1. A method, comprising: receiving an input dataset that corresponds at least in part to a subsurface three-dimensional geologic formation, wherein: the input dataset is a simultaneous-source acquired dataset that includes a plurality of shots, and one or more shots in the plurality of shots includes data corresponding to a plurality of source activations; separating the input dataset into a plurality of separated shots, wherein respective shots in the plurality of separated shots correspond to respective shots in the plurality of shots in the input dataset; for one or more separated shots in the plurality of separated shots: interpolating respective separated shots to form respective interpolated shots, and encoding the respective interpolated shots to form respective simulated simultaneous shots; forming a hybrid simultaneous-source dataset based at least in part on the simulated simultaneous shots and the input dataset; and separating the hybrid simultaneous-source dataset into a second plurality of separated shots, wherein respective shots in the second plurality of separated shots correspond to respective shots in the hybrid simultaneous-source dataset.