Green Geology

Useful links:

 

South West Coast Path

 

How to get there:

Bus

 

Nearest railway station:

Roche (11 miles)

 

Accessibility:

Steps, a stile, long-ish walk along coastal path.

Devonian

 

Site of Special Scientific Interest (SSSI)

Pentire Peninsula, Cornwall

 

Page updated March 2013

The Pentire Peninsula, north of Wadebridge in an Area of Outstanding Natural Beauty and part of a Heritage Coast in North Cornwall, has slate in spades and has wonderfully clear pillow lavas.  It is designated as a Site of Special Scientific Interest (SSSI) and is owned by the National Trust.  

 

Outcrops here provide exposures of one of the most important geological structures in south-western England. The Padstow Confrontation in the Upper Devonian slates is probably unique in Britain.  Interpretation of the Padstow Confrontation remains highly contentious.  During the Variscan Orogeny, folds to the north of Polzeath were formed with a southwards inclination; to the south, however, very similar folds are inclined in the opposite, northward direction, creating a 'facing confrontation'.  It is likely that these two structures were formed at opposite sides of a now-closed ocean.

 

As you walk northwards onto the peninsula from the village of New Polzeath, there is an outcrop showing excellent examples of both folding and cleavage at Pentireglaze Haven.

 

Sedimentologists will be interested to know that just north of here the Pentire Peninsula has the type section for the Gravel Cavern Conglomerate, a mud flow conglomerate with interesting fossils.

 

There are excellent pillow lavas - basalt which erupted underwater – here which represent a major episode in the Upper Devonian and there are greenstone bodies (slightly-altered basalts) which were probably intruded close to the surface of the Earth.

 

This is where some of the most poignant lines in the English language were written: Laurence Binyon wrote his poem “For the Fallen” on the cliffs here at the headland to the north of Hayle Bay.

 

The Pentire Peninsula is just to the north of Hayle Bay which separates Polzeath and Trebetherick so Trebetherick Point can be visited as part of the same walk.

Click to enlarge

PP from Stepper Point