Geology of Jersey
geological description of the Jersey Island, France
The geology of Jersey is characterised by the Late Proterozoic Brioverian volcanics, the Cadomian Orogeny, and only small signs of later deposits from the Cambrian and Quaternary periods. The kind of rocks go from conglomerate to shale, volcanic, intrusive and plutonic igneous rocks of many compositions, and metamorphic rocks as well, thus including most major types.
Brioverian sediments
The Brioverian rocks were formed between 900 and 700 mya. They were named after Briovère, the native name for St. Lô, in Normandy, which is the first area these rocks were described from. They start with turbidites in the west, centre and south of Jersey, including at St Ouens Bay, and St Aubin's Bay. The Brioverian sedimentary rocks are all well bedded and were originally the mid and outer parts of a submarine fan. This constitutes the Jersey Shale Formation. The shale is found at Gorey Harbour in the east coast, and La Belle Hougue Point, and Le Mont Mado granite has an occurrence. The shale is more easily eroded, and this has affected the shape of the island by the concave St Ouens's Bay and St Aubin's Bay.
This brief starts where responsible research should: with the source description of “Geology of Jersey” as geological description of the Jersey Island, France. Everything that follows is an evidence route, not borrowed authority.
Why this record matters
The subject matters to the places & architecture register because the source frames it as geological description of the Jersey Island, France. Its deeper value depends on whether names, dates, institutions and citations support that framing.
Maps, plans, fabric surveys and administrative records can establish how the site’s name, extent and function changed over time. The source revision retrieved here is dated Aug 22, 2026. The linked authority identifier is Q5535372. None of the 0 selected statements returned an explicit reference.
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This entry incorporates text from “Geology of Jersey” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.