基于MAPGIS7.0的大规模E00数据转换的研究与实现     

周顺平  丛琳  杨林  万波 《测绘科学》2009,34(6)

针对大型E00数据文件转换问题,本文在常规的数据格式转换模式基础上,结合MapGIS7.0"要素—几何—空间"的三层数据组织模型,研究了E00数据组织与MapGIS7.0数据组织的映射关系,设计了基于Map-GIS7.0平台的大型E00数据格式转换的方法。使大规模E00数据转换的效率大大提高。该数据转换工具已经应用于MapGIS7.0软件,能够满足E00数据与MapGIS7.0数据格式转换的应用需求。  相似文献   

微波辐射计探测降雨前水汽和云液水   总被引：9，自引：2，他引：9       下载免费PDF全文

雷恒池  魏重  沈志来  梁谷  李燕 《应用气象学报》2001,12(Z1):73-79

1997年8～11月在陕西西安使用双通道地基微波辐射计对降水云系进行探测，除得到云中水汽含量(Q)和垂直路径积分云液水含量(L)的一般统计特征量外，还发现在降雨开始前，Q和L的数值均有跃增现象。提出在降水云系前方（周围）存在丰水区的假设，这里可能是云滴向雨滴转化的孕育区、人工增雨最佳作业区。  相似文献   

Petrology of ultrahigh-pressure rocks from the southern Su-Lu region, eastern China   总被引：44，自引：2，他引：44  

RU-YUAN ZHANG  T. HIRAJIMA  S. BANNO  BOLIN CONG  J. G. LIOU 《Journal of Metamorphic Geology》1995,13(6):659-675

Abstract In the Su-Lu ultrahigh- P terrane, eastern China, many coesite-bearing eclogite pods and layers within biotite gneiss occur together with interlayered metasediments now represented by garnet-quartz-jadeite rock and kyanite quartzite. In addition to garnet + omphacite + rutile + coesite, other peak-stage minerals in some eclogites include kyanite, phengite, epidote, zoisite, talc, nyböite and high-Al titanite. The garnet-quartz-jadeite rock and kyanite quartzite contain jadeite + quartz + garnet + rutile ± zoisite ± apatite and quartz + kyanite + garnet + epidote + phengite + rutile ± omphacite assemblages, respectively. Coesite and quartz pseudomorphs after coesite occur as inclusions in garnet, omphacite, jadeite, kyanite and epidote from both eclogites and metasediments. Study of major elements indicates that the protolith of the garnet-quartz jadeite rock and the kyanite quartzite was supracrustal sediments. Most eclogites have basaltic composition; some have experienced variable 'crustal'contamination or metasomatism, and others may have had a basaltic tuff or pyroclastic rock protolith.
The Su-Lu ultrahigh- P rocks have been subjected to multi-stage recrystallization and exhibit a clockwise P-T path. Inclusion assemblages within garnet record a pre-eclogite epidote amphibolite facies metamorphic event. Ultrahigh- P peak metamorphism took place at 700–890° C and P >28 kbar at c . 210–230 Ma. The symplectitic assemblage plagioclase + hornblende ± epidote ± biotite + titanite implies amphibolite facies retrogressive metamorphism during exhumation at c . 180–200 Ma. Metasedimentary and metamafic lithologies have similar P-T paths. Several lines of evidence indicate that the supracrustal rocks were subducted to mantle depths and experienced in-situ ultrahigh- P metamorphism during the Triassic collision between the Sino-Korean and Yangtze cratons.  相似文献   

Petrogenesis of garnet-bearing ultramafic rocks and associated eclogites in the Su-Lu ultrahigh-P metamorphic terrane, eastern China   总被引：10，自引：3，他引：10  

R. Y. ZHANG  J. G. LIOU  BOLIN. CONG 《Journal of Metamorphic Geology》1994,12(2):169-186

Ultramafic blocks that themselves contain eclogite lenses in the Triassic Su-Lu ultrahigh-P terrane of eastern China range in size from hundreds of metres to kilometres. The ultramafic blocks are enclosed in quartzofeldspathic gneiss of early Proterozoic age. Ultramafic rocks include garnetiferous lherzolite, wehrlite, pyroxenite, and hornblende peridotite. Garnet lherzolites are relatively depleted in Al₂O₃ (<3.8wt%), CaO (<3.2%) and TiO₂ (<0.11 wt%), and are low in total REE contents (several p.p.m.), suggesting that the rocks are residual mantle material that was subjected to low degrees of partial melting. The eclogite lenses or layers within the ultramafic rocks are characterized by higher MgO and CaO, lower Al₂O₃ and TiO₂ contents, and a higher CaO/Al₂O₃ ratio compared to eclogites enclosed in the quartzofeldspathic gneiss. Scatter in the plots of major and trace elements vs. MgO, REE patterns and La, Sm and Lu contents suggest that some eclogites were derived from melts formed by various degrees (0.05–0.20) of partial melting of peridotite, and that other eclogites formed by accumulation of garnet and clinopyroxene ± trapped melt in the upper mantle. Both ultramafic and eclogitic rocks have experienced a complex metamorphic history. At least six stages of recrystallization occurred in the ultramafic rocks based on an analysis of reaction textures and mineral compositions. Stage I is a high temperature protolith assemblage of Ol + Opx + Cpx + Spl. Stage II consists of the ultrahigh-pressure assemblage Ol + Cpx + Opx + Grt. Stage III is manifested by the appearance of fine-grained garnet after coarse-grained garnet. Stage IV is characterized by formation of kelyphitic rims of fibrous Opx and Cpx around garnet, and replacement of garnet by spinel and pargasitic-hornblende. Stage V is represented by the assemblage Ol + Opx + Prg-Hbl + Spl. The mineral assemblages of stages VI_A and VI_B are Ol + Tr-Amp + Chl and Serp + Chl ± talc, respectively. Garnet and orthopyroxene all show a decrease in MgO with retrogressive recrystallization and Na₂O in clinopyroxene also decreases throughout this history. Eclogites enclosed within ultramafic blocks consist of Grt + Omp + Rt ± Qtz ± Phn. A few quartz-bearing eclogites contain rounded and oval inclusion of polycrystalline quartz aggregates after coesite in garnet and omphacite. Minor retrograde features include thin symplectic rims or secondary amphiboles after Cpx, and ilmenite after rutile. P-T estimates indicate that the ultrahigh-metamorphism (stage II) of ultramafic rocks occurred at 820-900d? C and 36-41 kbar and that peak metamorphism of eclogites occurred at 730-900d? C and >28 kbar. Consonant with earlier plate tectonic models, we suggest that these rocks were underplated at the base of the continental crust. The rocks then underwent ultrahigh-pressure metamorphism and were tectonically emplaced into thickened continental crust during the Triassic collision between the Sino-Korean and Yangtze cratons.  相似文献   

黄河封河期冰凌预警地电测试技术研究   总被引：3，自引：0，他引：3       下载免费PDF全文

丛沛桐  王瑞兰  李翠霞 《水科学进展》2006,17(6):877-880

黄河流域地形地貌相差悬殊,受西伯利亚和蒙古一带冷空气的影响,冬春季干、支流有不同程度的冰情出现.由于黄河凌情来势迅猛,水位急剧壅高,易决口成灾,开展冰凌预警研究是十分必要的.黄河封河期冰盖下流凌量及冰塞体的生长状况是黄河冰凌预警的关键要素,采用地电测试技术,对冰水两相流进行视电阻率测量,绘制电测深曲线,数字化模拟冰凌参数,评估冰塞体的生长及冰块堆积状况,为防凌减灾提供预警服务.测试结果表明,平稳流凌时,测深曲线经子波分解后阈值为10Ω·m左右,当出现局部冰塞时阈值达到100Ω·m左右,数值易于区分,基于电测深曲线的差异性进行冰凌预警的方法是可行的,可为防凌减灾提供预警服务.  相似文献   

在我国发现的Schwertmannite矿物及其特征   总被引：5，自引：1，他引：5  

孙红福  赵峰华  丛志远  岳梅  任德贻 《矿物学报》2006,26(1):38-42

采用X射线衍射(XRD)、扫描电镜与能谱(SEM-EDX)、X射线荧光(XRF)、傅立叶红外光谱(FT-IR)、热分析(DTA-TG)等分析方法,在我国山西马兰煤矿的酸性矿坑排水(AMD)沉淀物中首次发现了“斯沃特曼铁矿”(Schwertmannite)。研究表明,山西马兰煤矿酸性矿坑排水沉淀物中的Schwertmannite矿物的粒径为0.3~70μm,且分布比较均匀,其BET表面积为44.065 0 m2/g;SEM二次电子像显示为球形或椭圆形(聚集体)结构,颗粒大小比较均匀,球的表面有针状毛刺;该矿物的化学式为Fe8O8(OH)4.52(SO4)1.74.4.73H2O。  相似文献   

基于GIS组件技术的地下水资源管理信息系统的研究与开发   总被引：7，自引：0，他引：7  

丛方杰  王国利  肖传成  刘锦锋 《水文》2006,26(4):60-63

分析设计了系统的逻辑结构与功能模块的划分,研究了组件式GIS系统开发模式的相关技术,开发了基于GIS组件技术的地下水资源管理信息系统。采用MapObject 2．0与PowerBuilder 8．0相结合的集成开发方式,应用面向对象技术,实现了GIS的地理信息与地下水资源业务管理的信息处理模块的无缝高效集成。用户不需投资购买专门的GIS开发与应用平台,不需学习和掌握专门的GIS开发语言。  相似文献   

辽宁鞍山市岫岩县泥石流区域危险性评价     

王晓朋  潘懋  丛威青  徐岳仁 《水文地质工程地质》2006,33(2):93-95

本文以岫岩县作为研究区域，以自然流域作为评价单元格，采用人工神经网络对该区泥石流的区域危险性进行评价。结果显示，三级以上危险区囊括了99％的泥石流灾害点，评价结果符合实际情况。以流域作为评价单元充分体现了泥石流发生的空间特征和物理机制，危险性区划图直观明了。可为防灾减灾规划提供科学依据。  相似文献   

突发气象灾害预警信号发布管理系统     

丛美环  周淑玲  李强 《山东气象》2006,26(3):21-23

突发气象灾害预警信号发布管理系统采用基于ASP动态网页编程和SQL SERVER数据库技术相结合,用网页形式实现了预警信号数据库的后台管理、信号发布和结果查询。介绍了系统的设计思路、数据结构和主要功能。  相似文献   

新一代多普勒天气雷达在强对流天气过程中的应用     

丛英  张开  杨红 《贵州气象》2006,30(Z1):5-7

介绍多普勒天气雷达产品在2005年4月22-23日强对流天气过程中应用的情况,并对使用多普勒天气雷达产品的过程加以总结,为预报员使用雷达产品预测灾害性天气提供参考。  相似文献