Statistical Methods in Sedimentary Petrology: Part III. Cartograpic Methods

Abstract

The purpose of this paper is to discuss methods by which the data of sedimentary petrology (mineralogical composition, grainsizes, etc.) may be most usefully recorded upon a map. The ultimate aim which the writer had in mind when commencing this work was to learn something of the palaeogeography of North-East Yorkshire during Middle Jurassic times.¹ It soon became evident, however, that a map upon which the data have been registered may be a record not only of the conditions at the time of deposition but also of the subsequent mineralogical changes in the rocks themselves and, what was less expected, of the tectonic development of the region as a whole.