Atlas of deformational and metamorphic rock fabrics / Атлас деформационно-метаморфических структур горных пород

Our knowledge of metamorphic and deformational rock fabrics has been acquired largely by studying the products of deformation in ancient fold belts. As such, our understanding of how rock fabrics form has been built up from inferences about, rather than direct observations of, processes that might have operated, and many of those inferences have proved incorrect. Extension of the deep-sea drilling project to actively deforming continental margins is a step towards providing information about rock fabrics that are currently forming, as is the attempt to measure stress, strain and nature of pore fluid in modem fold belts, but these approaches are very much in their infancy. Similarly, direct observations of fabric changes have begun using analogue materials. The problem arising from such an inferential study is that we have no prior knowledge of the natural categories or divisions that exist. The major categories of rock fabric have, by necessity, been established arbitrarily in the hope that they provide a useful subdivision. As novel observations or techniques open new vistas, earlier ideas have had to be modified or discarded. <...>