Spectral evolution of Ca II 854.2 nm, Ca II H, Mg II k, and Si IV 140.3 nm at the locations of interest. The x-axes are in units of Doppler offset, where negative (positive) velocities indicate blueshifts (redshifts). The intensity is shown in units of brightness temperature. The orange line profiles are taken at t′ = 0 s, where the highest (lowest) intensity of the profiles in each row corresponds to the maximum (minimum) intensity of the respective colourbars. We note that the intensity of Si IV 140.3 nm at the L1 location has a maximum of I_ν = 7 kK in order to visually enhance the features of the relatively weak emission. The orange line profiles give a better indication of the difference in intensity across the Si IV row.