1997-98 Lull

After executing queries for Richter 3+ Quakes from 1970-1998, and again for Richter 5+ Quakes 1970-1998 we can see an exponential increase in earthquakes in general and a relatively stable incidence of Richter 5+ earthquakes. I conclude that earthquakes are on the increase, however, all of this increase to 1998 falls to weaker earthquakes (below Richter 5). Both graphs also show an interesting significant decrease in earthquakes in 1999. While this may indicate a "cooling down", there's another interpretation. If you look at the Richter 3+ graph more closely, you will see that after every increase there was a decrease followed by a stronger increase. If we assume this pattern to continue, we may expect that we're currently in a "silence before a storm" and that the earthquakes will drastically increase later, probably including an increase in higher Richter earthquakes.

Richter 3+ Quakes 1970-7/1998	Richter 5+ Quakes 1970-7/1998
1970 3504 1971 3980 1972 3670 1973 4010 1974 3991 1975 4821 1976 4805 1977 4121 1978 4408 1979 5223 1980 6295 1981 5113 1982 5344 1983 6431 1984 5998 1985 6834 1986 7310 1987 6496 1988 6315 1989 6907 1990 7553 1991 7636 1992 10884 1993 9400 1994 9830 1995 12495 1996 13112 1997 11273 7/1998 10300	1970 1097 1971 1198 1972 1167 1973 1174 1974 1174 1975 1281 1976 1447 1977 1451 1978 1272 1979 1130 1980 1130 1981 953 1982 1173 1983 1460 1984 1256 1985 1410 1986 1393 1987 1188 1988 1181 1989 1189 1990 1382 1991 1214 1992 1316 1993 1262 1994 1333 1995 1211 1996 1164 1997 940 7/1998 708

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