Issued Patents 1989
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4879463 | Method and apparatus for subsurface formation evaluation | Edouard Marienbach, Jean-Michel Hache, Erik Rhein-Knudsen, Mike Evans | 1989-11-07 |
| 4845359 | Methods and apparatus for safely handling radioactive sources in measuring-while-drilling tools | — | 1989-07-04 |
| 4814609 | Methods and apparatus for safely measuring downhole conditions and formation characteristics while drilling a borehole | Edouard Marienbach, Jean-Michel Hache, Erik Rhein-Knudsen, Mike Evans | 1989-03-21 |
| 4810876 | Logging apparatus and method for determining absolute elemental concentrations of subsurface formations | Russel C. Hertzog, Darwin V. Ellis, Hubert D. Scott, Jeffrey S. Schweitzer, James A. Grau | 1989-03-07 |