| Terrain elevations (m) | Areas (% of total) | ||
| Alluvial deposits | Marine sediments | Barreiras group | |
| 0 to 5 | 70.9 | 70.3 | 0.8 |
| 5.1 to 10 | 25.6 | 29.7 | 5.1 |
| 10.1 to 15 | 3.5 | 0 | 11.9 |
| 15.1 to 30 | 0 | 0 | 14.5 |
| 30.1 to 50 | 0 | 0 | 60.3 |
| 50.1 to 72 | 0 | 0 | 7.4 |