1. A method for producing a training data set from a set of multidimensional geophysical input data samples for training a model to predict target data, comprising: dividing a set of geophysical input data samples into a plurality of first subsets of input data samples, dividing each of the first subsets into a plurality of first clusters, generating a first set of prototypes each representing one of the first clusters, and dividing the first set of prototypes into a plurality of second clusters.