Since 1865, there have been 44 earthquakes within a 100 kilometer (62 mile) radius from the center of Crater Lake. The highest magnitude of any quake occurring within the 100 km circle during this period was 4.3 on the Richter Scale. This reading was obtained on three occasions over the past 125 years: period: in 1920 (38km from the lake), in 1931 (77km), and in 1948 (55km). There are no magnitude records for 15 quakes occurring within the circle. They include the closest one, a quake that took place in October 1947, just eleven kilometers from Crater Lake.

Crater Lake does not appear to be the center of any significant seismic activity over the past century. Not only were the magnitude readings of lesser intensity, but there were only three quakes during the period that had their epicenters closer than 20km from the center of the lake. The next five closest quakes ranged from 35 to 39 kilometers; other quakes were 45km or further from Crater Lake. Average distance of the earthquakes from the lake was 55 km.

One chart shows their spatial distribution, with the center of Crater Lake being 42.57 north latitude and 122.07 west longitude. The other charts delineate epicenter distance from the park and quake magnitude.

Distance from lake	No. Quakes
less than 10 km	0
>=10 km < 20 km	2
>=20 km < 30 km	1
>=30 km < 40 km	5
>=40 km < 50 km	9
>=50 km < 60 km	7
>=60 km < 70 km	6
>=70 km < 80 km	8
>=80 km < 90 km	3
>=90 km	3
Magnitude	No. Quakes
no records	15
less than 1.0	0
>= 1.0 < 2.0	4
>= 2.0 < 3.0	14
>= 3.0 < 4.0	9
>= 4.0	3