Kirschvink and his colleagues (Kirschvink et al. 1986; Kirschvink, 1990) extended Klinowska’s work. They mapped stranding positions from a computerized data set onto digital aeromagnetic data for the east coast of the United States and then developed procedures that demonstrated statistically reliable associations of stranding sites with locations where magnetic minima intersected the coast. (nT; 0.1 % of the total field) were sufficient to influence stranding location (Kirschvink et al. 1986; Kirschvink, 1990).