parallel positive and negative anomalies. The bathymetric contour 

 chart (figure 6) shows a series of small bathymetric features paral- 

 leling the strike of these anomalies. This bathymetric lineation 

 extends from Caicos Passage to a point approximately 80 nautical miles 

 to the northeast. A computer program for polynomial fitting of 

 surfaces by least squares will be used to determine whether the 

 magnetic trend extends to the southeast into Caicos Passage. Esti- 

 mates indicate that the top of the source of these magnetic anomalies 

 is between 3 and 4 nautical miles below sea level. 



The linearity, extent, and direction of these three magnetic 

 anomalies suggest that this area is the focus of three major faults 

 or fault zones. At least one, in the southern part of the area, 

 appears to occur in the basement. 



An interesting magnetic anomaly is found in the extreme eastern 

 corner of the survey area. This anomaly (shown in figure 3) has steep 

 gradients and high amplitudes, but no bathymetric feature is associ- 

 ated with the anomaly. Depth estimates using empirical methods indi- 

 cate a depth of approximately 5 nautical miles to the top of the 

 source of the anomaly. This depth is about 2 miles below the present 

 ocean floor. 



B. Enroute Survey 



An additional 2350 nautical miles of geomagnetic and bathymetric 

 data were collected concurrently while proceeding along tracks to and 

 from the survey area. This information is presented in profile form 

 in figures 7 through 16. Profile locations are shown in figure 1. 



