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351.
In this paper, the Electrical Resistivity Tomography and magnetic methods, including Tilt Angle and Euler Deconvolution, have been used in a comperative manner to determine the lineaments and depths of buried archeological structures. The zero contours of the tilt angle correspond to the boundaries of buried structures and the half distance between ±π/4 rad corresponds to the depth to the top of the structures. Also, in order to estimate the positions and depths of buried structures in the study area, the Euler Deconvolution method was applied to the total magnetic field data. All of the methods have a good correlation about determination of the horizontal locations and depths of the buried structures. The archeological excavations based on the geophysical investigations have demonstrated that the buried structure is an ancient cistern building because of the unearthed pools. Therefore, the interpretations of the geophysical methods and fiction of the paper were made according to the ancient cistern building. With this study, a buried ancient cistern structure was modeled and revealed by the geophysical methods for the first time. Additionally, using of these geophysical techniques in a comparative manner for the archaeogeophysical work will greatly contribute to future studies.  相似文献   
352.
利用山东威海CINRDA/SA多普勒雷达探测资料,结合常规天气图资料、地面自动气象观测站资料等,对2018年9月8日发生在威海文登机场附近的一次下击暴流天气特征进行分析。结果表明:1)此次下击暴流天气发生在高低空一致的西北气流背景下,午后太阳辐射使得低空大气加热显著,形成了强烈的不稳定层结。2)大气层结特征呈喇叭状温湿分布,850 hPa以下接近干绝热的温度直减率,为下击暴流的发生提供了有利环境条件。3)地面辐合线为风暴单体的产生提供了动力抬升条件。4)从多普勒雷达产品上看,风暴初始回波发生在午后海风锋触发的晴空窄带回波上,通过单体间的合并加强,发展成为多单体风暴;下击暴流出现前,对流风暴回波强度及高度明显发展,成熟阶段的对流风暴伴有回波悬垂结构和三体散射特征,伴随着强反射率因子核心的持续下降,下击暴流迅速到达地面,径向速度图上存在明显的中层辐合、旋转、低层辐散的现象;5 km以上60 dBZ强反射率因子核心的下降,结合径向速度中层辐合、低层辐散特征可提前3~9 min预警下击暴流的发生。  相似文献   
353.
何灿  孙建平  程迁群 《地球学报》2013,34(S1):221-228
红土型镍矿为含镍基性-超基性岩体经红土化作用形成的地表风化壳型矿床, 具有矿床分布相对集中、矿床规模大、矿床勘查类型简单、找矿标志明显等显著特点。本文简要总结了红土型镍矿的成矿环境、成矿条件、地质特征, 在云南省有色地质局三〇八队“走出去”实施多个红土型镍矿找矿勘查实例的基础上, 系统对红土型镍矿的找矿、勘查评价方法进行研究和总结, 提出红土型镍矿的“三段五步法”找矿勘查程序、有效找矿方法和快速勘查评价模式, 并对红土型镍矿勘查评价中的相关问题进行了探讨。  相似文献   
354.
程迁群  汤俊  何灿  刘传高 《地球学报》2013,34(S1):71-75
新安里镍矿经过四年的勘查工作, 探获一中型镍矿床。新安里镍矿位于金沙江—哀牢山板块结合带南段之金平断块中, 产于基性-超基性岩体内, 矿体呈似层状、透镜状产出。通过区域地质特征、矿床地质特征、矿体地质特征分析, 矿床成因类型初步认为属产于超基性岩中的熔离铜镍硫化物矿床, 找矿标志为岩体分异程度、构造条件、物化探异常。有助于在云南其它地区基性-超基性岩中寻找同类型镍矿床。  相似文献   
355.
安徽铜陵市蕴含地质储量达15 000万t的低品位钙基膨润土,蒙脱石平均含量50%~80%,现主要用于附加值较低的球团土和铸造土。将这种低品位钙基膨润土先通过悬浮和挤压综合钠化改型工艺,再添加一定量的超高分子量聚丙烯酸钠(PAA-Na)和轻烧氧化镁(MgO)组成的有机无机复合增黏剂,以及由小分子水解聚丙烯腈钠盐与腐植酸接枝聚合的专用流变性调节剂(HmPS),制备出了符合水平穿越钻井(HDD)使用要求的高造浆膨润土。分析了钠化工艺和增效添加剂对HDD造浆土的黏度(600)、动塑比(YP/PV)、综合流变性能以及成本等的影响,优化得到了具有较好性价比的工艺配方。优化工艺下的HDD造浆土性能600读数大于100 dia,YP/PV小于1.5,30 min的API滤失量小于15 mL。铜陵钙基膨润土改性制备成HDD高造浆膨润土,可将产品附加值提高到1 000元/t左右,利润率提高2~3倍,实现了低品位膨润土资源的高附加值利用。  相似文献   
356.
In southeastern Turkey, the NE-trending Antakya Graben forms an asymmetric depression filled by Pliocene marine siliciclastic sediment, Pleistocene to Recent fluvial terrace sediment, and alluvium. Along the Mediterranean coast of the graben, marine terrace deposits sit at different elevations ranging from 2 to 180 m above present sea level, with ages ranging from MIS 2 to 11. A multisegmented, dominantly sinistral fault lying along the graben may connect the Cyprus Arc in the west to the Amik Triple Junction on the Dead Sea Fault (DSF) in the east. Normal faults, which are younger than the sinistral ones, bound the graben’s southeastern margin. The westward escape of the continental ?skenderun Block, delimited by sinistral fault segments belonging to the DSF in the east and the Eastern Anatolian Fault in the north caused the development of a sinistral transtensional tectonic regime, which has opened the Antakya Graben since the Pliocene. In the later stages of this opening, normal faults developed along the southeastern margin that caused the graben to tilt to the southwest, leading to differential uplift of Mediterranean coastal terraces. Most of these normal faults remain active. In addition to these tectonic movements, Pleistocene sea level changes in the Mediterranean affected the geomorphological evolution of the area.  相似文献   
357.
徐粲  高建华  杨旸  汪亚平  高抒 《海洋学报》2014,36(11):150-162
根据南黄海辐射沙脊群定点站位的流速和浊度数据,利用通量分解方法,分析了潮汐水道的悬沙输运特征和输运机制。结果表明,辐射沙脊群海域潮汐水道中潮流为往复流,悬沙浓度较高,属于强潮流控制的悬沙浓度相对较高的陆架浅海环境;悬沙输运主要受欧拉余流和潮汐捕捉效应控制,再悬浮的沉积物通过平流作用进行输运。其中,陈家坞槽和西洋水道的悬沙输运以潮汐捕捉效应占优,沉积物向潮汐水道外输运,处于冲刷状态;苦水洋水道以欧拉余流输运为主,水道内的再悬浮的沉积物在强潮流作用下向陆输运,主要堆积在蒋家沙和西洋西侧岸滩等浅滩和潮间带上。由此可见,在陆源物质供应减少背景下,南黄海辐射沙脊群内部的物质充当了新的物源,短期内能够维持近岸潮滩和沙脊的持续增长。  相似文献   
358.
Abstract

This paper offers a teaching strategy for incorporating TIGER/Line files into introductory GIS courses where IDRISI and OSUMAP are the primary software packages. TIGER/Line files present a valuable database for teaching GIS. The TIGER data structure aids in teaching concepts related to topological data structures, geocoding and address matching, and the files themselves provide an excellent database for laboratory exercises that incorporate census information along with environmental and natural resource data. Lack of support by commonly-used educational software packages to import TIGER/Line files directly has been a serious impediment in an instructional context. This paper presents software developed to convert TIGER/Line files into simple polygon vector files acceptable by IDRISI and OSUMAP for three alternative census geographic units (tracts, block groups and blocks). The resulting vector files are plotted for visual examination and graphical output. The vector files generated can also be imported into other GIS or computer mapping software packages.  相似文献   
359.
Gallerias are the underground constructed results of mining. As these space in underground layers collapse, horizontal and vertical ground movements occur and movement which may reach the earth’s surface are known as mining subsidence. The result of underground displacement may cause surface ground movement which can be detrimental to masonry buildings especially in hard coal regions. Thorough familiarity with general and regional characteristics of an affected area can assist reduction of the effects. Zonguldak and the nearby settlement area, with a population of 300,000, constitute the centre of a hard coal basin where extensive mining has a history extending through 160 years. Mining constitutes the main economic activity in this region, and consequently influences every aspect of life. This study’s intent is to identify the effects of mining subsidence on masonry buildings in the mining area of Kozlu, Zonguldak, Turkey and illustrate them with selected images of damaged masonry buildings. Also included are satellite and mining galleria images.  相似文献   
360.
在深入研究重庆地票制度基础上,根据传统地票交易管理模式,设计了基于互联网的B/S构架系统,实现了交易信息推送发布、交易管理、态势分析和收益分配溯源等一系列功能,构建了土地流转网上交易平台,并依托课题项目在重庆城乡统筹示范区开展农村土地流转过程数字化监管技术集成及应用示范,替代纯文本、纯人工的工作管理环境,以一体化的数据管理方式为土地流转的管理和相关决策提供信息化手段与支持。  相似文献   
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