Sun charts were developed to permit straight line traversing by compass through areas of intense local magnetic disturbance. These charts facilitated rapid reconnaissance ground geophysical surveying of small aeromagnetic anomalies and, indeed, at times proved quite valuable to the exploration program. The magnetic correction can be determined from the sun charts in less than 1 minute, and the resulting accuracy is within 4 degrees .

First Page Preview

First page PDF preview
You do not currently have access to this article.