Porth Seal (St. Martin's)
Also within
Condition (Natural England)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| SV919165 | — | Favourable | 0.99 | 2022-11-15 |
| SV924165 | — | Favourable | 0.99 | 2022-11-15 |
| SV925164 | — | Favourable | 0.99 | 2022-11-15 |
Climate exposure
This is about exposure to a nationwide pressure this habitat type carries — not a verdict on this site's own management.
Coastal habitats are exposed to sea-level rise and storm erosion. Where hard sea defences sit behind them, there's nowhere landward to retreat to — a squeeze that keeps compressing the habitat no matter how well it's managed.
Geology & landscape
Geological Feature: Raised Beach · Geological Period: Quaternary
Landscape processes: Coastal, Periglacial
Description
Description Porth Seal is important for Quaternary studies. It shows a sequence of deposits comprising1. Raised beach 2. A series of interbedded organic and inorganic silts and sands 3. Head. The organic deposits have provided Late Devensian radio-carbon dates and pollen from them indicates arctic tundra environmental conditions. The raised beach deposits appear in two layers, separated by a layer of head. They have been variously interpreted as two separate beaches, or as one beach partly reworked by solifluction. Porth Seal therefore provides important information on Late Pleistocene environmental conditions in S W England and demonstrates the stratigraphy and facies variations of the raised beach deposits.