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M6.9 earthquake, Alaska, 1999-03-20

MagnitudeM6.9mwc

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Depth33 km

Time (UTC)1999-03-20 10:47

Rank in 199920 / 135among M6+

Rank since 19001933 / 14,458

Energy vs an M6×22approx.

78 km WSW of Adak, Alaska · 51.59, -177.67

M6.5+ within 300 km (largest first)

1957 M8.6M8.6

1986 M8.0M8.0

1996 M7.9M7.9

1905 M7.6M7.6

1929 M7.3M7.3

1996 M7.3M7.3

2007 M7.2M7.2

1905 M7.2M7.2

1957 M7.2M7.2

1957 M7.1M7.1

1970 M7.1M7.1

Earlier M6+ within 300 km

Event	Time (UTC)	Depth	Place
M6.4 1997-10-15	1997-10-15 03:11	22 km	99 km WSW of Adak, Alaska
M6.4 1997-06-17	1997-06-17 21:03	33 km	195 km WSW of Adak, Alaska
M6.0 1996-08-19	1996-08-19 04:19	33 km	Andreanof Islands, Aleutian Islands, Alaska
M7.3 1996-06-10	1996-06-10 15:24	26 km	46 km SSW of Adak, Alaska
M7.9 1996-06-10	1996-06-10 04:03	33 km	77 km WSW of Adak, Alaska
M6.5 1996-06-08	1996-06-08 23:19	33 km	111 km WSW of Adak, Alaska
M6.2 1994-04-05	1994-04-05 09:35	20 km	123 km WSW of Adak, Alaska
M6.0 1993-11-11	1993-11-11 00:28	19 km	194 km SSW of Adak, Alaska
M6.9 1993-05-15	1993-05-15 21:52	32 km	151 km WSW of Adak, Alaska
M6.2 1992-11-11	1992-11-11 21:26	33 km	195 km WSW of Adak, Alaska

Energy ratio uses the rule that one magnitude unit is about 32 times the energy. Magnitudes and locations are USGS values and can differ from national agencies. Older records are less complete and less precise.