性,讨论了各阶导波对频散曲线的影响．在此基础上,从两个方面对实测速度-深度曲线常出现的“之”字形进行了解释,提出了其中还有待进一步解决的问题及相应的建议．  相似文献   

流动站与参考站不同采样率GPS数据的处理策略     

王海涛  欧吉坤  袁运斌  柴艳菊 《武汉大学学报(信息科学版)》2010,(2)

针对GPS流动站与参考站采用不同采样率的特殊应用情况,当观测数据不同步时,采用历元间的相位差分计算流动站的高精度"伪距",进而单独进行导航定位解算;当流动站与参考站观测数据同步时,采用双差模式。该方案不但充分利用了观测数据,而且可以节省数据采集和传输及运算的成本。飞机导航试验的数据解算表明,采用这种方法,流动站的定位精度可以达到cm级,而且位置更新率较高。  相似文献   

鄂西清江流域中新生代区域构造应力场研究   总被引：6，自引：0，他引：6  

吴树仁  陈庆宣  梅应堂  徐瑞春  石玲  刘子忠 《地球学报》1995,16(2):135-151

本文在简要分析清江流域区域构造格架及其演化序列的基础上，将清江流域中新生代区域构造应力场划分为：燕山主期、喜马拉雅主期和现今构造应力场。进而利用共轭节理、断层擦痕、显微构造分析、震源机制解和地应力测量资料等定量反演各期构造应力场的主应力方法；同时利用岩石破坏准则、方解石鹅e双晶和变形矿物的位错密度等定量估算其差异应力。并结合有限元模拟计算，探讨清江流域中新生代区域构造应力场的基本特征及其演化规律，为区域地壳稳定性评价提供重要依据。  相似文献   

云南个旧锡矿的成矿时代   总被引：23，自引：0，他引：23       下载免费PDF全文

秦德先  黎应书  谈树成  陈爱兵  薛传东  范柱国  党玉涛  童祥  武俊德  李玉新  王海云 《地质科学》2006,41(1):122-132

云南个旧锡矿经历了印支期海底基性火山——沉积成矿、海底喷流——沉积成矿和燕山晚期的花岗岩叠加改造成矿的作用。用Ar-Ar、K-Ar和Pb-Pb法分析了3个成矿系列的成矿年龄,结果表明,成矿系列Ⅰ的Ar-Ar法坪年龄和等时线年龄为95.93±5.41～123.91±15.41Ma,K-Ar法表观年龄为112.50±2.25Ma,普通铅法年龄为210～240Ma;成矿系列Ⅱ的Ar-Ar法坪年龄和等时线年龄为191.81±2.26～205.11±4.38Ma,K-Ar法表观年龄为186.01±3.72Ma,普通铅法年龄为200～230Ma;成矿系列Ⅲ的Ar-Ar法坪年龄和等时线年龄为83.23±2.07～85.22±2.38Ma,K-Ar法表观年龄为43.49±0.87Ma,普通铅法年龄为83～116Ma。  相似文献