A stratameter is a device for determining the original position and alignment of a drill core in deep drilling by marking the core with a compass and plumb line built into the core tube . The marker is necessary, as in the drill pipe existing twist makes it impossible to recover the core in its original position.
The stratameter is inserted into the borehole with the core tubing . The needle of the compass is locked in the compass at a time determined by a clockwork , so that the orientation of the core to the north remains traceable when the core is pulled out. The plumb bob marks the inclination of the drill core by dropping it once on a soft metal plate. Thus, the Bohrzeuges by means of the markings which are to catch up strike and dip of the layers determined.
- Description of the stratameter together with the plumb bob and representation of its various types of application in deep boreholes, freezer shafts, etc.: patented in Germany and many foreign countries / patent holder C. Otto . - Hildesheim: Borgmeyer. [approx. 1903]