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航磁在西南三江地区铜矿勘查中的作用探讨 总被引：1，自引：0，他引：1
本文探讨了西南三江地区航磁资料二次开发研究进行地质找矿的有效性。通过对玉龙铜矿磁异常特征的理论分析,在建立矿床磁性模型的基础上,探讨了利用航磁资料寻找斑岩型铜矿的有效性。最后采用定量分析方法进行了以航磁、遥感信息为主的综合信息找矿预测。 相似文献
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目前,利用航磁数据圈定磁性地质体边界的方法主要有航磁ΔT化极法、航磁ΔT化极垂向一阶导数法、总梯度模法和斜导数法等4种。云南宣威-贵州赫章地区火山岩分布面积广泛,下二叠统峨眉山玄武岩具有强磁性,而其他地层岩石磁性很低;为了圈定研究区内磁性地质体的目的,利用该区1∶5万航磁测量数据,阐述了ΔT化极法、化极垂向一阶导数法、斜导数法和总梯度模法等4种数据处理方法的地质应用效果,认为应根据有效磁化方向与地磁场方向是否一致来选用不同的航磁数据处理方法,以达到有效圈定地质的目的。 相似文献
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航磁补偿飞行中,飞机姿态变化产生的磁场严重影响航磁数据精度。为了补偿飞机产生的磁干扰,基于Tolles-Lawson方程建立补偿模型,其中关键是计算方向余弦值;采用Leach提出的基于三轴磁通门解算方向余弦方法建立航磁补偿系统;依据当地水平坐标系与飞机坐标系之间的旋转关系,建立了机载三轴磁通门数据的理论模型解算方向余弦,从而验证了该补偿方法的有效性。将该方法运用到云南某实验场地的航磁补偿数据中,并选择标准差作为评价补偿效果的指标,得到补偿质量满足规范要求,说明基于磁通门估计的航磁补偿方法是有效的。 相似文献
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在引进高精度航磁梯度测量系统的基础上,对潮水盆地某地区进行航磁梯度测量飞行。介绍了试验飞行中航磁梯度数据采集与处理过程,并对测量资料进行初步分析.通过对航磁梯度和航磁总场资料的对比,发现航磁梯度场相对航磁△T总场而言,异常更加明显;航磁梯度能更准确地确定磁性体的边界和断裂构造的位置,提供更多总场没有的信息,特别是实测的垂向梯度比计算的垂向一阶导数提供的信息更加丰富。因此引进高精度航磁梯度测量系统,无论是对今后的基础地质研究,还是矿产资源勘查等方面都有着广阔的应用前景。 相似文献
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航磁垂向梯度数据较航磁ΔT数据优势明显,可以有效识别地磁场的微弱变化。辽南瓦房店地区40%的金伯利岩体具有明显的梯度异常显示,可验证航磁垂向梯度技术在金刚石找矿中的有效性。本文通过分析瓦房店地区获取的大比例尺航磁垂向梯度资料,研究航磁垂向梯度异常特征与已知金伯利岩体产状的关系,发现岩体多位于NEE向孤立梯度异常中,岩体走向与异常走向基本一致,异常形态多表现为拉长的椭圆状,长轴走向多为NEE向,异常梯度值一般不大于150 nT/km,异常规模通常比地表出露范围大,对岩体的分布范围反映清晰。区内地质背景相似的NEE向航磁梯度异常对今后的金刚石矿勘查部署具有重要的指导意义,建议结合其他地质资料优选重点异常,布置大比例地面磁法、电法等地球物理方法查明引起异常的原因并评价其找矿前景。 相似文献
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梧南航磁异常区位于新疆维吾尔自治区鄯善县,该异常区于1978年发现两条近于平行的正磁异常带沿北西西向展布,航磁异常特征非常明显。笔者通过对梧南地区地质构造特征、成矿环境、岩(矿)石物性及航磁特征等进行综合分析、研究,探讨了梧南地区航磁异常引起的原因,进而推断两条沿北西西向展布的航磁异常带上,叠加的几处局部升高强磁异常可能与隐伏的磁性体有关。鉴于此,笔者以异常带上的新C-1978-127航磁异常为例,对航磁异常进行定性分析,并利用2.5D拟合技术进行定量拟合计算,推断航磁局部强磁异常可能与隐伏的磁铁矿有关。依据区内地质-地球物理特征、航磁定性分析及定量计算结果,建立了该区地质-地球物理找矿标识,并进行了找矿远景分析,认为区内新C-1978-127、127-1、127-2、127-3、127-4等5处局部强磁异常找矿潜力较大,应予以重视。 相似文献
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目前航磁异常的计算机检测手段单一,现有检测方法停留在定性研究的水平上,无法适应实际需要。为了克服这些局限性,将航磁异常计算机检测结果从定性水平提升到定量水平,这里提出了将图像处理中的离散KL变换方法应用于航磁轴向异常检测的新思想。经实地实例检验,效果良好,这一思想对研究航磁异常计算机检测有一定的借鉴意义。 相似文献
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寻找一种基于位场性质的、能将区域场与局部场较为客观地分离开来的方法,一直是许多地球物理工作者的努力目标。本文提出了一种最小均方误差线性滤波方法。它是根据所要研究区域的位场特点设计的。用此法对直立棱柱组合模型场进行了试算,并用南京-铜陵地区航磁资料进行实际计算,均取得了较好的效果。在此基础上,结合化极、垂向二次导数等处理方法,就有可能对大面积的航磁资料作出较为合理和确切的地质解释。 相似文献
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Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
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The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts 总被引：4，自引：0，他引：4
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species. 相似文献
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Muriel Rocher Stéphane Baize Stéphane Jaillet Edward Marc Cushing Yannick Lozac&#x;h Francis Lemeille 《Comptes Rendus Geoscience》2003,335(8):701-708
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003). 相似文献
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正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level 相似文献
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正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7), 相似文献
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正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci- 相似文献
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正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli- 相似文献
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正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.) 相似文献
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正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861 相似文献