884 



Subsurface Geologic Methods 

 Geologic Cross Sections 



Geologic cross sections should be included within subsurface geo- 

 logic reports whenever possible. An ideal cross section should incorporate 

 both an exaggerated and natural-scale profile. Many features of structure 



Figure 457. Cross section of Barbers Hill dome, a typical overhang salt plug; note 

 truncated and upturned sediments on flanks of intrusion; also arched overlying 

 section. In many areas of salt intrusion, faulting is extreme and complex. (Re- 

 produced permission Houston Geol. Soc.) 



and stratigraphy that cannot be illustrated on a natural-scale section may 

 be shown in exaggerated form; however, it must be remembered that such 

 sections distort true conditions. Suter ^ comments : 



Obviously in extreme cases of exaggeration, the tectonical and the strati- 

 graphical picture becomes meaningless, even in regions of moderate tectonics; 

 moderate dips can become almost vertical, et cetera. Geologists not accustomed 

 to exaggerated sections are apt to forget the fact of exaggeration and will 



^ Suter H. H., Exaggeration of Vertical Scale of Geologic Sections: Am. Assoc. Petroleum Geologists 

 Bull., vol. 31, no. 2, pp. 318-339, Feb. 1947. 



