Research On The Technical Design In Marine Magnetic Survey

The key problems of the technical design in marine magnetic survey have been discussed and studied, the determination of the survey scale and the division of the map sheet have been brought forward. The mensuration of the magnetic effects of the boats has been perfected and the determination methods of the magnetic effects have been discussed. Furthermore, the techniques of the survey line design have been mainly discussed, the determination of the survey line direction and interval have been given out. The validity and the feasibility of the methods have been proved by the simulated data and observed data. The results can provide the theoretical grounds for the establishment of the Specifications for marine magnetic survey of China. The main works and creations are as following:(1) The progress of the technical design in marine magnetic survey are summarized and analyzed. The existent problems and solvable thoughts are pointed out.(2) The accuracy of magnetic anomaly map and the particular extent of the distribution of magnetic field can be related to the survey map scale, and also the survey efficiency, the selection rule of the map scale have been given out and the division of the map sheet with analytical method has been brought forward.(3)the theoretical method of calculation the draggle distance has been given out. The results show that the strength of magnetic filed of the vessel is changed with the course, when the course is 0° or 180°, the influence of the magnetic filed can be maximum. The measurement of magnetic filed of the boats have been standardized and perfected, including the eight course trailing, the tow cable length and tow deep.(4) For the calculating of the magnetic effect of the boats, the Fourier series are preceded to the four courses method.(5) The survey line direction must be along the total gradient direction of the magnetic anomaly of the area, and also the direction of perpendicular to the contour of the magnetic anomaly map. The relation of the interpolation precision and the survey line interval is build, the constant error and the scale error of marine magnetic survey have been applied to determine the survey line interval. The determination scheme has been given out.