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PACIFIC SCIENCE, Vol. XX, July 1966 
area north of Maui does not change any charac- 
teristics of the major anomalies and only brings 
out low-amplitude, large- wavelength (10-20 
km) anomalies, as shown in Figure 8. 
Because the gradient of the regional mag- 
netic field over the Hawaiian Islands is low in 
comparison with the large amplitude of observed 
magnetic anomalies, no attempt was made to 
remove the regional magnetic field from the 
other areas studied. 
The Molokai Fracture Zone 
Menard (1964) shows that the Molokai 
Fracture Zone extends from the Baja California 
Seamount Province to the edge of the Hawaiian 
Deep, where the bathymetric expression of the 
fracture zone disappears. On the basis of bathy- 
metric data alone, this marks the terminus of the 
Molokai Fracture Zone. However, as will be 
shown, magnetic data suggest that it continues 
across the Hawaiian Ridge for a presently un- 
determined distance westward. 
By combining magnetic data taken by the 
U. S. Naval Oceanographic Office (1962), the 
University of Hawaii, and the Scripps Oceano- 
graphic Institute (Arthur D. Raff, unpub- 
lished), it is possible to relate magnetic anoma- 
lies to this and other prominent bathymetric 
features. As seen from Figure 9, the magnetic 
anomalies, as well as bathymetric features as- 
