| Relationships | Role | Relationship Start | Relationship End |
| Societe De Gestion Et D'interets Petroliers (Sogedip) | Parent | 12/31/1980 | 12/28/1984 |
| Compagnie Generale De Geophysique (Cgg) | Subsidary | 12/31/1980 | 12/28/1984 |
| Diamant Boart Us | Subsidary | 1/1/1982 | 12/28/1984 |
| Forwest Inc. | Subsidary | 12/31/1980 | 12/28/1984 |