1068 



Subsurface Geologic Methods 



1.0 



5.0 



10.0 



15.0 



Contour interval=0.5 m.g. 



Figure 562. Gravity contours of an area in west Texas showing anomalies at A and 

 B due largely to density contrasts between red beds and limestone at depth of 

 approximately 4,000 feet. Both anomalies outline known structures. (After 

 Coffin. Reproduced permission Am. Assoc. Petroleum Geologists.) 



