Outcrops, isotopic ages, terranes and the undesirable fate of tectonic interpretations

Abstract

This paper embodies a criticism of the recent proliferation of papers reporting high-quality isotopic ages combined with extremely poor tectonic interpretations resulting from an absence or non-consideration of high-quality geological mapping and ignorance of the basic tenets of tectonics, particularly of the comparative anatomy of mountain ranges. It appears that some geologists began to think that chronology (not even chronostratigraphy) alone is sufficient for understanding the geological history of a region. This seems a result of the mistaken belief that one kind of data can yield the clues to the entire geological history of an area. The kind of data chosen has become a matter of the most recent fashion, a sort of ‘methodomania,’ not what is required by the geological nature of the region under investigation. The appreciation that geological data are woefully incomplete and inadequate in most cases (even where superb geological maps exist) to generate perfect reconstructions is being lost. This brings with it the grave danger of impoverishing our conceptual repertoire of geological structures and evolutionary paths of tectonic entities such as orogens, taphrogens and keirogens leading to poor interpretations bereft of any sound geological basis.