(Table 1) Potassium, argon and age at DSDP Holes 81-553 and 81-555, explatory

Lambda-beta = 4.962*10**-10 yr**-1; Lambda-3 = 0.581*10**-10 yr**-1; 40K = 1.167*10**-2 atom %; errors computed from {EK**2+(1+A/R)**2 E40**2 + E38**2 + (A/R)**2 E36**2}**1/2 where R = (100-A) = 40Ar*/40ArT with error in K, EK = 1.5% and errors in peak heights, E40 = E38 = 0.5%; E36 = 1%. The best age derivable from this data for samples A, C, and D is 59.0 ± 3.1 m.y.