White Island (Isles of Scilly)
| White Island | ||
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| Waters | Celtic sea | |
| Archipelago | Isles of Scilly | |
| Geographical location | 49 ° 58 '45 " N , 6 ° 17' 32" W | |
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| surface | 15 ha | |
| Highest elevation | 21 m | |
| Residents | uninhabited | |
White Island is an uninhabited island in the Isles of Scilly . It is the northernmost of the Scillys and can be reached on foot at low tide via a raffle from St. Martin’s .
history
A Bronze Age stone grave ( Entrance Grave ) is located at the highest point of the only 0.15 km² large island, which is 21 m above sea level. In addition, there are also other prehistoric sites, such as B. several Cairns , including a Chambered Cairn . Further south, under the protection of the hill, there are six smaller mounds or cairns. Two preserved walls with associated trenches should belong to former fenced-in fields. An examination of one of the cairns revealed that it was about ten feet wide and probably enclosed by a double wall on its north side. It was not big enough for a hut foundation (Hut Circle). Only part of the island has so far been listed as an ancient monument , but this is to be extended to the entire island.
geology
White Island consists of the same coarse-grained, richly porphyry granite of the Isles of Scilly Pluton as the northern part of St. Martin's (facies G 1a ). The same granite appears at the northeast tip, but in addition in a non-porphyry formation. This special facies underlay the richly porphyry granite with horizontal but wavy contact. Trained especially narrow joint sets run parallel to the contact, but lost in the overlapping Hauptfazies.
In the south of the island two fine-grained granite passages cross , one of them is 1.5 meters wide and strikes northeast-southwest. The latter has rounded but also irregular inclusions of the host granite. This suggests that the coarse-grained, richly porphyry granite was not yet fully solidified when the dike penetrated. The other corridor is roughly northwest-southeast, its contact relationships are sharp and it should therefore be younger.
Fragments of the metamorphic host rocks - the so-called killas - were found at the northeast tip . In the column of the Chad Grit , which almost divides the island, there are late Pleistocene sediments , which is why the island has also been designated a Site of Special Scientific Interest . Traces of the Quaternary are a raised surf platform, pebbles with solifluction structures and loess blown out of the Irish Sea, as well as two upcoming breccia deposits .
Flora and fauna
The island has also been named an SSSI because of its diverse flora and fauna. A large number of plants are native to the island, which is characterized by Entisol . Among other things, bracken , heather , blackberries , Crassulaceae , cochlearia officinalis , English stonecrop , trefoil , Festuca rubra , Erica cinerea , heath bedstraw , Plantago Coronopus , gorse , beach Thrift , Lonicera Periclymenum and wild turnip . In addition, several species of seagulls have been spotted on White Island . Among other things, black-backed gulls , herring gulls , herring gulls , kittiwakes and fulmars .
Web links
- Information about the nature of the island (English; PDF; 6 kB)
- White Island on www.megalithic.co (engl.)
Individual evidence
- ^ SJL Mullis, S. Salmon and T. Powell: Insights into the formation of the Isles of Scilly pluton . In: Geoscience in south-west England . tape 10 , 2001.