| Stage | Exposed area (Km2) | True area (Km2) |
| 1 | 4204.194 | 10842.858 |
| 2 | 2661.766 | 6638.664 |
| 3 | 2257.373 | 3976.898 |
| 4 | 1719.525 | 1719.525 |
| Total area | 10842.858 | ----------- |