MAGNETIC VECTOR STUDY IN OIL STATES II 
In studying these local vector maps, it should be considered that, 
as shown in Figure 1, there exists somewhere along the prolongation 
of the horizontal vector either a magnetic “high” or “low,” which 
corresponds with some kind of geologic feature, either of structural 
or petrographic character. 
The great and irregular variations of the total intensity and of the 
directions of most of the horizontal vectors should make it clear that 
most of these features necessarily must be localized. 
This is the reason why no attempt has been made to connect the 
stations by certain curves, indicating, for example, equal total in- 
tensities, equal angles of inclination or equal vertical and horizontal 
intensities, though by help of the vectors the last two sets of curves 
could, of course, be much more intelligently computed than from the 
vertical or horizontal components alone. 
A few of the regional geologic “‘structures’’ can be quantitatively 
interpreted by the help of these vectors. 
Due to the long distances between stations, it has been necessary 
to use the most reasonable geological interpretation of the vector 
maps. Though two, three, or more local “‘highs’’ and ‘“‘lows” are 
possible between two neighboring stations, it is probable that re- 
gional geologic “structures” extend at right angles to the horizontal 
magnetic components, where the majority of the latter are nearly 
parallel with one another over a large area, that is, a common geologic 
feature is probably responsible for a series of vectors, if they are all 
directed toward, or away from, the same point. 
Due to the long distances between stations, the interpretation 
was mainly restricted to regional magnetic anomalies, though it is 
expected it will be found that the main value of the vector maps lies 
just in these areas, where the magnetic anomalies are so localized, or 
so shallow that no relation between the individual vectors can be 
established. 
For all those areas where the vectors indicate regional magnetic 
tendencies, we may reasonably assume that the vectors are mainly 
due to deeply buried regional structure. But if the main magnetic in- 
fluence in these areas originates at great depths and if the total inten- 
sity of the vectors amounts to only a few hundred gammas, we must 
conclude that the average magnetometer surveys can not possibly 
yield much information with regard to commercial structure, unless 
the deeper structure is truly reflected within the shallower beds. The 
results of the average magnetometer surveys are comparable with the 
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