Jersey. Description of 1:25 000 Channel Islands map Sheet 2

The Channel Islands are situated in the Gulf of St Malo and geologically have much in common with the adjacent French mainland of Normandy and Brittany. Their importance to British geologists lies principally in the magnificent coastal sections that expose rocks which have been virtually unaffected by either Caledonian or Hercynian metamorphism, and which, therefore, preserve a largely intact record of local Precambrian and Palaeozoic events. In addition, because the islands lay to the south of the Pleistocene ice-sheets, the superficial deposits present interesting comparisons and contrasts with those of both Britain and France.

This book describes the geology of Jersey. The oldest rocks in the Channel Islands are confined to the Bailiwick of Guernsey, comprising the islands of Guernsey, Sark, Brecqhou, Herm, Jethou, Alderney, Burhou and the Casquets. Metamorphic rocks–principally schists and gneisses–form the southern part of Guernsey, most of Sark and Brecqhou, and the western part of Alderney. Their structures show that they have undergone several phases of deformation and metamorphism during early Proterozoic time at about 2020 million years (Ma) ago.

Author Bishop, A.C.

ISBN 011884458X

Year Published 1989