MAGNETIC VECTOR STUDY IN OIL STATES 25 
The positive vector at Jackson indicates a magnetic “high” 
slightly southeast of the town. This “high” is due to an igneous plug, 
supposedly nepheline-syenite, and is in agreement with magnetometer 
surveys of the well known gas field. An interesting west-east trend of 
magnetic “‘highs’’ extends from Fayette to Ellisville. 
In general, there are hardly more than two vectors in Mississippi, 
which can be definitely attributed to the same structure. This circum- 
stance may be interpreted as due to local and relatively shallow 
sources of magnetism, which should be favorable for detailed investi- 
gations by the magnetometer. 
ALABAMA! 
From the northeastern corner of Alabama, a magnetic high trend, 
extending southwest to Greensboro, indicates the southern extension 
of the Appalachian Mountains. 
The vectors of the stations surrounding Greensboro are all positive 
and indicate by their direction that a large continuous positive anom- 
aly exists, covering that part of the state, which is explained as the 
“southernmost tip of the folded Appalachian Mountains” by D. R. 
Semmes.” 
This ‘“‘high” is an example of a large magnetic anomaly, corre- 
sponding with an extended structural feature, which could be cor- 
rectly interpreted by the study of the vertical intensity alone.® 
Another outstanding feature is the “low” at Wetumpka. This 
“low” may lie along a low trend Center-Anniston-Talladega-Rock- 
ford-Wetumpka, with the high trend Guntersville-Greensboro on the 
west and another high trend on the east, which would pass near Ash- 
land, Dadeville, and between Tuskegee and Wetumpka. 
In the southern part of the state a low trend is indicated between 
Georgiana and Greenville, extending northwestward toward Camden 
and southeastward toward Elba. Another possible low trend lies east 
of Tuskegee, Union Springs, and Troy. 
The positive vectors at Opp, Geneva, and possibly also at Ozark 
and Abbeville appear to be due to localized ‘‘structures,”’ which might 
be of interest for oil and gas possibilities, because they lie in the Gulf 
Coastal belt. 
1 The local magnetic vectors are based on the information given in ‘‘United States 
Magnetic Tables and Magnetic Charts for 1925,” op. cit. 
2D. R. Semmes, Geol. Survey of Alabama Bull. 22. 
3 L. Spraragen, op. cit. 
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