| 摘要 |
<p>For the detection of the presence of metal or mineral there is used a two electrode probe insertable into the geological formation. The two electrodes are manufactured from different types of material. When one electrode contacts a metal or mineral grain, the contact potential thereof is changed and there is a change of voltage between the electrodes. The change of voltage is passed to indicator means. After amplifying and possibly filtering the signals resulting from the change of voltage the indicator means indicates the change of potential in one or several audio visual components. The magnitude of the change of potential indicates the type of metal or mineral that has been found.</p> |
