Earth sciences belong to those scientific disciphnes which have to rely on high-performance computing not only because of the complexity of the prob-lems this discipline has to cope with but also for other reasons. Since the geometric structures are in general three-dimensional, the storage capacities required are large, and because of the large amount of data to be processed, high computing speeds are also required. For the second time the transac-tions contain two articles on this subject in this chapter. They clearly confirm that application of high-performance computing in analyses of the earth sci-ences is an absolute must. Needless to say, that the articles reported here are concerned with key problems of the subject.