Scale of Geotectonic Phenomena

The processes of geotectonics range through fifteen orders of magnitude of length and have an equal spread in time. Many behaviour thresholds exist and because the several physical properties involve different powers of length or time, terms which are quite insignificant on one scale may be the dominant ones in others. No one mental or mathematical model has validity over the whole field; hence models must be deliberately selected for the time-size field of thinking or calculation. Nomenclature should change with field so that it signifies the kind of behaviour relevant to the scale. The time field for impact crater phenomena makes Dietz's astrobleme interpretation of the Vredefort dome extremely improbable.