The ground under Adak, United States — measured by the Global Seismographic Network (IRIS/USGS) station IU ADK 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 |
|---|---|---|---|
| M5.0 | 81 km S of Sand Point, Alaska | 1970-01-01 00:00 UTC | 1,127 km |
| M4.8 | 197 km S of Ust’-Kamchatsk Staryy, Russia | 1970-01-01 00:00 UTC | 1,411 km |
| M4.7 | 114 km SSW of Nikolski, Alaska | 1970-01-01 00:00 UTC | 487 km |
| M4.6 | 193 km SE of Attu Station, Alaska | 1970-01-01 00:00 UTC | 584 km |
| M4.6 | 100 km NNW of Nikolski, Alaska | 1970-01-01 00:00 UTC | 532 km |
| M4.6 | 82 km SSE of Akutan, Alaska | 1970-01-01 00:00 UTC | 796 km |
| M4.6 | 153 km WNW of Adak, Alaska | 1970-01-01 00:00 UTC | 149 km |
| M4.6 | 81 km SSE of Akutan, Alaska | 1970-01-01 00:00 UTC | 799 km |
| M4.5 | 166 km SE of Atlasovo, Russia | 1970-01-01 00:00 UTC | 1,478 km |
| M4.5 | 158 km S of False Pass, Alaska | 1970-01-01 00:00 UTC | 907 km |
| Mag | Where | When | Distance |
|---|---|---|---|
| M7.7 | 12 km WSW of Pitaloza Arriba, Panama | 1970-01-01 00:00 UTC | 9,747 km |
| M7.0 | 191 km ENE of Nagqu, China | 1970-01-01 00:00 UTC | 7,207 km |
| M6.9 | 76 km NE of Ozernovskiy, Russia | 1970-01-01 00:00 UTC | 1,776 km |
| M6.9 | 197 km WNW of Port-Olry, Vanuatu | 1970-01-01 00:00 UTC | 7,530 km |
| M6.8 | central Mid-Atlantic Ridge | 1970-01-01 00:00 UTC | 13,910 km |
| M6.7 | central Mid-Atlantic Ridge | 1970-01-01 00:00 UTC | 13,834 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.