From: Investigation on relationship between epicentral distance and growth curve of initial P-wave propagating in local heterogeneous media for earthquake early warning system
a value
γ value
150Â m
−6.71 × 10−1
200Â m
−4.42 × 10−1
600Â m
−2.94 × 10−1
1000Â m
−2.23 × 10−1