Fig. 5From: Evaluation of deep geothermal exploration drillings in the crystalline basement of the Fennoscandian Shield Border Zone in south SwedenExamples of the used drill bits in FFC-1. To the left, PDC (Z613) used between 2319 and 2338 m, and to the right TCI roller cone bit (637Y) used between 2413 and 2416 m. Photo J-E RosbergBack to article page