C. Total Magnetic Intensity Contour Chart (Figure 2) 



The total Intensity values plotted on the Smooth Track Chart were 

 contoured at 50-gamma intervals. The contours are shown in Figure 2. 

 Dashed contours represent extrapolated data, 



D. Residual Magnetic Intensity Contour Chart (Figure 3) 



In order to more clearly define the anomalies, the regional 

 gradient of the total magnetic intensity was removed from the original 

 values. To accomplish this, the total intensity contours from H. 0, 

 Chart No. 1703, The Total Intensity of the Earth's Magnetic Force 

 (for the year 1955) were corrected to the year 1961 and then inter- 

 polated at 50-gamma intervals. These interpolated contours were 

 then reproduced on the total intensity contour sheet of the survey 

 area. At each point on the sheet where survey plot contour lines 

 intersected charted contour lines taken from H. 0. 1703, the differ- 

 ence was computed. If the survey contour value was greater than the 

 charted contour value, a plus (+) value was assigned to the differ- 

 ence; if smaller, a minus (-) value was assigned. An overlay was 

 placed over these two contour representations, and the differences 

 at contour intersections were plotted and contoured at 50-gamma 

 Intervals. The Residual Magnetic Intensity Contour Chart for the 

 survey area is shown in Figure 3. 



E. Profiles 



Profiles of the total magnetic intensity and the measured 

 bathymetrlc depth along each track are presented in Figures 4 

 through 12. These profiles were constructed using the smooth-plotted 

 survey tracks as base lines. An index to the geographical location 

 of each profile is shown in Figure 1. 



6 



