Water Crag
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Condition (Natural England)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| SD152973 | — | Favourable | 3.59 | 2021-11-10 |
Geology & landscape
Geological Period: Ordovician · Rock Type: Granite
Landscape processes: Volcanic / Igneous
Description
Description Water Crag is an area of crag covered fell side to the north of Devoke Water, in south west Cumbria. Important exposures of slates and volcanic rocks of Ordovician age, Eskdale Granite and greisen are all present at the site. Here the Eskdale Granite is in contact with rocks of Ordovician Borrowdale Volcanic Group, although locally a narrow belt of slates tentatively assigned to the Skiddaw Group intervenes between these two rock types. On the southern flank of the crag a large area of coarse grained quartz topaz rock forms agreisen along the contact. Exposures of the greisen on clear ice smoothed surfaces is spectacular. Locally within the greisen small streaks and pockets of sulphides, up to one centimetre across, have yielded traces of bismuth and molybdenum minerals. Immediately adjacent to the contact with the slates a 0.5 metres band of quartz andalusite rock is present as a modification of the granite. The site is significant for the magnificent display it provides of greisenisation along the contact of a major granitic intrusion together with the presence of the remarkable quartz andalusite rock.