40Ar-39Ar step-heating dating was applied to a basalt from Hole 462 and to basalt and dolerite samples from Hole 462A. Only a basalt sample at Hole 462A yielded a reasonable isochron age, 110 ± 3 million years. The radiometric age is consistent with the fossil record (Cenomanian) in the sediments, into which the basalt sill intruded. However, the age is much less than that of the oceanic basement as deduced from the magnetic anomaly (M-26).

Supplement to: Ozima, Minoru; Saito, K; Takigami, Yutaka (1981): 40Ar–39Ar geochronological studies on rocks drilled at Holes 462 and 462A, Deep Sea Drilling Project Leg 61. In: Larson, RL; Schlanger, SO; et al. (eds.), Initial Reports of the Deep Sea Drilling Project (U.S. Govt. Printing Office), 61, 701-703