The jump file contains two columns, time of jump (Myr) and distance of jump (km). To use the jump file filename when running Magellan the -j option can be used followed by the jump file (magellan -j filename). Equivalently the jump file can be specified in the configuration file, with the key jump=filename. Negative and positive jumps represent ridge jumps where the new ridge forms left and right of the failing ridge, respectively.
Here is an example of a jump file
% Everything written after the percentage sign is a comment
% This is a plain text file with the format below
% time(Myr) distance(km)
3 4.3
23 -3.1
2010-08-03
