A Time Saving Method for Determining the Characteristic Shape and Strike of Oceanic Magnetic Anomalies.

摘要

Magnetic surveys have revealed interesting patterns of peculiar character of magnetic anomaly in widely separated parts of the ocean. The practice of obtaining the magnetic anomaly picture for an area of ocean by means of a close grid, two-dimensional survey has been very expensive of ship and personnel time. In view of the expense, there has been hesitation to extend our surveys in many places of interest. Recently, in order to make better use of the limited time during the Risepac expedition, a semistatistical method was attempted for determining the anomaly character of a particular area. The method turned out to be quite satisfactory for obtaining a two-dimensional character picture of the anomaly along a ship's track between ports with little loss of good time to the ship's progress. About one day of good time is lost per thousand miles of track. This may vary by a factor of two either way depending on the particular stretch of ocean covered.