The above-noted developments in the 1950s and 1960s in Moine geology show the growing recognition of the importance of combining lithological mapping with shrewd and careful observations in the field of folds, lineations and schistosities in order to unravel the geometrical history of deformed rocks. The increase in the field data collected, dips and strikes of bedding, cleavage or schistosity and the axial planes of folds, plunge amounts and geographical directions of folds and lineations (Fig. 11.1) led to an explosion of data and the neéd to be able to manipulate, display and synthesize such data at a time before computers were generally available (Howarth 1999). The process was enormously facilitated by the gradual extension of the use of the stereographic projection from crystallography (in which, as has been seen, upper hemisphere plotting is used), to structural geology (in which lower hemisphere plotting is conventional, presumably because folds and lineations are normally considered in their down-plunge attitudes, not the reverse).
There is no doubt that the widespread use of the stereogram in structural geology in Britain was promoted, more than any other factor (Sutton 1960b), by the publication of Phillips’ (1954b) textbook The Use of Stereographic Projection in Structural Geology, following his return from Australia. In the preface, Phillips paid tribute to the usefulness of Cotton & Garretty's (1945) report.268 Phillips’ chapter entitled ‘Tectonic synthesis in stereographic (and related) projection’, illustrated how the Lambert equal-area projection (Fig. 4.4) could be applied to summarize the orientation of joints, lineation and planes of schistosity, using examples from the schists of Start Point, Devon (Fig. 11.2) and the Moine schists.
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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.