58 



Subsurface Geologic Methods 



D . H ' 



Figure 26. A — Accumulation in porous beds below an erosional surface overlain by 

 impervious strata. A common variety of fault and lens trap is also shov\rn. The 

 reservoirs represent both stratigraphic and stratigraphic-structural types. B, C, 

 D, E — Accumulations attributed mainly to structural control. F, G— Structural 

 and stratigraphic-structural relationships that account for accumulations. H — 

 Accumulation that has been controlled by structural conditions. 



