Table 1 Geographic coordinates and dip latitudes of the GPS receivers
| Station | Latitude | Longitude | Dip latitude |
|---|---|---|---|
| São Luís | 02.5°S | 44.3°W | 04.7°S |
| Imperatriz | 05.5°S | 47.4°W | 05.5°S |
| Petrolina | 09.4°S | 40.5°W | 13.5°S |
| Ilhéus | 14.8°S | 39.0°W | 19.1°S |
| Belo Horizonte | 19.8°S | 43.9°W | 19.9°S |
| São José dos Campos | 23.2°S | 45.9°W | 20.9°S |