Image

Member's Price: £5

Non-Member's Price: £7

31. West Cornwall (2005) 2nd Edition


by A. Hall

West Cornwall is a classic area of British geology on account of its wide variety of igneous and metamorphic rocks, and its mineral deposits, especially tin and copper. The five itineraries cover all the prime localities in the region where these rocks can be examined including Land’s End, Marazion, St. Michael’s Mount, Cligga Head, Kynance Cove and The Lizard.

Look inside:

Table of Contents

Overview of Itineraries


Table of Contents


LIST OF FIGURES

INTRODUCTION

ITINERARIES

I Land’s End Peninsula
II Mount’s Bay
III St. Agnes District
IV Falmouth Bay
V The Lizard Peninsula

REFERENCES


Itineraries
Buy the guide to explore further...


West Cornwall is a classic area of British geology on account of its wide variety of igneous and metamorphic rocks, and its mineral deposits, especially tin and copper. The five itineraries cover all the prime localities in the region where these rocks can be examined including Land’s End, Marazion, St. Michael’s Mount, Cligga Head, Kynance Cove and The Lizard.

Itinerary I Land's End Peninsula
The Land's End Peninsula corresponds roughly with the outcrop of the Land's End granite intrusion, and the granite does not extend far beyond the present coastline. Patches of the metamorphic aureole are preserved at many places along the north and west coasts, at Longships Lighthouse at Land's End, and at Tater-du on the south coast of the peninsula. The hardening of the country rocks by contact metamorphism has evidently made them more resistant to erosion than the unaltered sediments away from the granite.
Start Point Lands End SW 3418 2534

Itinerary II Mount's Bay
The coast between the Land's End and Lizard peninsulas offers a complete section through the Tregonning-Godolphin granite and exposures of several smaller igneous intrusions. The itinerary begins at Marazion and ends at Porthleven.
Start Point Marazion SW 524 305

Itinerary III St. Agnes District
The St. Agnes District has been an important mining area in the past. It includes two small granite bosses, those of Cligga Head and St. Agnes Beacon, and their metamorphic aureoles. The mineralisation is concentrated around the two intrusions, which are therefore regarded as 'emanative centres'. The area is also notable for the only outcrop of Miocene sedimentary rocks in Britain.
Start Point Cligga Head, Perranporth SW 737 536

Itinerary IV Falmouth Bay
The coast around Falmouth is a convenient area in which to examine the Devonian sedimentary rocks in an unmetamorphosed condition. Within the Gramscatho Group, a distinction can be made between the Falmouth Beds, in which light brown sandstone predominates, and the Portscatho Beds, which are mainly grey slates. This stretch of coastline also shows two very interesting minor igneous intrusions. The estuary of the River Fal is a classic example of a drowned valley resulting from a rise in sea-level or subsidence of the land.
Start Point Pendennis Point, Falmouth SW 826 316

Itinerary V The Lizard Peninsula
The Lizard Peninsula is famous for the variety of igneous and metamorphic rock types which occur there, including the serpentinite which is the best example of its kind in England. Inland, the peninsula consists of a flat platform about 80 m above sea-level and there are relatively few exposures, but around the coast there are excellent sections of all the principal rock types.
Start Point Jangye-ryn SW 658 207

Map of Itineraries