基于MAPGIS的城镇土地定级估价信息系统设计与实现   总被引：1，自引：0，他引：1  

韩志刚  秦奋  杨建锋  焦学军 《测绘科学》2010,35(5)

针对当前城镇土地定级估价信息系统开发中的不足,提出了基于MAPGIS开发实现城镇土地定级估价信息系统的思路。首先,在综合分析系统需求的基础上,进行了系统的总体设计,选定了开发方式,完成了系统的总体逻辑框架;其次,根据系统的数据内容,结合MAPGIS数据模型,给出了系统数据库设计原则并进行了系统数据库设计;最后,从基础数据组织、参数数据管理、基于A*算法的最短距离计算及地价样点数据探索性空间分析四个方面进行了探讨,提出了相应的解决方案,最终实现了城镇土地定级估价信息系统。  相似文献   

A Comparative Study of Landsat‐7 and Landsat‐8 Data Using Image Processing Methods for Hydrothermal Alteration Mapping          下载免费PDF全文

Feizollah Masoumi  Taymour Eslamkish  Mehdi Honarmand  Ali Akbar Abkar 《Resource Geology》2017,67(1):72-88

Comparing spaceborne satellite images of Landsat‐8 Operational Land Imager (OLI) and Landsat‐7 Enhanced Thematic Mapper plus (ETM+) was undertaken to investigate the relative accuracy of mapping hydrothermal alteration minerals. The study investigated the northern part of Rabor, which contains copper mineralization occurrences, and is located in the Kerman Cenozoic magmatic assemblage (KCMA), Iran. Image processing methods of band ratio, principal component analysis (PCA), and spectral angle mapper (SAM) were used to map the distribution of hydrothermally altered rocks associated with the porphyry copper mineralization. The band ratio combination of both sensors for mapping altered areas showed similar outcomes. PCA exposed variations in the spatial distribution of hydroxyl‐bearing minerals. The representation of hydrothermal areas using OLI data was more satisfactory than when using ETM+ data. SAM analysis found similar results for mapping hydroxyl‐bearing zones. Verification of the results came through ground investigation and laboratory studies. Rock samples (n = 56) were collected to validate results using thin sections, X‐ray diffraction (XRD) and spectral analyses. Field observations and laboratory analysis revealed that phyllic and propylitic alterations dominate the alteration zones in the study area. Argillic and iron oxides/hydroxides alterations were observed to a lesser degree. The results indicate that alteration maps prepared by OLI data using PCA for visual interpretation are more suitable than those of ETM+ due to a higher radiometric resolution and lower interference between vegetation and altered areas. As the spectral bandwidth of ETM+ band 7 covers absorption feature of propylitic alteration, better mapping of propylitic alterations is achieved using ETM+ data.  相似文献   

欧亚地震带地震活动增强与中国大陆地区7级以上地震发生的关系分析     

陈学忠  李艳娥  王恒信 《地震》2014,34(1):34-40

根据欧亚地震带7级以上地震释放能量与全球7级以上地震释放总能量之比,利用χ²检验方法对欧亚地震带地震活动增强与中国大陆地区7级以上地震发生的关系进行了统计检验。结果表明,当出现欧亚带年地震释放能量比高于50%且有8级以上地震发生时,其后3年内中国大陆地区将有发生多次7级以上地震或8级地震的可能性,这个关系在10%的显著水平下通过显著性检验。  相似文献   

唐山7.8级地震前的震中迁移与远台前兆的关系     

郭增建  郭安宁 《华北地震科学》2014,(4):1-3

以震中迁移始发点的前兆讨论了唐山7.8级地震震中位置的预测,并以此为例分析了汶川8级地震和芦山7级地震的前兆问题。另外,从震中迁移延长线上的前兆来讨论了唐山大震的发生时间。  相似文献   

Could CoRoT-7b and Kepler-10b be remnants of evaporated gas or ice giants?     

Leitzinger M  Odert P  Kulikov YN  Lammer H  Wuchterl G  Penz T  Guarcello MG  Micela G  Khodachenko ML  Weingrill J  Hanslmeier A  Biernat HK  Schneider J 《Planetary and Space Science》2011,59(13):1472-1481

We present thermal mass loss calculations over evolutionary time scales for the investigation if the smallest transiting rocky exoplanets CoRoT-7b (∼1.68R_Earth) and Kepler-10b (∼1.416R_Earth) could be remnants of an initially more massive hydrogen-rich gas giant or a hot Neptune-class exoplanet. We apply a thermal mass loss formula which yields results that are comparable to hydrodynamic loss models. Our approach considers the effect of the Roche lobe, realistic heating efficiencies and a radius scaling law derived from observations of hot Jupiters. We study the influence of the mean planetary density on the thermal mass loss by placing hypothetical exoplanets with the characteristics of Jupiter, Saturn, Neptune, and Uranus to the orbital location of CoRoT-7b at 0.017 AU and Kepler-10b at 0.01684 AU and assuming that these planets orbit a K- or G-type host star. Our findings indicate that hydrogen-rich gas giants within the mass domain of Saturn or Jupiter cannot thermally lose such an amount of mass that CoRoT-7b and Kepler-10b would result in a rocky residue. Moreover, our calculations show that the present time mass of both rocky exoplanets can be neither a result of evaporation of a hydrogen envelope of a “Hot Neptune” nor a “Hot Uranus”-class object. Depending on the initial density and mass, these planets most likely were always rocky planets which could lose a thin hydrogen envelope, but not cores of thermally evaporated initially much more massive and larger objects.  相似文献   

2014年2月12日于田7.3级地震序列震源机制特征分析     

李金  王琼 《中国地震研究》2015,29(4):527-538

基于新疆及西藏区域数字地震台网的宽频带资料,采用CAP方法反演了2014年2月12日于田7.3级地震的前震、主震及早期MS≥3.5余震序列的震源机制解。结果显示,此次7.3级强震为带有正断分量的走滑型地震,结合震源区的构造和余震分布,节面I走向241°/倾角90°/滑动角-22°,判定该节面代表了主震的发震断层面。主震主压力轴方位为194o,与该区历史中强震主压应力P轴方位近NS向较为接近。其5.4级前震和主震震源机制解具有较高的一致性。18次余震中有10次为走滑型地震,其中6次为正断型,2次为逆断型,且70%的地震具有近SN向的P轴方位。此次7.3级地震序列震源深度范围5~28km,而大部分地震为15~20km,略大于本文计算得到的主震震源深度10km。  相似文献   

鄂尔多斯盆地西南缘泾河油田长7-长8古流向及 沉积相分析   总被引：1，自引：0，他引：1  

潘杰  刘忠群  蒲仁海  周思宾  范久霄  刘祎楠 《沉积学报》2017,35(1):124-138

对泾河油田三维地震前积反射、钻井取芯砂岩轻重矿物分离测试和砂体剖面结构对比,并结合前人研究结果认为,泾河油田长8-长7砂岩碎屑主要来自于西南部陇西古陆,部分来自于南部秦岭物源,不受北东物源影响。结合物源、岩芯特征和测井相分析结果认为,泾河油田整个长8₁自下而上是河流-三角洲-半深湖的水进沉积过程,发育3条北东向和1条南北向河道。长8₁2为滨浅湖相-三角洲-河流相沉积,发育（水下）分流河道砂岩;长8₁1储层为浅湖-半深湖背景中水进三角洲水下分流河道砂岩。长7₂为浊积砂岩储层,发育9个北东向浊积水道。  相似文献   

TRMM卫星降水反演数据在珠江流域的适用性研究——以东江和北江为例          下载免费PDF全文

王兆礼  钟睿达  赖成光  陈晓宏  李军  黄泽勤 《水科学进展》2017,28(2):174-182

为评估最新一代TRMM 3B42-V7卫星降水反演数据产品在珠江流域的精度和适用性,选取位于珠江流域下游的东江和北江流域为研究区域,基于地面雨量站点数据评估了该产品的精度和适用性,并结合可变下渗容量（Variable Infiltration Capacity,VIC）水文模型进行了水文模拟验证。对比分析结果表明,在网格尺度上,大多数网格日尺度相关系数达到0.60以上,月尺度相关系数达到0.90以上,3B42-V7产品表现出较好的精度,在区域尺度上精度得到了进一步提高;水文模拟验证分两种情景下进行,情景Ⅰ的结果表明,当水文模型由地面雨量站点数据率定时,3B42-V7产品数据的水文模拟效果不佳,个别区间内存在对洪峰流量明显的低估;情景Ⅱ的结果表明,由3B42-V7产品数据重新率定水文模型时径流模拟效果有了较大改善,说明该产品可在一定程度上作为资料缺乏地区的降水数据来源。  相似文献   

Silicate‐oxide mineral chemistry of mafic–ultramafic rocks as an indicator of the roots of an island arc: The Chilas Complex,Kohistan (Pakistan)          下载免费PDF全文

Rubina Bilqees  M. Qasim Jan  M. Asif Khan  Brian F. Windley 《Island Arc》2016,25(1):4-27

The Chilas Complex is a major lower crustal component of the Cretaceous Kohistan island arc and one of the largest exposed slices of arc magma chamber in the world. Covering more than 8000 km², it reaches a current tectonic width of around 40 km. It was emplaced at 85 Ma during rifting of the arc soon after the collision of the arc with the Karakoram plate. Over 85% of the Complex comprises homogeneous, olivine‐free gabbronorite and subordinate orthopyroxene–quartz diorite association (MGNA), which contains bodies of up to 30 km² of ultramafic–mafic–anorthositic association (UMAA) rocks. Primary cumulate textures, igneous layering, and sedimentary structures are well preserved in layered parts of the UMAA in spite of pervasive granulite facies metamorphism. Mineral analyses show that the UMAA is characterized by more magnesian and more aluminous pyroxene and more calcic plagioclase than those in the MGNA. High modal abundances of orthopyroxene, magnetite and ilmenite (in MGNA), general Mg–Fe–Al spatial variations, and an MFA plot of whole‐rock analyses suggest a calc‐alkaline origin for the Complex. Projection of the pyroxene compositions on the Wo–En–Fs face is akin to those of pyroxenes from island arcs gabbros. The presence of highly calcic plagioclase and hornblende in UMAA is indicative of hydrous parental arc magma. The complex may be a product of two‐stage partial melting of a rising mantle diaper. The MGNA rocks represent the earlier phase melting, whereas the UMAA magma resulted from the melting of the same source depleted by the extraction of the earlier melt phase. Some of the massive peridotites in the UMAA may either be cumulates or represent metasomatized and remobilized upper mantle. The Chilas Complex shows similarities with many other (supra)subduction‐related mafic–ultramafic complexes worldwide.  相似文献   

The Godzilla Megamullion,the largest oceanic core complex on the earth: a historical review   总被引：1，自引：0，他引：1       下载免费PDF全文

Yasuhiko Ohara 《Island Arc》2016,25(3):193-208

The Godzilla Megamullion is the largest known oceanic core complex (OCC) on the Earth, located in the Parece Vela Basin in the Philippine Sea. In this article, the history of Godzilla Megamullion study is reviewed for the first time, dividing it into three major phases: (i) the early studies done before Japan's extended continental shelf survey program; (ii) the studies during Japan's extended continental shelf survey program that discovered the OCC; and (iii) the studies by the post‐discovery cruises. The early studies included an interpretation of US nautical chart of the southwestern Pacific and the site surveys for Deep Sea Drilling Project cruises (DSDP Legs 6, 31 and 59). The early studies recognized the presence of the Parece Vela Rift, the extinct spreading axis of the Parece Vela Basin, and established the currently accepted model that the Philippine Sea evolved with eastward progression of backarc spreading and arc migration. The modern understanding of the Parece Vela Basin comes from Japan's extended continental shelf survey program. The program revealed the ultramafic petrology as well as a two‐stage evolution model of the basin. Following these results, the discovery of the Godzilla Megamullion was made in 2001. The studies by the post‐discovery cruises further revealed important characteristics of the OCC, such as the presence of abundant plagioclase‐bearing peridotite and the systematic temporal changes in both deformation microstructures and composition of plagioclase and amphibole in gabbroic mylonites and ultramylonites. Zircon U–Pb ages of gabboric and leucocratic rocks indicate that the terminal phase of Parece Vela Basin spreading was with a significant decline in spreading rate and asymmetry accompanying formation of the Godzilla Megamullion. The estimated denudation rate of the OCC was approximately 2.5 cm/yr; significantly slower than the previous estimate based on poorly constrained magnetic data.  相似文献