Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4458944 | Formation of in situ oil shale retort in plural steps | — | 1984-07-10 |
| 4366987 | Method for forming an in situ oil shale retort with horizontal free faces | Thomas E. Ricketts | 1983-01-04 |
| 4239284 | Situ retort with high grade fragmented oil shale zone adjacent the lower boundary | Richard D. Ridley | 1980-12-16 |