| 摘要 |
A system (1) for drilling a borehole in an earth formation is disclosed, the system (1) comprising a first sub-system (I) including a drill string (3) extending into the borehole, and a second sub-system (II) including a drive system for driving the drill string (3) in rotation about the longitudinal axis thereof. Each one of said sub-systems has a rotational resonance frequency, wherein the rotational resonance frequency of the second sub-system (II) is lower than the rotational resonance frequency of the first sub-system (I). <IMAGE> |
