Subsurface Logging Methods 



389 



Figure 171. Portion of electrical log showing typical profile pattern of a section con- 

 sisting of thin interbedded sandstones and shale (Cretaceous of "Wyoming). 



Figure 172. Portion of electrical log showing typical profiles produced by an oil sand, 

 and a comparison with the core record and core analysis (Mississippian of Illi- 

 nois) . 



