Sea mounts can be aged using naturally occurring isotopes of the element Argon. By obtaining Argon dates for selected sites along the New England sea mount chain, we can estimate the rate of motion of the tectonic plate over the hot spot. For the New England sea mount chain, we calcuated a rate of 4.7 cm per year. We have not determined ages for Kelvin and Manning sea mounts, but they can be estimated from this graph as 100 and 95 million years, respectively. Figure modified from Duncan 1984. J. Geophys. Res. 89 (B12):9980-9990.