616 



Subsurface Geologic Methods 



f 



Ml 



fCOREBARREL" 



» -1 





■ANCHOR 



W 



* Js- 



r '. 



B 



ii 



Figure 319. A — Hard-formation electric-motor-driven side-wall coring device. B, C — 

 Side-wall coring tools in which core tubes are driven into formation by an elec- 

 trically detonated charge. 



