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981.
注入/压降试井作为获取煤储层参数的一个重要手段,近年来获得了广泛的应用.但由于施工设计不合理、现场操作不规范、模型选择不正确等问题,导致测试过程异常和测试结果失真,针对这些问题提出了几种判识方法:利用储层压力值与末点压力值的关系来检验测试结果是否可靠;利用井储系数计算值与实测值的关系及双对数曲线上出现的异常点来检验封隔器是否密封及井下关井是否成功.为了提高注入/压降试井测试过程和结果的可靠性,建议采用推荐的检验方法对试井资料及解释结果进行分析判断,以便合理指导后续勘探开发工作. 相似文献
982.
Carius管溶样-负离子热表面电离质谱准确测定辉钼矿铼-锇同位素地质年龄 总被引:175,自引:30,他引:175
将样品、混合稀释剂和逆王水加入到Carius管中,于230℃溶样10h.利用蒸馏法分离Os,萃取和阴离子交换法分离Re.采用负离子热表面电离质谱精确测定了所研制的年龄标准参考物辉钼矿(HLP)的Re-Os年龄.对取自12个小瓶中17个样品所测平均年龄为221.3±0.3Ma,置信度95%.中值年龄和平均绝对偏差为221.34±0.12Ma.美国克罗拉多州立大学AIRIE小组19次单独取样所测HLP的平均年龄为221.3±1.0Ma,置信度95%.中值年龄和平均绝对偏差为221.34±0.24Ma. 相似文献
983.
Zi-Ling Lü Zheng Zhuang Zhu-Wu Fu Jia-Fu Hu Zhong-He Song Guo-Ying Chen Chang-Qiang An Li-Hua Chen 《地震科学(英文版)》1994,7(1):105-115
The average swelling height of Qinghai-Xizang Plateau (Tibet) is about 4.1 km. The area is about 2 300 000 km2. It is the highest and the largest plateau in the world. Mount Qomolangma, the highest peak in the world, is located in the southern fringe of the plateau, and its height is still increasing. What is the driving force for the rising of the Qinghai-Xizang plateau? How high will the plateau still rise from now on? These questions are much concerned by people. In this paper the distribution of the pressure at different depths in the region of Qinghai-Xizang Plateau are derived according to the three-dimensional structures of the S-wave velocity in the crust and upper mantle. The crust and upper mantle structures of the Qinghai-Xizang Plateau is deliberated on the basis of the distribution with a comprehensive analysis on the rock types, earthquakes and the relative crust movements. Then the two questions raised above are discussed. 相似文献
984.
为了解决征地拆迁数据处理过程中数据量大、统计复杂、容易出错、查询困难等问题,基于VB-NET成功研制了征地拆迁数据处理软件。它的研制成功将提高工作效率,使征地拆迁工作走向科学化、规范化管理。本文介绍了LANDMS软件的结构、组成、功能、测试及特点。 相似文献
985.
<正>1研究目的(Objective)中扬子中部黄陵隆起东南缘宜昌斜坡带在太古宙结晶基底之上,发育有元古宙至第四纪各时代地层,保存有埃迪卡拉系陡山沱组、寒武系水井沱组,奥陶系五峰组—志留系龙马溪组等多套黑色富有机质泥岩。区域构造稳定,地层产状平缓,页岩气地质条件优越,但页岩气的勘探一直未获突破。本文的目的旨在查明宜昌斜坡带寒武系水井沱组页岩的分布和含气性,确定页岩气储层特点,为区域页岩气的勘探开发提供基础资料。 相似文献
986.
Mining Trajectory Data and Geotagged Data in Social Media for Road Map Inference 总被引:1,自引:0,他引:1 下载免费PDF全文
As mapping is costly and labor‐intensive work, government mapping agencies are less and less willing to absorb these costs. In order to reduce the updating cycle and cost, researchers have started to use user generated content (UGC) for updating road maps; however, the existing methods either rely heavily on manual labor or cannot extract enough information for road maps. In view of the above problems, this article proposes a UGC‐based automatic road map inference method. In this method, data mining techniques and natural language processing tools are applied to trajectory data and geotagged data in social media to extract not only spatial information – the location of the road network – but also attribute information – road class and road name – in an effort to create a complete road map. A case study using floating car data, collected by the National Commercial Vehicle Monitoring Platform of China, and geotagged text data from Flickr and Google Maps/Earth, validates the effectiveness of this method in inferring road maps. 相似文献
987.
A total of 11 PM2.5 samples were collected from October 2003 to October 2004 at 8 sampling sites in Beijing city. The PM2.5 concentrations are all above the PM2.5 pollution standard (65 μg m^-3) established by Environmental Protection Agency, USA (USEPA) in 1997 except for the Ming Tombs site. PM2.5 concentrations in winter are much higher than in summer. The 16 Polycyclic aromatic hydrocarbons (PAHs) listed as priority pollutants by USEPA in PM2.5 were completely identified and quantified by high performance liquid chromatography (HPLC) with variable wavelength detector (VWD) and fluorescence detector (FLD) employed. The PM2.5 concentrations indicate that the pollution situation is still serious in Beijing. The sum of 16 PAHs concentrations ranged from 22.17 to 5366 ng m^-3. The concentrations of the heavier molecular weight PAHs have a different pollution trend from the lower PAHs. Seasonal variations were mainly attributed to the difference in coal combustion emission and meteorological conditions. The source apportionment analysis suggests that PAHs from PM2.5 in Beijing city mainly come from coal combustion and vehicle exhaust emission. New measures about restricting coal combustion and vehicle exhaust must be established as soon as possible to improve the air pollution situation in Beijing city. 相似文献
988.
从系统需求分析出发 ,介绍了可视化的长江三峡水库诱发地震预测数据库构建的主要内容及其实施技术路线 ,划分了国内外典型的诱震震例以及长江三峡地区基础地理、诱震地质环境和诱发地震前兆监测等相关基础信息的主要类型 ,确定了各类信息的数据库结构和数据格式。在此基础上 ,对各类基础图形进行数字化处理 ,建立了可视化的图形数据库 ;通过其相关属性信息的录入或转换 ,建立了各类图形相应的属性数据库 ;利用GIS技术 ,对图形数据库及其属性数据库进行了无缝集成 ,实现了图形数据与其相应属性数据间的可视化交互式查询、浏览、管理和分析 相似文献
989.
We process the standard 30 s, static GPS data and the 1 s, high-rate GPS (HRGPS) data provided by the Crustal Movement Observation Network of China with GAMIT/GLOBK software package, and obtain the co-seismic displacements of near field and far field, and the epoch-by-epoch time series of HRGPS during Lushan earthquake. GPS data from about 20 sites in Sichuan province, which located between 40 and 450 km from the epicenter, are analyzed so as to study the characteristics of the static displacements and the dynamic crustal deformations, with periods ranging from several minutes to over a month. The result shows that: the static displacements caused by Lushan earthquake are limited to several centimeters; the nearest station SCTQ at 43 km from the epicenter has the largest static displacement of about 2 cm, while the other stations generally have insignificant displacements of less than 5 mm. the stations in the east of Sichuan–Yunnan region shifts 5–10 mm toward the southwest, and the stations in the middle-west of Sichuan Basin moves indistinctively 1–2 mm toward the northwest; station SCTQ has the largest kinematic displacement of about 4 and 3 cm peak-to-peak on the north and east component, respectively, and is much greater than the static permanent displacement; for the stations located at a distance greater than 150 km from the epicenter, the kinematic motions are generally insignificant; exceptionally, station SCNC and station SCSN in central Sichuan Basin have significant kinematic motions although they are more than 200 km away from the epicenter. 相似文献
990.
Wei-Hua Wang Xiao-Yu Hong Tao AnShanghai Astronomical Observatory Chinese Academy of Sciences Shanghai National Astronomical Observatories Chinese Academy of Sciences Beijing 《中国天文和天体物理学报》2003,3(6):505-512
We present the results of VLBI observations at 5 GHz and 8.4 GHz of the compact symmetric object (CSO) OQ208. Images taken on four epochs at 5GHz and one at 8.4GHz show that the parsec radio structure of the source consists of two mini-lobes, both of them are resolved into two hot-spots. We note that the component D is stronger than the component C in the south-west region at 5 GHz, indicating that component D is less free-free absorbed than C at low frequency. On the basis of the separation of components A and D, a proper motion of 0.032±0.02 mas yr~(-1) between the two mini-lobes is estimated. This value is about half the previous estimates based on the separation of components A and C with 8.4 GHz VLBI data. The reason for the decrease in the expansion velocity is discussed. 相似文献