(under subclass 82) Subject matter wherein the inaccessible environment is a hole drilled in the earth (e.g., an exploratory well).
SEE OR SEARCH CLASS
33, Geometrical Instruments,
302, and 304+ for borehole directions indications.
73, Measuring and Testing,
152.01+, for instruments for borehole studies.
166, Wells,
64, and 66 for well apparatus including measuring, testing, or indicating means and subclasses 250.01+ for well processes including measuring, testing, or indicating. 175, Boring or Penetrating the Earth,
40+, for a process +or means of measuring or testing combined with an earth boring process or apparatus.
181, Acoustics,
102+, for well exploration by use of seismic prospecting systems which do not involve the handling of electric signals that contain geophysical information.
250, Radiant Energy,
256+, for ray energy detection or measurement (including detection or measurement of radioactive materials) applied to a borehole or drilling study.
324, Electricity: Measuring and Testing,
323+, for electrical testing of boreholes.
340, Communications: Electrical,
853.1+, for telemetering in wells.
367, Communications, Electrical: Acoustic Wave Systems and Devices, 25+, for seismic well logging using acoustic wave responsive electrical means.
