Gravity and Magnetic Fields— -ROSE and Belshe 
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Fig. 5. Free-air anomaly map of the area north of Maui. 
map (Fig. 5) differs slightly from the map 
by Strange et ah (Fig. 3, p. 386 in this is- 
sue), and reflects the effect of later detailed 
data that were not available at the time their 
map was drawn. The map of the total magnetic 
field north of Maui is given as Figure 2 in the 
paper by Woollard in this issue (see p. 282). 
Figure 4 shows three profiles made by the 
"Surveyor” as north-south runs. The proposed 
Moho Hole site lies midway between the pro- 
files following 155°38 / W and 155°00'W. The 
three profiles have been aligned at the point in 
time where they cross 22°22'N. As indicated 
by Strange et ah, and as shown here, the pro- 
posed Moho Hole site lies very near the point 
where the free-air anomaly changes from a posi- 
tive field over the Arch to a negative field in 
the Hawaiian Deep. 
As the analysis of the earlier ("Gilbert”) 
gravity data by Strange et al. is not materially 
affected by the additional ("Surveyor”) data, 
these new data do not significantly alter the 
geological interpretation. The positive free-air 
anomaly near the proposed Moho Hole site can 
not be explained entirely by water-depth change 
and, as shown by Strange et al., can be recon- 
