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361.
商业导购电子地图作为面向专题应用的一个新型地图产品形式,值得我们关注与探讨.本文从其设计思想和设计原则出发,初步探讨了商业导购电子地图的建立、表达与应用,并采用自行开发的电子地图设计平台--声图系统VoiceMap2005,构建了南京市湖南路商业导购电子地图.  相似文献   
362.
海水面的虚反射(鬼波)引起海上拖缆采集数据陷波,导致地震记录频带变窄,而近年发展的变深度缆采集技术,具有多样的陷波特征,通过专门的去虚反射处理方法可获得宽频数据.本文基于已有研究成果,将最小二乘反演迭代压制虚反射算法应用于某海上变深度缆宽频处理.基于频率波数域镜像记录生成方法获得镜像炮集记录,并采用最小二乘解从变深度缆原始和镜像炮集记录中提取上行波.针对镜像炮集记录生成受初始速度模型精度的影响,使得某深度缆接收的上行波和下行波之间的实际延迟时间存在误差,采用最小二乘反演迭代算法最优化计算下行波与上行波之间的平均延迟时间和上行波记录,并采用时空数据窗口滑动克服延迟时间随炮检距和目的层深度变化问题.合成数据及某海上实际变深度缆数据处理测试结果表明,该方法能较好地压制变深度缆由海水面产生的虚反射,能达到拓宽地震记录频带目的.  相似文献   
363.
郭建兴  王晓青  窦爱霞  袁小祥  张伟 《地震》2013,33(2):123-131
破坏性地震发生后, 利用获取的灾区遥感影像资料进行灾情判断, 可以为地震应急和救援指挥决策提供重要依据。 通常, 遥感影像要经过复杂的制图、 传输、 打印等才能提供给应急指挥部门, 降低了实效性。 数字地球显示平台不但操作简单, 而且信息显示丰富。 本文提出利用遵循OpenGIS软件规范的开源WebGIS服务器和开源数字地球客户端构建地震应急遥感震害信息发布系统的解决方案, 并以2012年云南昭通彝良地震为例, 实现了GIS数据和遥感影像的在线发布和三维显示, 结果显著提高了地震应急遥感震害信息的浏览显示效果, 为应急灾情判断提供了有用的工具, 在地震应急救援工作中具有重要的应用潜力。  相似文献   
364.
文章对采自华北板块山东潍坊、河北唐山和辽宁大连的寒武系开腔骨类化石的新材料进行了研究,这些化石鉴定为 Chancelloria 属。辽宁大连地区的Chancelloria 产自寒武系第二统第四阶馒头组下部的黄绿色页岩;山东潍坊地区的 Chancelloria 产自苗岭统乌溜阶馒头组上部的黄绿色页岩和鼓山阶张夏组的深灰色中厚层灰岩;河北唐山地区的Chancelloria 产于芙蓉统江山阶长山组的薄层灰岩,该层位是目前Chancelloria 属在中国产出的最高层位,也是全球的最高层位之一。这 些来自华北寒武系第二统-芙蓉统的Chancelloria 骨片与早期的骨片相比,展现出骨片形态趋于规则、基面从浑圆趋于平 整、骨片整合度提升的特点,进一步印证了之前关于此类问题的研究结论。  相似文献   
365.
《China Geology》2019,2(3):261-275
The Sinian Doushantuo Formation is the oldest shale gas reservoir discovered in the world, which contains good shale gas shows as the Eyangye-1 and Zidi-1 wells in the Yichang Region of western Hubei province, China. The shales in the Doushantuo Formation feature considerable thickness (135 m), high gas content (4.83 m3/t) and high fragile mineral content (up to 75%). Due to the influences of the sedimentary environment, the shale reservoirs here have high dolomitic content (54%) and abruptly changes in vertical lithofacies. Moreover, the characteristics of the shale sweet-spot differ significantly from that in the Wufeng Formation and Longmaxi Formation in southeast Sichuan Basin. A high-resolution sequence stratigraphic correlation was performed on the shales of the Doushantuo Formation at the Eyangye-1 well, Zidi-1 well, Zidi-2 well and some outcrop profiles in Yichang area for the identification of their sedimentary microfacies characteristics. A comprehensive comparative analysis was made by incorporating the elemental geochemistry, wireline and mud logging data of the well to further identify the sweet-spot interval therein. With the analysis of Eyangye-1 well, the sweet-spot interval of the Doushantuo Formation is 3360−3408 m, of which sedimentary microfacies is deepwater reduced environment with many pyrite laminaes, and the TOC is high to 3.42%, the Ro is 3.3%, the organic and matrix pore are well developed and the aperture more than 50 nm, the porosity is 2.7%, the desorption gas content average is 2.16%, and the main mineral is dolomitic (54%) and siliceous quartz (21%). Additionally, these parameters combined with previous studies will shed light on evaluating and characterizing the layers therein, also provide referential geological data for the following exploration and development activities of this shale system.  相似文献   
366.
地理信息公共服务平台建设的有效驱动   总被引:1,自引:0,他引:1  
通过研究我国地理信息公共服务平台建设的驱动现状及其相关问题,分析了地理信息公共服务平台的层次结构以及在空间信息技术发展中的定位,基于地理信息公共服务平台的试点工程应用示范建设的经验,阐述了地理信息公共服务平台建设的有效驱动问题。针对我国当前地理信息公共服务平台建设中的瓶颈问题,提出了走以不同行业与部门协同共建的方式来有效驱动地理信息公共服务平台建设的路径。  相似文献   
367.
The pores in shales are mainly of nanometer-scale, and their pore size distribution is very important for the preservation and exploitation of shale gas. This study focused on the organic-rich Lower Silurian black shale from four wells in the Upper Yangtze Platform, and their TOC, mineralogical composition and pore characterization were investigated. Low pressure N2 and CO2 adsorption were conducted at 77.35 K and 273.15 K, respectively, and the pore structures were characterized by modified Brunauer-Emmett-Teller (BET), Dubinin-Radushkevich (DR), t-plot, Barrett-Joyner-Halenda (BJH) and density functional theory (DFT) methods and then the relationship between pore structure and shale gas sorption capacity was discussed. The results indicate that (1) The Lower Silurian shale has high TOC content of 0.92%–4.96%, high quartz content of 30.6%–69.5%, and high clays content of 24.1%–51.2%. The total specific surface area varies from 7.56 m2/g to 25.86 m2/g. Both the total specific surface area and quartz content are positively associated with the TOC content. (2) Shale samples with higher TOC content have more micropores, which results in more complex nanopore structure. Micropore volumes/surface areas and non-micropore surface areas all increase with the increasing TOC content. (3) A combination of N2 and CO2 adsorption provides the most suitable detection range (~0.3–60 nm) and has high reliability and accuracy for nanopore structure characterization. (4) The TOC content is the key factor to control the gas sorption capacity of the Lower Silurian shale in the Upper Yangtze Platform.  相似文献   
368.
This work focuses on the 3D modeling and structural analysis of the Monte Testo syn-sedimentary structure, developed in the Early Jurassic Calcari Grigi Group of the Trento carbonate platform (Southern Alps, Italy). Significant changes in the facies architecture of the platform sedimentary units, occurred across a global perturbation of the Carbon cycle at the Sinemurian-Pliensbachian boundary, are associated with evidences of syn-sedimentary tectonics. In particular, an early cemented oolitic sedimentary body with a high initial porosity (Loppio Oolitic Limestone) was broken-up and tilted by a pulse of rifting and overlain by tight marls and marly limestones (lower Rotzo Formation) that display sharp changes in thickness across the syn-sedimentary faults. This complex setting creates conditions potentially favorable to hydrocarbon accumulation. In this work, the Monte Testo structure is presented as a conceptual analogue of a hydrocarbon reservoir that may develop thanks to the overlap of the effects of extensional tectonics and climate change-induced modifications in the carbonate platform facies. A 3D geo-model was realized to obtain information about the genesis and tectonic evolution of the structure. Hence, a potential porosity distribution in the 3D model was evaluated showing that such extensional structure, which has a vertical extent of 500 m and covers an area of 15 km2, could have been associated to a total pore volume of 2.24 × 107 m3 at the time of its formation. Results suggest that in rifting contexts the combined effect of syn-sedimentary faulting and facies variations related to perturbations in the global carbon cycle could generate potential reservoirs in carbonate platforms.  相似文献   
369.
锆石U-Pb定年及Hf同位素测定结果表明,鄂尔多斯盆地周缘的华北板块北缘、兴蒙造山系及扬子板块-秦岭-大别-苏鲁造山带等构造单元系统具有明显不同的形成与演化历史。华北板块北缘锆石年龄平均值为1 837 Ma,最强烈的岩浆活动出现于2 200~1 800 Ma,该期锆石约占全部的40%;次为强烈的岩浆活动在2 800~2 200 Ma,其众数在全部锆石中约占30%;1 500~1 200 Ma、500~100 Ma这两个阶段形成的锆石在全区所占比例各约为15%。华北板块北缘最突出的特征是基本不含1 000~700 Ma期间形成的锆石,>3 000 Ma的锆石在全区分布极为有限。锆石Hf同位素亏损地幔模式年龄表明华北板块北缘平均值为2.55 Ga,较U-Pb平均年龄老,说明2 200~1 800 Ma期间形成的锆石含有较多的古老地壳再循环组分。Hf亏损地幔模式年龄最强峰值约为2.8 Ga,与全岩Nd亏损地幔模式年龄的峰值相一致,Hf模式年龄为3.0~2.25 Ga的颗粒占全部的近95%,证明华北板块北缘的地壳增生主要在太古宙至古元古代期间。Hf同位素亏损地幔模式年龄>3.0 Ga的锆石颗粒所占比例不到0.1%,另外近5%锆石的模式年龄分布于中元古代。晚古生代-中生代所形成的锆石均是先存地壳组分,尤其是中元古代增生地壳的熔融作用形成。兴蒙造山系中锆石U-Pb年龄平均值为497 Ma,最强峰分布于石炭纪(约320 Ma),石炭纪-二叠纪末(350~250 Ma)形成的锆石所占比例达30%以上。新元古代至早古生代(600~440 Ma)形成的锆石占全部锆石的55%以上,而中元古代末-新元古代期间(1 200~600 Ma)形成的锆石在全区仅占4%。中元古代以前形成的锆石非常有限,说明该区最早形成的地壳组分在兴蒙造山系的形成过程中较充分地参与到后期的岩浆作用过程中。兴蒙造山系中锆石相应的Hf同位素亏损地幔模式年龄平均为1.13 Ga,明显较相应的U-Pb年龄老,最强峰值出现于约0.6 Ga。Hf亏损地幔模式年龄为0.7~0.28 Ga的颗粒在兴蒙造山系所占比例达57%,证明该区最强烈的地壳增生发生于新元古代至古生代期间。Hf同位素亏损地幔模式年龄分布于1.5~0.7 Ga的锆石在全区约占38%,说明此期间也是该区地壳较强烈的增生期。Hf亏损地幔模式年龄大于1.5 Ga的锆石所占比例不到5%,古生代以后兴蒙造山系也基本没有明显的地壳增生。扬子与秦岭-大别-苏鲁造山带构造单元中的锆石U-Pb年龄平均为799 Ma,年龄为1 300~750 Ma的锆石在全部锆石中约占70%。晚古生代-燕山期形成的锆石约占20%。年龄在3 500~2 650 Ma、2 118~1 680 Ma的锆石在该区各约占5%。结合扬子与秦岭-大别-苏鲁造山带平均为1.56 Ga的Nd亏损地幔模式年龄特征,说明1 300~750 Ma期间该区较强烈的岩浆作用事件中有较多的古老地壳组分加入其中。锆石U-Pb年龄及Hf同位素组成均说明鄂尔多斯盆地周缘各构造单元具有不同的形成演化历史。地壳是幕式增长的,但各构造单元每幕发生的时间、强度存在明显差别。因此,由盆地中不同时代地层中碎屑锆石U-Pb年龄及Hf同位素组成及全岩Nd同位素特征的系统研究可反演盆地物源供给与周围构造单元之间的关系。  相似文献   
370.
More than 20 K-bentonite beds were discovered from the Wufeng Formation and the lowest Longmaxi Formation in two sections, both adjacent to the Ordovician-Silurian (O-S) boundary and located in Tongzi, Guizhou Province and Yichang, Hubei Province, some 500 km apart from each other in South China. This indicates that many volcanic eruptions occurred near the southeast margin of the Yangtze Platform between the latest Ordovician and the earliest Silurian. Mainly through biostratigraphic and sequence stratigraphic studies, it was found that almost all these far-apart K-bentonite beds may be correlated with each other. This is the first time that a succession of volcanic ash deposits with high potential of correlation was discovered within a strata interval on the main platforms of China. Therefore, these K-bentonite beds may afford excellent event-marker beds helpful to high-resolution research in integrated stratigraphy as well as other lines of research on the O-S boundary in South China.  相似文献   
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