where A is in g, λ = 6.6 × 10-2, α = 0.40, β = -1.39 and σ = 1.99 (this is multiplication factor).
Use 113 records with distances between 15 to 350km from San Fernando earthquake to find distance
Use 27 records of Wiggins (1964) from El Centro and Ferndale areas, with magnitudes between 4.1 and
7.0 and distances between 17 and 94km (assuming focal depth of 15km), to compute magnitude dependent
terms assuming distance dependence is same as for San Fernando.