| 摘要 |
<p>904,011. Geophysical surveying. SUN OIL CO. Aug. 21, 1958 [Sept. 23, 1957], No. 26978/58. Class 37. Bore hole logging apparatus comprises a flexible probe 14 mounted so as to be lowered down a hollow drill stem, the drill bit 252 being provided with a deflector 260 to guide the probe 14 into a non-central passage 254 through the drill bit 252. The recording apparatus carrying the probe 14 may be sensitive to resistivity and selfpotential as described in Specifications 904,012 and 904,013.</p> |
