The Lewisian: Britain's Oldest Rocks Graham Park
The first 2,500 million years of the geological history of Britain are stored in the gneisses of the Lewisian Complex of North West Scotland. This book explores the long journey of discovery in which…
Specifikacia The Lewisian: Britain's Oldest Rocks Graham Park
The first 2,500 million years of the geological history of Britain are stored in the gneisses of the Lewisian Complex of North West Scotland. This book explores the long journey of discovery in which this history has been gradually deciphered since the end of the 19th Century when these rocks were first investigated in detail. The usual tools of stratigraphic investigation were of no value in dealing with such a complex assemblage of highly deformed and metamorphosed rocks; there was no fossil evidence and few signs of recognisable sedimentary strata. This book charts the increasing sophistication of the geochronological and geochemical techniques used to decipher the complex. The first important breakthrough was the recognition that a set of intrusive metamorphosed dykes could be used, perhaps, to separate episodes of deformation and metamorphism that occurred before the dykes were