The ground under College Outpost, United States — measured by the Global Seismographic Network (IRIS/USGS) station IU COLA 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 |
|---|---|---|---|
| M5.6 | 43 km NNW of Lake Minchumina, Alaska | 1970-01-01 00:00 UTC | 245 km |
| M5.5 | 92 km NNW of Aleneva, Alaska | 1970-01-01 00:00 UTC | 739 km |
| M5.0 | 81 km S of Sand Point, Alaska | 1970-01-01 00:00 UTC | 1,333 km |
| M4.2 | 1970-01-01 00:00 UTC | 665 km | |
| M4.2 | 1970-01-01 00:00 UTC | 638 km | |
| M4.2 | 1970-01-01 00:00 UTC | 1,315 km | |
| M3.9 | 1970-01-01 00:00 UTC | 1,366 km | |
| M3.9 | 1970-01-01 00:00 UTC | 1,491 km | |
| M3.8 | 1970-01-01 00:00 UTC | 260 km | |
| M3.8 | 1970-01-01 00:00 UTC | 611 km |
| Mag | Where | When | Distance |
|---|---|---|---|
| M7.7 | 12 km WSW of Pitaloza Arriba, Panama | 1970-01-01 00:00 UTC | 8,177 km |
| M7.0 | 191 km ENE of Nagqu, China | 1970-01-01 00:00 UTC | 7,969 km |
| M6.9 | 76 km NE of Ozernovskiy, Russia | 1970-01-01 00:00 UTC | 3,365 km |
| M6.9 | 197 km WNW of Port-Olry, Vanuatu | 1970-01-01 00:00 UTC | 9,605 km |
| M6.8 | central Mid-Atlantic Ridge | 1970-01-01 00:00 UTC | 11,752 km |
| M6.7 | central Mid-Atlantic Ridge | 1970-01-01 00:00 UTC | 11,675 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.