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为解决介质圆柱体逆散射问题,提出一种新的在线逆散射方法,通过支持向量机将逆散射问题转化成一个回归估计问题. 该方法可应用于各种逆散射方面, 尤其是目标的几何与电磁参数重构和埋地目标探测. 文中首次将支持向量机方法应用到该领域,设置多个散射场的观测点,通过提取散射场的不同信息作为样本信息训练支持向量机, 建立了介质圆柱体的逆散射模型, 利用该模型重构了介质圆柱体的电磁参数,同时探测了埋地位置. 数值结果显示了该方法的有效性和准确性,为目标的实时逆散射研究提供了一种有效方法. 相似文献
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~(218)Po法寻找隐伏铀矿体初见成效 总被引:2,自引:0,他引:2
本文介绍了一种寻找隐伏铀矿体的快速测氡方法,即~(218)Po法。作者叙述了该法的工作原理、特点以及找矿效果,并阐述了~(218)Po法寻找隐伏铀矿体的可能性。最后着重叙述了~(218)Po法测量结果的解释方法。通过野外试验,作者认为:~(218)Po法不仅可以寻找隐伏铀矿体,而且能够定量预测盲矿体的埋藏深度与规模。 相似文献
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Chai Chizhang 《中国地震研究》2007,21(3):225-235
The paper introduces the steps and methods of multi-approach,multi-level exploration of buried faults in thick Quaternary sediment regions by taking the test exploration of the Yinchuan active fault as example.Based on the comprehensive analyses of previous data,we choose the Xinqushao Village of Xingqing District of Yinchuan City as the test site for the comprehensive exploration.Firstly,we adopted shallow seismic investigation with group intervals of 10m,5m and 1m to gradually trace layer by layer the master fault of the Yinchuan buried fault from a deep depth to a shallow depth where drilling could be used.Then,with composite geological profile drilling,we determined the precise location and dip angle of the fault.The drilling show the buried depth of the upper offset point is 8.3m.Finally,large-scale trenching revealed that the actual buried depth of the upper offset point of the fault is 1.5m from the ground surface and there are paleoearthquake events of 5 stages.Combined with the preliminary result of corresponding sample age,we conclude the Yinchuan buried fault is a mid to late Holocene active fault. 相似文献
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Little is known of Holocene landform development in Upland Britain. This paper describes a site at Middle Langdale in the Howgill Fells of Cumbria where large, but now stabilized and inactive gullies cut through periglacial material. At the base of the gullies large debris cones have buried earlier alluvial sediments on the valley floor. On these sediments and buried by the debris cones is a well-developed organic soil from which two 14C dates have been obtained in an attempt to estimate the age range of the soil. These dates range from 2580±55 years BP for the fine particulate fraction from the base of the organic horizon to 940±95 years BP for fossil rootlets from the uppermost organic layer, immediately below the overlying debris cones. The pollen evidence suggests that the valley floor site was initially dominated by alder carr and later by a Juncus marsh with birch, alder and hazel nearby. The pollen, from the surrounding upland area suggests woodland on the valley sides, dominated by oak and elm that was later replaced by a more open environment rich in heath species and in which disturbed ground species were present. The magnetic evidence indicates a stable local environment during soil formation but shows a sudden inwash of unweathered debris at the top of the buried soil. The evidence suggests that the valley floor was geomorphologically stable throughout the period of soil formation, although there was a local change in valley floor vegetation and a reduction of woodland cover on the valley sides at sometime during the period. The evidence then points to major geomorphological changes; a wave of soil erosion, gully development and debris cone deposition, perhaps following the Scandinavian introduction of sheep farming in the tenth century A.D. 相似文献
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高挂山—牛头寨地区,通过大比例尺航片解译,发现6个大小不等的小型环形影象信息。这些环形影象与岩浆活动、已知矿床、矿化点、重砂异常、物化探异常等的分布有着内在的联系。为预测找矿远景区和找隐伏矿床提供了影象依据。 相似文献
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超大型会泽富锗铅锌矿复合成因 总被引:4,自引:0,他引:4
会泽富锗铅锌矿。是近年老矿山深部找矿取得重大突破的典范,而其成因则是当前研究、讨论的热点。笔者认为该矿之形成,既非“MVT型”,亦非“VMS型”,而是与深部隐伏燕山期酸性岩有关的中温岩浆热液叠加、改造、富化的复成因矿床。自加里东期起长期处于张裂环境。深部昭通.弥勒硅镁层隆起,既是幔源玄武岩(热地幔柱)上涌的前奏,又为深部矿源上升创造畅通空间。与多旋回活动的小江深断裂相沟通的NE向矩形断裂网,是导矿、输矿、储矿的有利构造。继火山热液成矿之后,伴随燕山期褶皱、断裂和深部酸性岩浆的上升,发生第二期叠加矿化.矿石中伴生与酸性岩有关的元素组合.并以与酸性岩有关的锗富集为特征。 相似文献