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引言目前已有许多国家着手进行航磁填图工作,以便在合理的时间内完成他们国家的扫面工作。这项工作显然是很有意义的。例如苏联(Solov’geva,1968)于1967年以2公里的飞行间距完成了扫面工作。加拿大地质调查所也已开始了以1/2英里(804m)飞行间距对整个加拿大地盾进行填图。现在地盾区的将近3/4区域已经飞完,并且这些图件已经可以用于公开发行(Hood,1974)。在写这篇文章的时候止,还没有一个绘编美国的航磁资料的国家计划。到目前力止,出版发行的航磁图只占美国的20％。尽管全国至少已有一半的范围已经由私营企业进行了不同程度的测量工作,但这些结果还没有能公开发行。在美国,现有的大部分测量而积是由美国地质调查所提供的,其经费通常来自于其它机构,此为国家地质调查所等。最近几年来,美国地质调查所采取了一种政策,即通过公开文件(open-file)的途径来使航磁数据迅速得以发行。关于这方面,近来的发表物大部分是以1:250,000比例尺的资
Introduction Many countries have embarked on aeromagnetic mapping in order to complete the scanning of their country within a reasonable period of time. This work obviously makes sense. For example, the Soviet Union (Solov’geva, 1968) completed the sweeping operation in 1967 at a flying distance of 2 kilometers. The Geological Survey of Canada has also begun mapping the entire Canadian Earthquake at 1/2 mile (804 m) flight spacing. Nearly three-quarters of the area now covered by the Shields has already been flown, and these drawings are ready for public distribution (Hood, 1974). At the time of writing this article, there was no national plan to map the U.S. aeromagnetic data. Until now, aeromagnetic charts published and published accounted for only 20% of the United States. Although at least half of the nation’s scope has been measured by the private sector to varying degrees, these results have not yet been publicly released. In the United States, most of the existing measurements are provided by the United States Geological Survey, which usually comes from other agencies, such as the National Geological Survey. In recent years, the United States Geological Survey has adopted a policy of making aeromagnetic data available quickly through open-file access. In this regard, the majority of recent publications are on a 1: 250,000 scale