The ground under Afiamalu, Samoa — measured by the Global Seismographic Network (IRIS/USGS) station IU AFI and redrawn here every 15 minutes. A thin band means a quiet ground; a tall spike is a passing earthquake, near or on the other side of the planet.
| Mag | Where | When | Distance |
|---|---|---|---|
| M5.9 | Fiji region | 1970-01-01 00:00 UTC | 1,081 km |
| M5.5 | 122 km W of Neiafu, Tonga | 1970-01-01 00:00 UTC | 644 km |
| M5.5 | 283 km E of Levuka, Fiji | 1970-01-01 00:00 UTC | 824 km |
| M5.4 | 76 km S of Pangai, Tonga | 1970-01-01 00:00 UTC | 776 km |
| M5.2 | 92 km NNE of Hihifo, Tonga | 1970-01-01 00:00 UTC | 223 km |
| M5.2 | 71 km ESE of ‘Ohonua, Tonga | 1970-01-01 00:00 UTC | 889 km |
| M5.1 | 236 km E of Levuka, Fiji | 1970-01-01 00:00 UTC | 846 km |
| M5.1 | 36 km E of Safotu, Samoa | 1970-01-01 00:00 UTC | 64 km |
| M5.0 | 67 km E of ‘Ohonua, Tonga | 1970-01-01 00:00 UTC | 864 km |
| M5.0 | south of the Fiji Islands | 1970-01-01 00:00 UTC | 1,466 km |
| Mag | Where | When | Distance |
|---|---|---|---|
| M7.7 | 12 km WSW of Pitaloza Arriba, Panama | 1970-01-01 00:00 UTC | 10,318 km |
| M7.0 | 191 km ENE of Nagqu, China | 1970-01-01 00:00 UTC | 11,239 km |
| M6.9 | 76 km NE of Ozernovskiy, Russia | 1970-01-01 00:00 UTC | 7,909 km |
| M6.9 | 197 km WNW of Port-Olry, Vanuatu | 1970-01-01 00:00 UTC | 2,445 km |
| M6.8 | central Mid-Atlantic Ridge | 1970-01-01 00:00 UTC | 16,580 km |
| M6.7 | central Mid-Atlantic Ridge | 1970-01-01 00:00 UTC | 16,568 km |
Waves from a large earthquake reach this station minutes later — up to about 20 minutes from the far side of the Earth. Look for a spike in the helicorder at that time.