From: Rapid magnitude determination from peak amplitudes at local stations
T c (s)
a
b
c
1
1.23
3.48
3.02
2
3.21
3.17
5
2.61
4.10
10
1.99
5.31
20
1.46
6.39
50
1.22
6.80
100
1.24
6.64