Ham Ness
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Condition (NatureScot)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| F1 | Ordovician Igneous | Favourable | — | 2015-06-25 |
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: Rock Outcrop · Geological Period: Cambrian · Rock Type: Gabbro
Landscape processes: Coastal, Volcanic / Igneous
Description
HAM NESS Ham Ness is a small headland in the south-east corner of the island of Unst. The rocks exposed here are part of the Shetland ophiolite -a sequence of basic and ultrabasic igneous rocks formed at the end of the Cambrian period around 500 million years ago, and believed to represent a slice of ocean crust. The rocks were obducted into their present position as nappe structures. At Ham Ness, rocks representative of the higher levels of the ophiolite outcrop as a series of gabbros and microgabbros cut by a swarm of metabasite dykes. In places the swarm amounts to 50% of the outcrop and is interpreted as part of a sheeted dyke complex. The history of dyke injection was complex with several generations of dykes, some of which were intruded while the gabbro was still hot and plastic, others injecting through consolidated gabbro.