Collins. Poroelastic.
N J C
25 25 1 0
3
  0    0     0     0   0   0   0
  0 1500     0     0   0   1   0 
200 -1 -1 0 0 0 0 0              # Cp<0 Cs<0 flag poro-elastic layer
1 2.25E9 6.6298339E-10 2.0 2.4918804E+10 .3 1.0E-10 
-1.E-5 2.016E+9 1.582740E+9 1.454770 0.4259962 1.0

25
0. 250 51 25
600 1E8
-1 1 950
0 10 20 2
0 250 10 50
30 90 3