Aeromagnetic Anomalies over the Area of Unzendake Volcano
Aeromagnetic Anomalies over the Area of Unzendake Volcano
复制标题
云仙岳火山地区的航磁异常
DOI：
10.5636/jgg.46.529
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
T. Nakatsuka
中科院分区：
文献类型：
--
作者：
T. Nakatsuka
1991年8月，在这次喷发开始后，对温曾达克火山地区进行了航空磁力测量飞行，并根据收集的数据绘制了地磁异常图。本文试图将磁异常与新能源开发组织1981年的磁异常进行对比，以判断这10年来磁异常的形态是否发生了明显的变化。然而，没有发现波长超过6公里的大的变化。该区的磁异常与地形有密切的关系。通过统计分析，估计正常磁化地形的平均磁化强度为2.9 A/m，并消除了地形起伏的影响。剩余的解释与磁性火山岩和较浅的横向磁化不均匀性填充的地堑结构。并指出猿山周围未知的古老火山单元可能在地表下有相当大的延伸。
An aeromagnetic survey flight over the area of Unzendake volcano was conducted in August, 1991, after the commencement of this time eruption, and a geomagnetic anomaly map was derived from collected data. The comparison of magnetic anomalies with the ones in 1981 by the New Energy Development Organization was attempted in order to judge whether there was a significant change of magnetic anomaly pattern for these ten years. However, no large variations with wavelengths more than 6 km were detected. The magnetic anomalies of the area revealed a close correlation with the topography. Average magnetization of normally magnetized terrain was estimated to 2.9 A/m from statistical analysis, and the effect of topographic relief was removed. The residuals were interpreted in terms of a graben structure filled with magnetic volcanics and shallower lateral inhomogeneity of magnetization. And the possibility was pointed out that an old volcanic unit unknown around Sarubayama might have considerable extension under the surface.