CYNGOR CEFN GWLAD CYMRU

COUNTRYSIDE COUNCIL FOR WALES

SITE OF SPECIAL SCIENTIFIC INTEREST CITATION

VALE OF GLAMORGAN PENARTH COAST

Date of Notification: 1965, 1984

National Grid Reference: ST 189681

O.S. Maps: 1:50,000 Sheet number: 171

1:25,000 Sheet number: ST 16

Site area: 92.7 ha

Description:

This coastal section is regarded as the type locality for the Penarth Group, showing an extensive section from the Blue Anchor Formation to the Lower Lias. The exposures have been proposed as the type section for the Westbury Formation, Cotham and Langport Members and Lilstock Formation. This classic locality exposes a thirteen metre 'Rhaetic' section resting on a conspicuously waterworn surface beneath the 'Sully Beds'. The Westbury 'bone bed' development here yields the normal assemblage of fish and reptile debris. This coastal section is also the best available in the Blue Lias of South Wales and is of importance for its comparisons with the 'littoral' more marginal rocks of the Lias further west in Glamorgan. This through-section from the Keuper to the Lower Sinmurian is unrivalled in any other section in Wales and the site is consequently regarded as one of Britain's most important stratigraphical localities.

The site also includes some species rich calcareous grassland and cliff-top scrub which supports a number of plant species of limited occurrence and distribution in the former counties of Mid and South Glamorgan, including Dyer's Greenweed Genista tinctoria, Butterfly Orchid Plantanthera chlorantha, Bee Orchid Ophrys apifera and Adder's Tongue Ophioglossum vulgatum. Lavernock Point is a well known observation point for migratory birds.

Remarks:

The calcareous grassland area is a Nature Reserve managed by the Glamorgan Trust for Nature Conservation.