General Statement.—The general geologic relationships found in the crystalline rocks at Shawinigan Falls were set forth in an earlier paper.1 This paper presents the results of petrofabric analyses of some of the typical rocks from that area.
Most of the work on petrofabrics has been done by the Austrian workers, Sander and Schmidt,2 and their results have been published in German, but five articles in English make it possible for the English-speaking reader to gain some knowledge of the methods without recourse to the German literature.3 For that reason, the general statements will be made as brief as possible except where the present writers have deviated from the methods evolved by the continental workers.
Petrofabric analysis involves not only the measurement of attitude of joints, linear structures, flow planes, and bedding or foliation planes but also the statistical examination of oriented specimens. Thin sections are cut . . .