| Members | Lithological Description |
| Upper Shale | Greenish black shale encompassing a sandstone-siltstone. |
| Upper Sandstone | Mainly sandstone with subordinate siltstone. |
| Middle Shale | Black to greenish black, hard shale enclosing infrequent sandstone streaks. |
| Lower Sandstone | Predominant sandstone with minor shale and silt. |
| Lower Shale | Fissile shale with two discrete sandstone zones and negligible siltstone. |