Exactly what first attracted Phillips’ attention to the new science (Sander 1930) which became known as petrofabrics97 (Sander 1934) or structural petrology98 in the English-language literature is not known, but Phillips’ interest in this topic probably began during the course of his ‘Green Bed’ study. Petrofabrics is concerned with measuring the three-dimensional geographical orientation of mineral grains in rocks, primarily in order to deduce the directions of the tectonic forces responsible for making any preferred orientations detected.
It had long been appreciated, from field and laboratory studies on rocks (and also from metallurgical studies), that rocks deform under tectonic forces by recrystallization of existing minerals, chemical reactions producing new minerals, and by rotation of the mineral grains. In combination, these three processes construct in the rock a new texture or fabric, which reflects the tectonism that produced it. In order to determine the spatial orientation of this fabric correctly, it is therefore necessary to collect rock samples which are carefully orientated geographically. This is achieved in each case by making suitable marks on the surface of the rocks, defining the geographical and spatial orientation of each specimen, before it is removed from the outcrop.99 This enables the orientation in the field to be precisely transferred right through to the final thin-section of the rock.
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The Life of Frank Coles Phillips (1902–1982) and the Structural Geology of the Moine Petrofabric Controversy
Frank Coles Phillips was a photographer mineralogists and structural petrologists working in themiddle of the twentieth century. He was very influential, both in the UK and abroad and was responsible for encouraging the development of structural geology as a discipline in Australia and for the adoption of the stereogram as a fundamental interpretational tool in structural geology in the UK. He was a superb teacher, perhaps best known amongst mineralogist and geologist of today for his classic textbooks, An Introduction to Crystallography and The Use Steographic Projection in Structural Geology.
Phillips was the first to apply the methods of structural petrology (the study of the microscopic fabric of deformed rocks) in an attempt to unravel the complex structural history of the Moine rocks of northwestern Scotland. his findings were at odds with those of his contemporaries and resulted in the Moine petrofabrics becoming embroiled in a long-running controversy, only completely resolved since the mid-1980s.
This geological biography of an important twentieth century mineralogist and petrolohist takes a critical look at Philips' research in the context of contemporaneous developments in structural and Moine geology. It reviews his work in relation to both past problems and present solutions. It will be of interest to all gelogist, especially structural and microstructural geologist, historians of science and the general leader with an interest in science.